zotero-db/storage/EVVPVDIG/.zotero-ft-cache

MCWP 3-16.3 FM 6-50
TTP for the Field Artillery Cannon Gunnery

U.S. Marine Corps

PCN 143 000004 00

FOREWORD

This publication may be used by the US Army and US Marine Corps forces during training, exercises, and contingency operations.

General, USA Commanding Training and Doctrine Command

Lieutenant General, USMC Commanding General Marine Corps Combat Development Command

FM 6-50, MCWP 3-1.6.23
PREFACE This publication is designed primarily for the cannon battery. It is a how-to-train manual intended to provide general guidance to the commander and his principal subordinates. It is designed for battery leaders and should be used in conjunction with equipment technical manuals, Marine Corps combat readiness evaluation system (MCCRES), Marine Corps individual training standards (ITS), Army training and evaluation program (ARTEP) mission training plans (AMTPs), soldier manuals, and trainer’s guides. This publication sets forth suggested duties and responsibilities of key personnel and addresses doctrine and procedures for cannon battery operations and training, It is based on current tables of organization and equipment (TOE) and provides a starting point from which each commander can adjust his battery operations and training based on his modification tables of organization and equipment (MTOE); actual personnel and equipment till; local training scenario; and mission, enemy, terrain, troops, and time available (METT-T). This publication presents standardized procedures relevant to cannon battery operations (Appendix A). These procedures are denoted in text by an asterisk (*). This publication implements the following North Atlantic Treaty Organization (NATO) standardization agreements (STANAGs) and quadripartite standardization agreements (QSTAGs):
STANAG 2934, Edition 1, Chapter 13, Artillery Procedures, and QSTAG 503, Edition 2, Bombing, Shelling, Rocketing, Mortaring and Location Reports. STANAG 2041, Edition 4 and QSTAG 520, Edition 1, Operation Orders, Tables and Graphs for Road Movement. STANAG 2047, Edition 6, and QSTAG 183, Edition 3, Emergency Alarms of Hazard or Attack (NBC and Air Attack Only). STANAG 2113, Edition 5, Denial of A Unit’s Military Equipment and Supplies to an Enemy. STANAG 2154, Edition 5 and QSTAG 539, Edition 1, Regulations for Military Motor Vehicle Movement by Road. As used throughout this publication, the words howitzer, gun, cannon, weapon, and piece are synonymous. The proponent of this publication is HQ TRADOC. Send comments and recommendations on DA Form 2028 (Recommended Changes to Publications and Blank Forms) directly to:
Commandant US Army Field Artillery School ATTN: ATSF-DD Fort Sill, Oklahoma 73503-5600 Unless this publication states otherwise, masculine nouns and pronouns do not refer exclusively to men.
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FM 6-50, MCWP 3-1.6.23
PREFACE This publication is designed primarily for the cannon battery. It is a how-to-train manual intended to provide general guidance to the commander and his principal subordinates. It is designed for battery leaders and should be used in conjunction with equipment technical manuals, Marine Corps combat readiness evaluation system (MCCRES), Marine Corps individual training standards (ITS), Army training and evaluation program (ARTEP) mission training plans (AMTPs), soldier manuals, and trainer’s guides. This publication sets forth suggested duties and responsibilities of key personnel and addresses doctrine and procedures for cannon battery operations and training, It is based on current tables of organization and equipment (TOE) and provides a starting point from which each commander can adjust his battery operations and training based on his modification tables of organization and equipment (MTOE); actual personnel and equipment till; local training scenario; and mission, enemy, terrain, troops, and time available (METT-T). This publication presents standardized procedures relevant to cannon battery operations (Appendix A). These procedures are denoted in text by an asterisk (*). This publication implements the following North Atlantic Treaty Organization (NATO) standardization agreements (STANAGs) and quadripartite standardization agreements (QSTAGs):
STANAG 2934, Edition 1, Chapter 13, Artillery Procedures, and QSTAG 503, Edition 2, Bombing, Shelling, Rocketing, Mortaring and Location Reports. STANAG 2041, Edition 4 and QSTAG 520, Edition 1, Operation Orders, Tables and Graphs for Road Movement. STANAG 2047, Edition 6, and QSTAG 183, Edition 3, Emergency Alarms of Hazard or Attack (NBC and Air Attack Only). STANAG 2113, Edition 5, Denial of A Unit’s Military Equipment and Supplies to an Enemy. STANAG 2154, Edition 5 and QSTAG 539, Edition 1, Regulations for Military Motor Vehicle Movement by Road. As used throughout this publication, the words howitzer, gun, cannon, weapon, and piece are synonymous. The proponent of this publication is HQ TRADOC. Send comments and recommendations on DA Form 2028 (Recommended Changes to Publications and Blank Forms) directly to:
Commandant US Army Field Artillery School ATTN: ATSF-DD Fort Sill, Oklahoma 73503-5600 Unless this publication states otherwise, masculine nouns and pronouns do not refer exclusively to men.
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FIELD MANUAL No. 6-50 MARINE CORPS WARFIGHTING PUBLICATION No. 3-1.6.23

*FM 6-50, MCWP 3-1.6.23
HEADQUARTERS DEPARTMENT OF THE ARMY UNITED STATES MARINE CORPS Washington, DC, 23 December 1996

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By Order of the Secretary of the Army:
Official: Administrative Assistant to the
Secretary of the Army
02743

FM 6-50/MCWP 3-1.6.23 23 DECEMBER 1996
DENNIS J. REIMER General, United States Army
Chief of Staff

BY DIRECTION OF THE COMMANDANT OF THE MARINE CORPS
PAUL K. VAN RIPER Lieutenant General, U.S. Marine Corps
Commanding General Marine Corps Combat Development Command
Quantico, Virginia

DISTRIBUTION: Active Army, Army National Guard, and U.S. Army Reserve: To be distributed in accordance with the initial distribution number 110776, requirements for FM 6-50.
C U.S. GOVERNMENT PRINTING OFFICE: 1996-527-027/60031

FM 6-50, MCWP 3-1.6.23

CHAPTER 1
MISSION, ORGANIZATION, AND KEY PERSONNEL

Section I
MISSION AND GENERAL ORGANIZATION

1-1. MISSION
a. The mission of the field artillery (FA) is to destroy, neutralize, or suppress the enemy by cannon, rocket, and missile fires and to help integrate all fire support assets into combined arms operations. b. The field artillery cannon battery is the basic firing element of the cannon battalion regardless of how the battery is organized. The battery’s capability is enhanced through the flexibility and survivability provided under an organization based on platoons. In no way should the references to platoon- or battery-based organizations be construed as the structure for operational employment. Rather, the terms pertain solely to organizational structure.
Note: For tactics, techniques, and procedures for the M109A6 (Paladin), see FM 6-50-60.
1-2. FIELD ARTILLERY ORGANIZATION
The field artillery is organized into light, medium, and heavy artillery on the basis of weapon caliber. a. Each light artillery (105-mm M102, M101A1, or M119A1) battery has a headquarters section and six howitzer sections. b. Each medium (155-mm M109A2-A6 and M198) battery is organized in one of two ways:
(1) A platoon-based unit has a headquarters and two firing platoons of three or four howitzer sections each. This organization allows for platoon operations.
Note: The M109A5 howitzer battery organic to the regimental armored cavalry squadron is designed to function independently and to perform most of its own support functions. It is organized, trained, and equipped to operate in direct support of the squadron.

(2) A battery-based unit has a headquarters section and six howitzer sections. c. Organization does affect employment. In a unit organized with a single six-gun battery, the battery is employed as a single unit under the direct control of the battery commander. In a platoon-based unit, the battery may be employed in one of the following ways:
As two platoons under the control of the battery commander (BC). As a single unit, with the platoons merged. As two separate platoons directly controlled by the battalion S3, through the BC, with the battery commander providing reconnaissance, selection, and occupation of position (RSOP) and logistical support. This last employment option is the least desirable. It is used only when the tactical situation permits no other means of command and control.
Note: AH battalions in the US Marine Corps are organized into three six-howitzer batteries.
1-3. COMMAND AND CONTROL OF BATTERIES
a. The FA cannon battalion issues movement instructions and other orders to the battery, regardless of whether the battery is battery- or platoon-based. Orders are issued to the battery commander or his operations center. These orders specify the artillery requirements of the tire support coordinator (FSCOORD) rather than trying to specify how the commander is to accomplish the mission. The BC selects platoon positions within the larger battery area selected by the S3. The battery commander will also determine which platoon is better able to move at any given time. The functions of the FA battalion tactical operations center (TOC) are to position and control the fires of the batteries. The BC positions and controls the tires of his platoons. The battalion TOC should be involved with directly controlling platoons only when no other option is available.

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FM 6-50, MCWP 3-1.6.23

b. In a battery-based (3x6) unit, command and control of the firing battery is facilitated through the battery commander and the battery operations center (BOC). The battery fire direction center (FDC) controls the firing of the battery and is required to maintain the current tactical situation and respond to the supported unit and higher headquarters. The BOC serves as a focal point for internal battery operations to include command and control, battery defense, coordinating logistics, and all other operational functions normally performed by a headquarters. It also serves as the alternate FDC by providing backup fire direction capability with the lightweight computer unit (LCU) or manual gunnery techniques. c. In a platoon-based (3 x 6 or 3 x 8) battery, the requirement for functional command and control exists at both platoon and battery levels. In the platoon, this requirement is met by the platoon operations center (POC). The POC is nothing more than the FDC with added operational responsibilities. The POC is not a separate element and does not require a separate vehicle. Its functions are supervised by the tire direction officer (FDO). Two of the functions of the POC are technical and tactical fire direction, the traditional functions of the FDC. Additional functions of the POC are reporting, accepting and executing orders from higher headquarters, coordinating logistics, and all the other operational functions normally performed by a headquarters. d. The BC of the platoon-based battery must also provide for a single point for command and control of the battery. Because the battery does not have the personnel or equipment to establish a separate BOC, the BC does this by designating an element within the firing battery, normally one of the POCs, to perform the battery operations fiction. In addition to its functions described above, the designated POC handles all tactical and logistical information and personnel and maintenance reports for the battery as a whole. One of the POCs should be designated as the casualty collection point for the battery and the medic is located with this POC. This POC may require augmentation to perform this function. The battery NBC noncommissioned officer (NCO) can provide this augmentation. By augmenting the POC in this manner, the NBC NCO also enhances his ability to perform his own monitoring and reporting functions.
Note: This manual will refer to the designated POC as a BOC to indicate that it is performing the BOC functions of a battery-based unit.
e. In a platoon-based firing battery, the location of the BOC and the battery trains must facilitate command, control and logistical support of the battery. There are three basic options

for positioning the battery elements. The options can be termed heavy-heavy, heavy-light, and light-light.
(1) Heavy-Heavy. This option divides the support elements in half and assigns them to each platoon. These elements should be dispersed in positions to the rear of the platoon position area to enhance survivability. Yet, they should be near the POC to facilitate coordination within the platoon.
(a) The advantages of this option are: Local security of both platoons is enhanced. Responsiveness of support elements to platoon is enhanced.
(b) The disadvantages are: More elements give a larger visual signature. Tracked and wheeled vehicles and thick- and thin-skinned vehicles are combined.
(2) Heavy-Light. This option positions all of the support elements in one platoon position area. These elements should locate near the FDC on the extremity of the position area.
(a) The advantages of this option are: Local security of one platoon is enhanced. Support is responsive to one platoon.
(b) The disadvantages are: One platoon has a larger visual signature. Maneuverability may be limited in one platoon area. Logistic support to the light platoon is decreased.
(3) Light-Light. This option positions all of the battery support elements in a separate location away from both platoon areas.
(a) The advantages of this option are: Each battery element has the smallest visual signature. Howitzer positioning and movement flexibility are maximized.
(b) The disadvantages are: Local security of platoons and battery elements is reduced. Combat service support (CSS) responsiveness is reduced.

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FM 6-50, MCWP 3-1.6.23

Section II
CANNON BATTERIES IN PLATOON-BASED FIELD ARTILLERY BATTALIONS

1-4. ORGANIZATION
a. An FA battalion with FA batteries organized into two firing platoons for platoon operations is considered a platoon-based organization. b. Each cannon battery in a platoon-based FA battalion consists of a battery headquarters and two firing platoons (Figure 1-1). This configuration allows for conduct of platoon operations.
(1) The battery headquarters has the personnel and equipment to perform administration, supply,

communications, NBC, and maintenance functions.
Note: Supply and NBC operations at the battery level are functions performed by personnel of the battery headquarters. There are not sections organized specifically for those functions. (2) Each firing platoon has the personnel and equipment to determine firing data, to fire the howitzers, and to resupply ammunition. (In some units, ammunition assets may be consolidated at battalion.)

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FM 6-50, MCWP 3-1.6.23

1-5. TACTICAL DUTIES OF KEY PERSONNEL
Paragraphs 1-6 through 1-12 present the suggested duties of key personnel in a cannon battery of a platoon-based battalion. The unit MTOE, the commander’s preference, personnel strength, and individual capabilities may require the commander to modify or reassign duties based on METT-T and standing operating procedures (SOPs).
1-6. BATTERY COMMANDER
The battery commander is responsible for all aspects of the operations of his battery. He locates where he can best command the battery, considering the factors of METT-T and the level of unit training. His responsibilities may include the following: a. Supervise and standardize the operations of the platoons. b. Reconnoiter and select platoon position areas after receiving direction from the controlling headquarters (Chapter 2). c. Determine the azimuth of fire if it is not given by higher headquarters. d. Plan and direct unit marches and movements in accordance with tactical plans established by higher headquarters (Chapter 2). e. Plan for survey control and, when necessary, conduct hasty survey (Chapter 5). f. Ensure an effective defense posture is maintained in the platoon areas (Chapter 3). g. Maintain communications and electronics security (Chapter 9). h. Plan for ammunition resupply (Chapter 12). i. Plan for logistic resupply of food service, supply, and maintenance items (Chapter 12). j. Keep the battalion TOC and battery personnel informed. k. Develop and execute the overall battery defense plan (Chapter 3). l. Supervise safety during battery operations and conduct risk assessment. m. Develop the battery standing operating procedure.
1-7. FIRST SERGEANT
The first sergeant (lSG) is the principal enlisted advisor to the battery commander. His responsibilities may include the following:

a. Supervise the platoon sergeants, gunnery sergeants, and section chiefs; and, whenever possible, maintain a presence on the gun line. b. Assist and advise during reconnaissance and selection of platoon position areas. c. Assist the commander in the development and execution of the overall battery defense plan (Chapter 3). d. Coordinate administrative and logistical support (less ammunition), to include water and food service, mail, laundry, showers, maintenance, and evacuation of personnel and equipment (Chapter 12). e. Monitor the health care, welfare, and sanitation of battery personnel. f. Plan, coordinate, and execute the evacuation of casualties to the battalion aid station.
1-8. PLATOON LEADER
The platoon leader (PL) is responsible for everything his platoon does or fails to do. He positions himself where he can best lead the platoon, considering the factors of METT-T. He relies heavily on the platoon sergeant to supervise the firing element and on the gunnery sergeant to supervise the detailed platoon RSOP. His responsibilities may include the following: a. Establish and maintain the firing capability of the platoon. b. Supervise the displacement, movement, and occupation of the platoon. c. Supervise the POC, and be prepared to perform the duties of the FDO to facilitate 24-hour operations. d. Supervise the use of the M90 radar chronograph. e. Supervise the overall maintenance of platoon equipment. f. Ensure continuous security of the platoon (with emphasis during displacement and occupation of position). g. Verify minimum (rein) quadrant elevation (QE) for each howitzer. h. Ensure the weapon location data are submitted and updated (on DA Form 5698-R [Weapon Location Data]) and DA Form 5969-R (Section Chief’s Report) is submitted to the POC.
Note: Reproducible copies of DA Forms 5698-R and 5969-R are at the back of this manual.

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FM 6-50, MCWP 3-1.6.23

i. Supervise and conduct hasty survey operations for the platoon. j. Supervise ammunition management within the platoon. k. Supervise safety during platoon operations. 1. Ensure all reports (personnel, supply, maintenance) are submitted to the battery commander and battalion.
1-9. FIRE DIRECTION OFFICER
The FDO is responsible for the training and supervision of POC personnel. He also must be familiar with the duties of the platoon leader, as he will at times perform his duties also. His responsibilities may include the following: a. Decide to attack a target, and issue a fire order. b. Ensure accurate and timely determination of firing data. c. Ensure that maintenance checks are performed on the section vehicle, radios, computer, and generators in strict compliance with technical manuals. d. Ensure that the tactical situation map is current. e. Ensure accurate FDC records of missions fired are maintained. f. Ensure that data for prearranged fires are disseminated and understood. g. Ensure data from the other platoon is recorded and available. h. Supervise assumption of control of the fires of the other platoon when necessary. i. Perform independent safety computations, and verify the data with the platoon leader. j. Maintain muzzle velocity (MV) information for all howitzers.
1-10. PLATOON SERGEANT
The platoon sergeant (PSG) is the primary enlisted assistant to the platoon leader and must be prepared to assume all of the platoon leader’s duties. His responsibilities may include the following: a. Supervise the firing platoon, and maintain firing capability. b. Supervise occupation of the position. c. Supervise the overall maintenance of the firing platoon. d. Develop and execute the platoon defense plan (Chapter 3).

e. Provide the 1SG with the platoon defense plan for integration into the overall battery defense scheme. f. Ensure that each chief of section knows the route to both alternate and supplementary positions. g. Verify the completion of DA Form 2408-4 (Weapon Record Data). h. Ensure ammunition is properly handled and protected. i. Ensure safety aids are used and safety procedures are followed.
1-11. GUNNERY SERGEANT
The gunnery sergeant (GSG) supervises and executes platoon advance party operations (Chapter 2). He must be prepared to assume the duties of the platoon sergeant. His responsibilities may include the following: a. Lay the platoon. b. Perform hasty survey as required. c. Initiate the development of the platoon defense plan. d. Assist in the sustainment of 24-hour operations. e. Ensure there is an initial fire direction capability with the advance party. f. Compute executive officer’s (XO’s) min QE for the lowest preferred charge the unit expects to fire.
1-12. HOWITZER SECTION CHIEF
The section chief is responsible for the training and proficiency of his section, the operational readiness of his equipment, and the safe firing of the howitzer. Appendix B presents sample tests to help in training the gunners. The section chiefs responsibilities may include the following a. Ensure the weapon is properly emplaced, laid, and prepared for action. The memory aid TLABSPAP will be used as a guide for the accomplishment of the following tasks:
T: Trails, spades, and/or firing platform properly emplaced. L: Lay weapon. A: Aiming point emplaced. B: Boresight verified or performed. S: Second circle. Verification of lay performed with a second aiming circle. P: Prefire checks on the weapon system performed.

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FM 6-50, MCWP 3-1.6.23
A: Ammunition prepared. P: Position improvement (site to crest determined, XO’s report rendered, alternate aiming points established, azimuth markers emplaced, camouflage, and defensive hardening of position).
Note: Unit SOP and the weapon technical manual will dictate when to dig in spades on towed weapons.
b. Ensure digital and voice communications with FDC are established and maintained. c. Ensure ammunition is properly segregated, stored, handled, and prepared. d. Ensure only safe data is fired by verifying firing data, correct sight picture, and bubbles centered. e. Ensure DA Form 4513 (Record of Missions Fired) is current, legible, and accurate (Chapter 7).

f. Maintain DA Form 2408-4, and compute and record equivalent full charge (EFC) data. g. Ensure DA Form 5969-R is completed for each position occupied. h. Ensure data on DA Form 5212-R (Gunner’s Reference Card) are correct and current.
Note: A reproducible copy of DA Form 5212-R is at the back of this manual.
i. Ensure range cards for the howitzer and crew-served weapons are properly prepared, and actively manage the assigned sector of the platoon defense plan. j. Ensure preventive maintenance checks and services (PMCS) are performed in accordance with the appropriate technical manual.

Section III
CANNON BATTERIES IN BATTERY-BASED FIELD ARTILLERY BATTALIONS

1-13. ORGANIZATION
a. A cannon battery in a battalion consisting of a headquarters battery, a service battery, and firing batteries (without TOE-designated platoons) is considered a battery-based battery. b. Each cannon battery in a battery-based FA battalion consists of a battery headquarters and a firing battery (Figure 1-2).
(1) The battery headquarters has the personnel and equipment to perform food service, supply, communications, NBC, and maintenance functions. (In some units, food service and maintenance may be consolidated at battalion.)
(2) The firing battery has the personnel and equipment to determine firing data, fire the howitzers, and resupply ammunition. (In some units, ammunition assets may be consolidated at battalion.)
1-14. TACTICAL DUTIES OF KEY PERSONNEL
Paragraphs 1-15 through 1-22 present recommended duties of key personnel in a cannon battery of a battery-based

battalion. The unit MTOE, personnel fills, and individual capabilities may require the commander to modify or reassign duties to fit his circumstances and SOPs.
Note: Key personnel in a US Marine Corps (USMC) battery have the same duties and responsibilities, except where noted.
1-15. BATTERY COMMANDER
The battery commander is responsible for all aspects of the operations of his battery. He must plan and train for continuous operations in an intense combat environment. He locates where he can best command the battery, considering the factors of METT-T and the level of unit training, His responsibilities may include the following: a. Supervise and standardize the operations of the battery. b. Reconnoiter and select battery positions (Chapter 2). c. Supervise the FDC when necessary.

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d. Plan specific actions to enhance the survivability of the battery (Chapter 3). e. Plan for survey control; and, when necessary, perform hasty survey (Chapter 5). f. Plan unit marches and movements (Chapter 2). g. Plan the basic load mix and the resupply actions for the battery. h. Plan logistics for the battery supply, mess, and maintenance (Chapter 12). i. Establish and maintain communications and electronics security (Chapter 9). j. Keep the battalion TOC and battery personnel informed. k. Develop and execute the overall battery defense plan (Chapter 3). l. Supervise safety during battery operations and conduct risk assessment. m. Develop the battery standing operating procedure.

FM 6-50, MCWP 3-1.6.23

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FM 6-50, MCWP 3-1.6.23
1-16. FIRST SERGEANT
The 1SG is the principal enlisted advisor to the battery commander. His responsibilities may include the following: a. Supervise the chief of firing battery and gunnery sergeant; and, whenever possible, maintain a presence on the gun line. b. Assist and advise the BC during reconnaissance and selection of the battery position. c. Assist the battery commander in the development and execution of the overall battery defense Plan (Chapter 3).
Note: In a USMC battery, the local security chief plans and executes overall battery defense. d. Coordinate administrative and logistical support (less ammunition), to include water and food service, mail, laundry, showers, maintenance, and evacuation of personnel and equipment (Chapter 12). e. Supervise the health care, welfare, and sanitation of battery personnel. f. Plan, coordinate, and execute the evacuation of casualties to the battalion aid station.
1-17. EXECUTIVE OFFICER
Usually, the XO commands the firing battery portion of the battery. As the position commander, he is responsible for everything the firing battery does or fails to do. During extended field operations, he spends part of his time supervising technical operations of the FDC. During this time, he relies heavily on the chief of firing battery to supervise the battery. Also, he relies on the GSG to lead the advance party. The XO’s responsibilities may include the following: a. Establish and maintain the firing capability of the battery. b. Supervise the displacement, movement and occupation of the battery. c. Supervise the use of the radar chronograph and overall MV management program of the battery. d. Supervise the maintenance of the battery equipment. e. Ensure continuous security of the battery (with emphasis during displacement and occupation of position). f. Verify minimum QE for each howitzer. g. Ensure that the weapon location data report is submitted and updated and that the section chiefs reports are submitted to the FDC. h. Supervise and conduct hasty survey operations for the battery.

i. Supervise the ammunition management for the battery. j. Supervise safety during battery operations.
1-18. ASSISTANT EXECUTIVE OFFICER (USMC only)
The assistant executive officer (AXO) assists the XO and FDO. He leads the BOC and assists the battery commander during displacement. His responsibilities include the following: a. Lay the battery. b. Perform hasty survey as required. c. Assume the duties of XO or FDO, when required. d. Assist in the establishment and maintenance of battery firing capability during advance party operations. e. Coordinate resupply and distribution of ammunition with the FDO. f. Perform liaison with battalion and other outside agencies, as required. g. Ensure there is initial fire direction capability with the advance party. h. Compute the XO’s min QE for the lowest preferred charge the unit expects to fire.
1-19. FIRE DIRECTION OFFICER
The fire direction officer is responsible for the training and supervision of the FDC personnel. He also must be familiar with the duties of the XO; since he will, at times, perform all those duties. His responsibilities may include the following: a. Decide to attack a target, and issue a fire order. b. Ensure accurate and timely determination of firing data. c. Ensure that maintenance checks are performed on the section vehicle, radios, computer, and generators in strict compliance with the technical manuals. d. Ensure that the tactical situation map is current. e. Ensure accurate FDC records of missions fired are maintained. f. Ensure that data for prearranged fires is disseminated and understood. g. Ensure data from the other batteries are recorded and available. h. Supervise assumption of control of the fires of other units when necessary.

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i. Perform independent safety computations, and verify the data with the executive officer. j. Maintain muzzle velocity information for all howitzers.
1-20. CHIEF OF FIRING BATTERY
The chief of firing battery (CFB) is the primary enlisted advisor to the XO and must be prepared to assume all of the XO’s duties. The equivalent USMC billet description is the battery gunnery sergeant (Btry GySgt). His responsibilities may include the following: a. Supervise and maintain the firing capability of the battery. b. Supervise the occupation of the position. c. Supervise the overall maintenance of the firing battery. d. Continue to develop and implement the battery defense plan. e. Give the 1SG information on the defense plan. f. Ensure that each chief of section knows the route to both alternate and supplementary positions. g. Verify the completion of the DA Form 2408-4. h. Ensure ammunition is properly handled and protected. i. Ensure safety aids and procedures are maintained. j. In a USMC battery, the battery gunnery sergeant will complete the NAVMC 10558A (gun book) and compute and record EFC data.
1-21. GUNNERY SERGEANT
The gunnery sergeant supervises and executes the battery advance party operations (Chapter 2). The equivalent USMC billet description is the local security chief. He must be prepared to assume the duties of the chief of firing battery or battery gunnery sergeant. Additional responsibilities may include the following: a. Lay the battery. b. Perform hasty survey as required. c. Initiate the development of the battery defense plan when necessary. d. Assist in the sustainment of 24 hour-operations. e. Ensure there is an initial fire direction capability with the advance party.

FM 6-50, MCWP 3-1.6.23
f. Compute the XO’s min QE for the lowest preferred charge the unit expects to fire. g. In a USMC battery, the local security chief plans and executes overall battery defense. The AXO lays the battery, performs hasty survey as required, ensures an initial fire direction capability with the advance party, and computes the XO min QE for the lowest preferred charge the unit expects to fire.
1-22. HOWITZER SECTION CHIEF
The section chief is responsible for the training and proficiency of his section, the operational readiness of his equipment, and the safe firing of his weapon. His responsibilities may include the following: a. Ensure the weapon is properly emplaced, laid, and prepared for action. The memory aid TLABSPAP will be used as a guide for accomplishment of the following tasks:
T: T rails, spades, and/or firing platform emplaced. L: L ay the weapon. A: A iming point emplaced. B: B oresight verified or performed. S: S econd circle. Verification of lay performed with a second aiming circle. P: Prefire checks in accordance with operator’s manual A: Ammunition prepared. P: Position improvement (site to crest determined, XO’s report rendered, alternate aiming points established, azimuth markers emplaced, camouflage, and defensive hardening of position).
Note: Unit SOP and the weapon technical manual will dictate when to dig in spades on towed weapons.
b. Ensure digital and voice communications with FDC are established and maintained. c. Ensure ammunition is properly segregated, stored, handled, and prepared. d. Ensure only safe data is fired by verify firing data, correct sight picture, and bubbles centered. e. Ensure DA Form 4513 is current, legible, and accurate (Chapter 7).

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FM 6-50, MCWP 3-1.6.23 f. Maintain the DA Form 2408-4, and compute and record EFC data. In a USMC batter, the battery gunnery sergeant will complete the NAVMC 10558A, and compute and record EFC data.
g. Ensure DA Form 5969-R is completed for each position occupied.

h. Ensure data are correct and current on DA Form 5212-R.
i. Ensure range cards for the howitzer and crew-served weapons are properly prepared, and actively manage assigned sector of the defense plan.
j. Ensure PMCS are performed in accordance with the appropriate technical manual.

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FM 6-50, MCWP 3-1.6.23

CHAPTER 2
RECONNAISSANCE, SELECTION, AND OCCUPATION OF A POSITION

This Chapter Implements STANAG 2041, QSTAG 520 and STANAG 2154/QSTAG 539.
Section I
RECONNAISSANCE AND THE ADVANCE PARTY

2-1. DEFINITION AND REQUIREMENTS
Reconnaissance, selection and occupation of position ensures the rapid and orderly movement to and occupation of a firing position. On the battlefield, a sophisticated enemy can locate and engage a battery in various ways. To survive, we may have to move often. Frequent movement, however, reduces responsiveness; it necessitates greater reliance on other batteries to assume the mission during displacement. To minimize movement time, all key personnel must be able to do the reconnaissance, selection, organization, occupation, and movement tasks quickly and efficiently. The key to a successful RSOP is discipline and team effort. Reconnaissance is the examination of the terrain to determine its suitability for use in accomplishing the mission.
2-2. CONSIDERATIONS
A continuous and aggressive reconnaissance is essential to timely and accurate fire support. The BC or his representative must continually perform this reconnaissance and plan ahead to meet any contingency. The BC must have a clear understanding of the tactical situation, of both friendly and enemy forces, while planning and executing any movement. The headquarters controlling the movement of the battery directs the essential elements of the movement—when, where, and how. The BC will advise the controlling headquarters of any factors to be considered in determining the essential elements of the move.
2-3. RECEIPT OF THE ORDER
The battery commander may receive movement orders ranging from a five-paragraph operation order (OPORD) to a simple authenticated radio message. A movement order from higher headquarters should include the general location of the new position, the azimuth of fire, no earlier than (NET) time the unit can cease firing capability, no later than (NLT) time to be in position ready to fire, route (if applicable), and any specific instructions (danger areas, intelligence, alternate positions, movement techniques). Unit

SOP should determine which, if any, of the above items are delegated to the battery commander.
2-4. ARTILLERY TROOP LEADING PROCEDURES
Troop leading procedures (TLPs) provide a mental framework to ensure complete preparation, dissemination and execution of the battery mission. The process provides a checklist for the commander from receipt of the mission to execution. The steps may occur out of order or simultaneously after receipt of the mission. a. Receive the Mission. Upon receipt of the FA support plan (FASP) or a warning order, the commander must analyze the mission in order to identify critical fire support tasks. He defines the task, purpose, method and success for each task to determine specific ammunition, logistics and unit preparation requirements. He should identify the precombat checks (PCCs) in priority that the sections must accomplish. A battery SOP should have PCCs that support routine tasks. These checklists streamline mission preparation. Finally, the commander needs to set a timeline for all critical events from issuing the warning order to execution. b. Issue the Warning Order. The commander takes his battery mission, critical fire support tasks, PCC priorities and timeline and issues a warning order to maximize battery preparation time. Even incomplete information can allow the sections to accomplish most of their required preparations. A modified five paragraph order works well. c. Make a Tentative Plan. The commander must gather information to make his plan by focusing on battery level METT-T and intelligence preparation of the battlefield (IPB), if available. The commander is concerned with positioning, movement, logistic support, rehearsals and defense as he makes his plan. d. Initiate Movement. If the mission requires repositioning, the commander should start his battery

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movement as early as possible (in accordance with METT-T) to make use of available time. e. Conduct Reconnaissance. Depending on METT-T, the reconnaissance may be a simple map reconnaissance. Ideally, it will consist of ground reconnaissance, establishing and verifying survey control, fully preparing the position to receive the battery, and developing the battery defense. Coordination for survey, engineer support, route security, adjacent unit coordination, and fire support can be accomplished. f. Complete the Plan. The commander must organize the information into a coherent order to issue to his sections. The level of detail is METT-T dependent, but as a minimum must convey the essential information to accomplish the critical fire support tasks. Prepare a terrain sketch or map board to use to issue the order. Rehearse to ensure a focused and clear delivery. g. Issue the Order. Key players must be present for the brief. Headquarters and BOC personnel should attend so they understand their role. Be concise, but specific in the subunit missions to each section. Once complete, use backbrief techniques to make sure your orders and priorities are understood. Have the XO and other key leaders back brief you after they have had time to analyze and implement their part of the plan. State the specific items you will check or have another leader check. Update your time line and rehearsal schedule. h. Supervise. This is the most important step. Leaders must conduct precombat inspections (PCIs) and spot-check the plan to ensure standards are met. In the defense especially, leaders must ensure weapons range cards, fighting positions, observation posts, and knowledge are to standard. Use subordinate leaders to assist, but the commander must conduct the priority PCIs. The requirements for effective PCIs are outlined in FM 7-123, pages 2-33 to 2-35.
Note: Appendix C of this manual provides a sample battery field artilley support plan checklist, sample precombat checklists, a sample warning order, a mission analysis work sheet, and a sample battery operations order.
2-5. RSOP OPERATIONS
The BC is responsible for the overall RSOP. He or his representative performs general reconnaissance and leads the advance party. He selects a battery or two firing platoon positions and a battery trains position (if applicable). The gunnery sergeants will then conduct the detailed RSOPs for their locations.

2-6. METHODS OF RECONNAISSANCE
The three methods by which the battery commander and platoon leaders may conduct a reconnaissance are map, air, and ground. The best reconnaissance is one which uses a combination of all three. Normally, the commander is able only to make a map inspection, followed by a ground reconnaissance. a. Map Reconnaissance.
(1) Any reconnaissance begins with a map inspection. Potential positions and routes to the new position can be chosen. This method is very fast and allows unsuitable routes to be eliminated. In addition, likely ambush sites can be identified on the map. The BC or platoon leader can also determine an initial order of march for the howitzers. The rule he applies here is that the howitzer which will travel the farthest into the new position will be the first vehicle in the column. There are also two major disadvantages to conducting only a map inspection:
(a) Terrain and other features may have been altered. For example, a bridge shown on the map may no longer exist. Military load classifications of bridges are not listed on maps. Bridges must be physically inspected.
(b) The surface conditions of the route and position cannot be determined. For example, the ground may not support an Ml09A3-A6 howitzer or an Ml98 howitzer and its prime mover.
(2) If available, aerial photographs should be used to supplement maps. They are usually more recent, show more detail, and present a clear picture of the current condition of the terrain to be crossed.
(3) In addition to aerial photographs, the battery commander can ask his battalion S2 or higher headquarters intelligence section for products from the terra-base computer program concerning his subsequent position areas and routes. b. Air Reconnaissance. If time and resources are available, information gained from an air reconnaissance may be very beneficial in the selection of routes to be used and areas to be occupied. Although a fast method, true surface conditions may not be distinguishable or may appear distorted. The battery commander must be careful that his flight plan does not compromise the route or the new position area. Normally this method will not be available to the battery commander. c. Ground Reconnaissance. The best method of reconnaissance is the ground reconnaissance. The suitability of routes can be physically examined. The true condition of the terrain is especially critical if the surface has been affected by enemy action (NBC attack) and/or weather

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conditions. The ground reconnaissance is the slowest method.
2-7. PLANNING THE RECONNAISSANCE
To maximize the tactical benefit, the reconnaissance must be thoroughly planned. As part of the planning phase for any operation order or RSOP, the factors of METT-T must be considered before any action is taken. a. Mission. The mission is the governing factor in planning the RSOP. The unit must remain able to perform its mission with minimal degradation as a result of tactical or survivability moves. The battery commander must perform, or have previously done, his mission analysis with respect to his current and subsequent positions. Then he can identify the battery’s critical tasks in each of these positions, and determine a list of movement and positioning criteria.
Movement Criteria Examples: The battery cannot lose firing capability. Therefore, the battery must move by platoon. Battery is out of range to execute their portion of the tire support plan. Therefore, move by battery using fastest movement technique. Battalion has two batteries moving at the same time. The battery could receive an emergency mission. Therefore, the battery must consider an internal platoon order of march and perform a reconnaissance of areas along the planned route to assist the battery on meeting this contingency.
b. Enemy Situation. The current enemy situation must be thoroughly understood. The disposition, intentions, and capabilities of enemy forces must be analyzed before the RSOP, particularly their local capabilities as revealed in current combat information.
Enemy Situation Examples: 1. If the most likely enemy action during the battery’s movement is from air attack, then:
The BC requests a change to the given route to support a terrain march for certain segments of the planned route where there is not adequate concealment for the battery. The route must allow the march units to conduct their immediate action drills for air attack. A route reconnaissance must be performed to determine easily identifiable features to serve as air target reference points (TRPs).

If a terrain march is too slow, move in an open column.
2. If the most dangerous enemy action during the battery’s movement is ambush, then:
Each march element, to include the reconnaissance and advance parties, must lead with an armored vehicle and/or crew served weapon. Coordinate with higher headquarters to determine possible ambush sites and clear those areas so that advance parties or main bodies can conduct reconnaissance by fire.
Positioning Criteria Examples: 1. If the most likely threat in the subsequent position is enemy counter-battery fire, then the battery commander must ensure position areas support maximum dispersion and hardening.
2. If the most dangerous threat to the battery in the subsequent position is from mechanized forces, then:
The battery commander must ensure the position is not located on platoon-sized or larger avenues of approach. He must perform a reconnaissance of possible observation posts (OP) to provide for early warning to execute hasty displacements or the activation of howitzer direct fire and/or tank-killer teams. He must make a reconnaissance of the position area for supplemental positions for howitzer direct fire and/or tank-killer teams. He must make a reconnaissance to determine if the position provides adequate defilade and terrain masking.
c. Terrain and Weather. The BC and/or platoon leaders must analyze the routes to be used by the unit assets and the time and distance required to make the move. The ability to move one firing platoon while keeping the other in position and firing is critical to the platoon-based operations and the accomplishment of the battery mission. Moving the battery over long, difficult routes requires well planned, coordinated movement orders and unit SOPs. The effects of the weather on the terrain to be crossed must be analyzed to facilitate rapid movement. Weather affects visibility (fog, haze) and trafficability (ice, rain-softened ground). d. Troops. The current troop strength and level of training must be considered. The mission may not change; but the troops available to accomplish it will. As the other factors of METT-T vary, so will the number of troops necessary

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to perform the mission. Because of casualties and these varying conditions, adjustments must be made during the planning phase. e. Time. The amount of time available for the RSOP will effect all phases of its accomplishment. The time factor will change due to events on the battlefield. Whether minutes or hours are allowed for the RSOP, adjustments must be made.
2-8. THE RECONNAISSANCE PARTY
The reconnaissance party should consist of enough individuals to accomplish successful RSOP. An example of a reconnaissance party is: the commander, the GSG, and representatives from each howitzer FDC; and support section. If enough survey or position azimuth determining system (PADS) sections are available, a survey capability

should be allocated to the commander. This capability will depend upon survey priority established by the battalion S3. The commander of a firing battery chooses position areas for the platoons or the battery and determines the azimuth of fire. The GSG then performs detailed position area RSOP.
2-9. ASSEMBLING THE ADVANCE PARTY
For either a deliberate or a hasty occupation, a prearranged signal or procedure should be used to alert and assemble the advance party. The signal should be in the unit SOPs, which will also list the personnel, equipment, vehicles, and place of assembly (see Tables 2-1 and 2-2). The advance party is normally assembled no later than the prepare-to-march-order phase.

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2-10. TAKING A FIRING CAPABILITY FORWARD
Depending upon the mission and tactical situation, the BC may direct that a howitzer section go forward with the advance party. Reasons for taking howitzers forward may be:
To confuse enemy moving target locating radars, as part of the infiltration plan. To determine the suitability of the route and firing position when conditions are doubtful. To conduct a registration or an offset registration.
2-11. MOVEMENT BRIEFING
a. Before departing to reconnoiter the new position, the BC briefs the platoon leaders and other key personnel on the movement information.
Situation: Enemy situation. Rear area activity. Major avenues of approach. Air activity. Potential ambush sites.
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Friendly situation. Changes in tactical missions and locations of friendly maneuver units and supporting artillery. Mission: Changes in the mission of the supported maneuver unit and supporting artillery. Execution: Concept of the operation. General location of the battery and/or platoon positions, azimuth of tire, routes, order of march, location of start point (SP) and RP and times. Mission-oriented protective posture (MOPP) status. Areas of known chemical and/or nuclear contamination. Administration and logistics: When and whereto feed unit personnel, priority for maintenance recovery, ammunition resupply, and refuel location. Command and signal: Command: Changes in location of the battalion command post (CP) and battalion support operations

center, and the location of battery commander. It also includes a contingency plan if the BC does not return or report back by a predetermined time or event. Signal: Movement radio frequencies and net control restrictions. Signals for immediate actions at the halt and during movement. b. After being briefed by the BC, the platoon leader or XO briefs the remaining key personnel by using the movement order format in Figure 2-1.
2-12. ROUTE RECONNAISSANCE
a. After making a map inspection, planning the reconnaissance, and briefing the necessary personnel,

FM 6-50, MCWP 3-1.6.23
the BC is now ready to make a ground reconnaissance. Accompanied by the advance party, the BC or his representative departs on the route reconnaissance. The primary purpose of this reconnaissance is to determine the suitability of the route of the units movement. Items to be analyzed include possible alternate routes, cover, concealment, location of obstacles, likely ambush sites, contaminated areas, route marking requirements, and the time and distance required to traverse the route. b. Once these areas are analyzed, any information considered pertinent should be sent back to the firing unit. Radio traffic must be carefully monitored to ensure that information does not compromise unit movement.

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Section II
SELECTING THE NEW POSITION

2-13. POSITION SELECTION CONSIDERATIONS
The BC selects a battery position or two firing platoon position areas and the battery trains area (if needed). Once the general areas have been determined, the gunnery sergeants conduct the detailed RSOP of their respective position areas and select alternate and supplementary positions. Position selection considerations are discussed below. a. Mission. This is the most important consideration. The position must facilitate tire throughout the maximum area of the supported maneuver force. b. Communications. The position must facilitate communications with stations within assigned and monitored radio nets. c. Defilade. Defilade is protection from enemy observation and direct fire weapons by use of a terrain mask. Defilade positions should be used; however they should not be so close to the mask that low-angle fire capabilities are restricted. d. Defensibility. The position should facilitate both active and passive defense so that it:
Can be entered without enemy observation. Offers effective cover and concealment, with emphasis on concealment. Also, survivability positions can also be dug by engineers to enhance both cover and concealment. Avoids high-speed enemy approaches. Has more than one entrance and exit route, preferably in the rear of the position.

e. Trafficability. Soil should be firm enough to support all vehicles. f. Weather. The effects of weather on terrain must be considered. g. Survey Control. Survey must be established or it must be available in a short amount of time.
2-14. TYPES OF POSITIONS
The BC or platoon leader must select primary, alternate, and supplementary positions. a. A primary position is one from which the firing element will accomplish its assigned mission. b. An alternate position is the one to which the unit moves in case its primary position becomes untenable. Since the unit will continue its mission from the alternate position, it must meet the same requirements as the primary position and should be far enough away to escape the effects of enemy indirect fire on the primary position. It should be reconnoitered and prepared for occupation. Each section chief must know the route to the alternate position, because movement to that position may be by section. c. A supplementary position is one selected for accomplishment of a specific mission, such as offset registration, adjustment with a roving gun, or defense of the primary position.
(1) Supplementary position(s) for defense should be selected to cover likely enemy avenues of approach.
(2) Position(s) for offset registrations and roving guns should be far enough away so that counterfire will not affect the primary position.

Section III
ORGANIZING THE NEW POSITION

2-15. ADVANCE PARTY PREPARATIONS
a. Having arrived in the new position area, the advance party conducts a security sweep and prepares the position for occupation. The purpose of the advance party security sweep is to perform position area reconnaissance to confirm its suitability for occupation by the main body in accordance

with METT-T and the absence of enemy, mines, booby traps, NBC hazards, and so on. Natural cover must be used to the maximum. Security is continuous throughout advance party operations. b. The advance party is not normally manned or equipped to clear areas of organized enemy activity, mines, or NBC hazards. If these threats or conditions are present in the

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proposed position area, the advance party breaks contact with any enemy forces or marks minefield and hazards and moves on to find another position area. The battery commander can coordinate for additional assets, or augment the advance party with internal assets, to provide the additional ability to clear areas of small enemy forces, obstacles, and minefield.
c. The following are some tactics, techniques, procedures, and considerations units should incorporate when performing advance party security sweeps.
(1) Maximum use of the senses: (a) Sight. Advance party members look for: Enemy personnel, vehicles, and aircraft. Sudden or unusual movement. Smoke or dust. Engine exhaust fumes. Unusual movement of farm or wild animals. Vehicle tracks. Signs or evidence of enemy occupation. Recently cut foliage or vegetation. Lights, fires, or reflections. Muzzle flashes.
(b) Hearing. Advance party members listen for: Running engines. Track sounds. Voices. Metallic sounds. Gunfire. Dismounted movement through brush or woods.
(c) Smell. Advance party members smell for: Cooking food. Vehicle exhaust. Burning petroleum products. Burning tobacco products.
d. Advance parties use reconnaissance methods that they have trained and rehearsed in detail. The correct reconnaissance technique will maximize security and mission accomplishment.

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(1) Mounted reconnaissance of a position area should be used when:
Terrain is open and provides maximum visibility. Time is limited. Very detailed reconnaissance is not required. Minefield and obstacles in the area are not expected. Enemy contact is not likely. The advantages of a mounted reconnaissance include: Speed. The use of the advance party vehicle, depending on which type of vehicle is used (radio, GPS, possible armor protection, firepower). Easy to break contact and move on. The disadvantages of a mounted reconnaissance include: Loss of stealth. Loss of some reconnaissance detail. (2) Dismounted reconnaissanceis used when: Detailed reconnaissance is required. Maximum stealth is necessary. Enemy contact is expected or likely. Terrain is restrictive or is surrounded by wooded areas. Time is not limited. Mines are likely in the area. The advantages of a dismounted reconnaissance include: Allows the advance party to obtain detailed information about the position area. Less chance of enemy stay-behind forces remaining undetected. Allows for maximum security of the advance party. The disadvantages of a dismounted reconnaissance include: Time consuming. Difficult to overwatch entire advance party with a crew-served weapon. Advance party is removed from the support of their vehicle (comm, GPS, and so on). More difficult to command and control. (3) In reconnaissance by fire, advance parties place direct tire on positions where there is a reasonable suspicion of enemy occupation; the goal is to cause the enemy to
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disclose his presence by movement or returning fire. Advance parties use this technique when enemy contact is expected and time is limited. Reconnaissance by fire does not work in all cases. For example, disciplined troops in prepared positions will not react to the advance party’s tires. Some situations in which reconnaissance by fire may be employed include:
Bunker complexes that mayor may not be occupied. Existence of an obvious enemy kill zone. Signs of recent enemy activity. Key considerations for reconnaissance by fire include: Indirect fire is very difficult to coordinate and requires much more time to execute and control. Direct fire will disclose the advance party’s location. Requires a high degree of situational awareness to ensure that no friendly units are fired upon or return fire.
(4) Some situations might dictate a combination of mounted and dismounted reconnaissance. In any case, battery commanders and gunnery sergeants can use the following guidelines to ensure maximum security and mission accomplishment:
Always use an element with appropriate firepower to overwatch the reconnaissance party. If possible, use prominent terrain to gain a vantage point to visually sweep the area with binoculars or night vision devices prior to entering. If dismounting, select a concealed, secure, dismount site well outside the position area. Develop and rehearse a contingency plan for each security sweep. e. The following are positioned in the battery or firing platoon area:
Howitzer locations. The aiming circle. FDC or POC. MX-155 or TM-184 terminal strip. M8A1 automatic chemical agent alarm.
f. If the battery support elements are present, they will be positioned with full consideration for survivability and operability as the tactical situation dictates. FM 6-20-1

presents information and guidance on determining positions for CSS elements.
2-16. FORMATIONS
a. The factors of METT-T must always be considered when howitzers are emplaced. The main emphasis is on mission and enemy. The artillery will most likely face a general threat of counterfire, air attack, ground attack, and radio electronic combat. To counter that threat, the BC or platoon leader must consider techniques such as dispersion, movement, hardening, and concealment when selecting positions for his howitzer.
b. The enemy counterfire threat and air attack threat may be so great that the BC or platoon leader will consider dispersing his howitzers over a large area and maximizing the natural cover and concealment offered by the local terrain. This type of howitzer positioning is called terrain gun positioning (Figure 2-2). The capabilities of the LCU and battery computer system (BCS) to compute individual piece locations have enhanced terrain gun positioning. c. The enemy ground attack, guerrilla, and special forces threats may cause the BC to position the howitzers in a tight and defensible position area. Key personnel in the battery must consider hardening and unit defense. The diamond formation in platoon-based units (Figure 2-3) and the star formation in battery-based units (Figure 2-4, page 2-12) are optimal in these circumstances. They provide excellent 6400-mil firing and unit defense capabilities. d. Linear formations such as the "line" and "lazy W" can best be used during situations such as emergency and hasty occupations which require immediate fire support. These formations provide an optimum standard sheaf in the target area and offer excellent command and control. However, they are vulnerable to air attack. Position improvement such as dispersion and concealment should be considered as time and the tactical situation permit. e. The bumper number of a particular howitzer section is associated with each howitzer number (1 through 8). This association does not change from position to position. If a howitzer becomes disabled or lost en route to a new location, its associated howitzer number and all other howitzer numbers do not change. For example, once a weapon is designated Number 7, it remains Number 7. The LCU and BCS are initialized with individual howitzer muzzle velocity data which corresponds to a specific howitzer. Use of this procedure allows convenience in referring to pieces based on location and at the same time eliminates the requirement to vary the data base in each position. The howitzers are numbered from right to left and from front to rear when facing the azimuth of fire.

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Section IV
PREPARATION FOR OCCUPATION

2-17. DAYTIME OCCUPATION
a. The BC finalizes his plan of occupation. He gives priority to performing those tasks that facilitate immediate fire support. The plan is not limited to, but should include, the following:
The general location for the FDC or POC and howitzer positions. The azimuth of tire materialized by a terrain feature or by pointing his vehicle in the direction of fire. Entrance and exit points and guidance to the gunnery sergeant for the track plan. Guidance on the scheme of defense.

Location of the ground guide pickup point. b. The first sergeant or gunnery sergeant establishes the track plan, organizes the vehicle dispersal area, selects a position for each element in the service area, and plans the defense of the position. Considerations are as follows:
(1) Use existing roads. (2) Select separate exit and entrance routes. (3) Ensure routes follow natural terrain features such as gullies and tree lines and take advantage of natural overhead cover and concealment. (4) Brief vehicle guides on the track plan. If concealment is critical, the gunnery sergeant may dictate

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the exact route of each vehicle. In SP units, sharp pivoting, which will disrupt ground cover, must be avoided. c. The gunnery sergeant does the following:
(1) He sets up and orients the aiming circle where it will have line of sight to the howitzers. If survey is available, he directs the survey team to emplace an orienting station (ORSTA) where it will have line of sight to the howitzers and an end of orienting line (EOL) where it can be easily identified from the ORSTA. Additionally, he briefs the survey team on any marking requirements, in addition to unit SOP, necessary for the EOL. He then sets up the aiming circle over the ORSTA and verifies survey, by measuring the azimuth to the EOL (direction) and map spot/GPS (position and altitude), before releasing the survey team.
(2) As soon as the gun guides emplace panoramic telescope (pantel) marking stakes, the gunnery sergeant measures and records the initial deflection to each stake and records the azimuth (az) to the howitzer on DA Form 2698-R

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(Figure 2-5). Priority is to announce the initial deflection to each gun guide over the wire line to check communications. If wire is not in, gun guides will come to the aiming circle and record the initial deflection. The gun guide gives his initial deflection to his gunner and section when the platoon arrives.
(3) He determines the distance and the vertical angle (VA) to each howitzer (see Chapter 4).
(4) Having determined the deflection, VA, and distance from the aiming circle to each weapon, the gunnery sergeant gives the data (Figure 2-5) to the FDC representative. The data are applied to the M-17 plotting board for computation of TGPCs (see Appendix D).
(5) He obtains site to crest and piece to crest range from each gun guide. He then determines XO’s min QE for the lowest preferred charge the unit expects to fire in the position. Add a 20 mil safety factor to allow for the accuracy of the M2 compass.

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d. Each gun guide does the following: (1) He emplaces the pantel marking stake in the
designated location. This stake marks the location of the pantel of the weapon.
(2) He stops the weapon parallel to the guide stake or tape so that when the weapon is emplaced, the pantel will

be over the hole left by the pantel marking stake. The proper emplacement of the pantel marking stake and guide stakes for SP units is shown in Figure 2-6 and for towed units in Figure 2-7.
(3) Lays wire from the TM-184 to his cannon position and hooks up to his TA-312 telephone.

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(4) Receives and records the deflection to his pantel marking stake.
(5) He helps the GSG determine the distance from the aiming circle to his gun position. The primary means of determining distance from the aiming circle to each howitzer position is the subtense method, With this technique, the gun guide positions a 2-meter subtense bar (see Table 5-6, page 5-16) or M-16 rifle (see Table 5-7, page 5-17) over the pantel marking stake while the GSG measures the angle. If necessary, the gun guide paces the distance from his howitzer position to the aiming circle and reports the distance to the GSG. He double-checks the distance by pacing back from the aiming circle to the pantel marking stake.
(6) He determines site to crest by using the M2 compass or M2A2 aiming circle (see chapter 4). He then determines piece-to-crest range and relays site to crest and piece-to-crest range to the GSG.
(7) He walks the track plan as directed by the GSG. He walks the selected route from the battery or platoon entry point to the howitzer position and makes sure that there are no obstacles. He uses the existing roads and trails. Selected routes should follow natural terrain features, such as gullies and tree lines, and should take advantage of cover and concealment.
(8) He takes up a defensive position as directed by the GSG.
(9) He and the other gun guides assemble at the pickup point when directed by the GSG. e. The FDC or POC representative does the following:
Emplaces the TM-184 (when the communications representative is not present). Lays wire from the TM- 184 to the FDC position. Guides the FDC or POC vehicle into position. Erects the OE-254 antenna. Over a secure radio, relays survey and lay data to the main body. f. The communications representative does the following: Emplaces the TM-184. Ensures that all other wire lines are laid, tagged, and properly connected to the TM-184, and lays wire to the aiming circle. Assists with erection of the OE-254 antenna.

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Note: The communications representative’s first priority is to establish internal wire communications to transmit firing data. His second priority is to establish communications with outposts and make drops at various other locations the GSG indicates.
2-18. LIMITED TIME PREPARATIONS
a. When the advance party has limited time to prepare a position, the BC or GSG must establish priority tasks. As a minimum, he must ensure the following:
(1) Cannon positions are selected. (2) Aiming circle is set up. (3) Cannon positions are prepared, to include placing of howitzer and pantel marking stakes and recording of initial deflections. (4) Minimum essential internal wire communications are established. (5) Attempt is made to pass survey and lay data to the main body. b. Duties are decentralized. As soon as the BC or GSG selects the position, the gun guides select positions for their howitzers. c. The battery commander’s or GSG’s driver is left at the release point to guide the entire platoon into position. Gun guides meet their vehicles as they approach their positions. d. The FDC or POC representative and the GSG conduct their normal duties as much as time permits.
2-19. NIGHT OCCUPATION
Night occupation priorities are similar to daylight occupations. However, they require more planning, more time, and additional techniques to ensure a smooth and orderly occupation. a. Gunnery Sergeant. The GSG is especially concerned with noise and light discipline, security, and communications between advance party members. b. Gun Guides. Guides must be thoroughly briefed and should pace their routes before and after darkness. They should be equipped with filtered flashlights to guide the vehicles. Color coding of individual howitzer sections will facilitate section identification during night operations (example: first or fifth section-blue, second or sixth section-red, third or seventh section-yellow, and forth or eighth section-green). Light discipline must be controlled.

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2-20. SECTION CHIEF’S REPORT
a. DA Form 5969-R (samples in Figures 2-8 and 2-9) enables the platoon leader to consolidate information in preparation of his report and in his determination and verification of the minimum QE. The report should contain the following information:
Date-time group (DTG). Howitzer number and bumper number. Azimuth of fire. Lay deflection (from the lay circle or other howitzer number). Distance from the lay circle to the howitzer. Site to crest (in mils). Distance to crest (in meters).

Crest object (such as a tree or ridge line). Minimum quadrant elevation. Maximum quadrant elevation. Left and right deflection limits. Propellant temperature. Sensitive items. Ammunition status, which consists of projectile types, square weights, amounts, and lot numbers; fuze types and amounts; and primer types and amounts.
b. The report is required for each position area or firing point occupied. For centralized control of the report, the section chief will submit the report directly to the FDC. The position commander and FDO will take necessary actions.

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Section V
TACTICAL MARCHES

2-21. METHODS OF MOVEMENT
A tactical march is the movement of a unit or elements of a unit under actual or simulated combat conditions. There are several methods of moving the platoon in a tactical configuration. Each method has its specific advantages and disadvantages. The BC or platoon leader decides which method or combination of methods is best. The methods discussed in this section are open column, close column, infiltration, and terrain march.
2-22. OPEN COLUMN
The open column road movement is used for daylight movements when there is an adequate road network that is not overcrowded, when enemy detection is not likely, when time is an important factor, and when there is considerable travel distance involved. Vehicle interval in an open column is generally 100 meters. a. Advantages of this method are as follows:
Speed (the fastest method of march). Reduced driver fatigue. Improved vision on dusty roads. Ease in passing individual vehicles. Ease in dispersing vehicles as a passive defense measure against an air attack. Less chance of the entire unit being ambushed. b. Disadvantages of this method are as follows: Greater column length requires more road space. Other traffic often becomes interspersed in the column. Communication within the column is complicated.
2-23. CLOSE COLUMN
For close column movement, the vehicle interval is less than 100 meters. At night each driver can observe the "cat-eyes" of the blackout markers on the vehicle in front of him and maintain an interval of 20 to 50 meters (Figure 2-10). If the driver sees two marker lights, the interval is too great. If the driver sees eight marker lights, he is too close. If the driver sees four marker lights, he is maintaining the proper interval. During daylight, close column is used when there is a need for maximum command and control; for

example, during periods of limited visibility or when moving through built-up or congested areas. a. Advantages of this method are as follows:
Simplicity of command and control. Reduced column length. Concentration of defensive firepower. b. Disadvantages of this method are as follows: Column is vulnerable to enemy observation and attack. Strength and nature of the column are quickly apparent to enemy observers. Convoy speed is reduced. Driver fatigue increases.

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2-24. INFILTRATION
When the platoon moves by infiltration, vehicles are dispatched individually or in small groups without reference to a march table. This technique is time-consuming and the vehicles are difficult to control. It is used when the enemy has good target acquisition means and quick reaction capabilities. a. Advantages of this method are as follows:
Least vulnerable to hostile observation. Ideal for covert operations. Provides passive defense against air and artillery attack. Deceives the enemy as to the size of the unit. b. Disadvantages of this method are as follows: Time-consuming. Most difficult to command and control. Small elements are more vulnerable to ground attack. Individual vehicles may get lost.
2-25. TERRAIN MARCH
The terrain march is an off-road movement. A unit using this type of movement should travel close to tree lines, along gullies, and close to hill masses (see Figure 2-11). A terrain march should be conducted when enemy observation or interdiction by artillery fire or air attack is likely. A platoon may move safely on a road for some distance and change to a terrain march at a point where enemy observation becomes likely or vehicle congestion provides the enemy an inviting target. a. Advantages of this method are as follows:
Strength and nature of a column are difficult to determine. Avoids traffic. Provides passive defense against air and artillery attack.

FM 6-50, MCWP 3-1.6.23
b. Disadvantages of this method are as follows: Displacement time may be increased. Ground reconnaissance is required. Soil conditions may complicate this type of movement. Improper movement leaves wheel or track marks to the new position. Extensive coordination is required to avoid traveling through other unit areas. -
c. The battery using the terrain march may move in open or close column or by infiltration. The battery can displace either as a unit or by echelon. Continuous fire support is essential.

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FM 6-50, MCWP 3-1.6.23

Section VI
PREPARING FOR MOVEMENT

2-26. ORDERS
The details given in a march order depend on the time available, the tactical situation, and traffic conditions. The order may be supplemented by strip maps, sketches, and march tables. The main items in a march order are based on the battery commander’s reconnaissance order. They are as follows:
Situation. Mission. Destination. Organization, to include order of march and composition of the column. Instructions from the XO or platoon leader to the main body. These should include start point, checkpoints, designated rally points, release point, times for arrival at and clearance of these points, rate of march, vehicle interval, route of march, order of march, and review of immediate actions to take in case of trouble. General instructions regarding restrictions on use of roads, maximum speed of march units, catch-up speeds, alternate routes, detours, use of lights and any special instructions regarding march discipline or defense against air or ground attack. Communication instructions regarding the use of radio, messengers, flags, whistle or horn signals, pyrotechnic signals, and hand and arm signals.
2-27. LOAD PLANS
A load plan prescribes efficient loading of personnel and equipment for movement. Each vehicle should have one. A good load plan is insurance that a unit will move into the new position with all its equipment. The load plan for a vehicle must be such that the equipment most essential to the mission is loaded last. The load plan should be recorded and graphically portrayed. Load plans should be identical between like sections within the same battalion. The load plan should be combat configured (complete rounds), based on the "go to war" basic load. Steps in preparing the load plan include the following:
Examining the battery TOE to determine the personnel, equipment, and vehicles authorized for each section.

Carrying non-TOE property in the section responsible for using it. Listing the personnel and equipment to be carried in each vehicle. Equipment should be located to facilitate identification under blackout conditions. Practice loadings to test the validity of the load plan. Establishing a list of items that must be removed from. the vehicle and carried forward if the vehicle becomes disabled. Using load plans. Operator manuals and Appendix E of this publication present examples. Indicating that howitzers and ammunition vehicles use separate camouflage nets.
2-28. MOVEMENT PREPARATIONS
When the command PREPARE TO MARCH ORDER is given, everything possible will be done to quickly displace the unit. However, these actions must not hamper the ability to continue to deliver tire. Actions may include, but are not limited to, the following: a. Stow section equipment.
Note: The collimator and any equipment or item forward of the howitzers remains in place until receipt of the final command MARCH-ORDER.
b. Upload all ammunition. Transload ammunition from the ammunition vehicle to the howitzer to allow maximum ammunition availability at the next position. c. Stow camouflage nets. d. Load all service elements (mess, maintenance, and so forth). e. Ensure that security is continuous.
2-29. ORGANIZATION OF THE COLUMN
The organization of the battery or platoon column varies according to the tactical situation, the threat, and the position area to be occupied. The following points should be considered: a. In areas where enemy attack is probable, the cannons should be dispersed throughout the entire column.

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FM 6-50, MCWP 3-1.6.23

b. If feasible, there should be two air guards per vehicle. One scans the sky forward of the vehicle while the other scans the sky rearward. c. Machine guns should be distributed evenly throughout the column and should be aimed alternately to the left and right sides of the route of march.

d. Unit instructions should specify that some personnel fire 3-5 round bursts and some personnel fire on semiautomatic to maintain continuous fire. e. The NBC detecting and monitoring equipment should be located with the lead vehicle of the convoy. The unit could upgrade its MOPP level during movement.

Section VII
CONDUCTING THE MARCH

2-30. MARCH DISCIPLINE
a. Officers and NCOs ride where they can best control the march. The senior person in each vehicle is responsible for ensuring that all orders concerning the march are carried out. b. Key personnel should disperse throughout the column. This should preclude losing a disproportionate number of these persons as a result of enemy action. c. The column must keep moving. Procedures for the pick up of mission-essential personnel and equipment if a vehicle breaks down should be indicated in the unit SOP. For example, the driver stays with the vehicle and the maintenance representative stops to help. If the disabled vehicle cannot be repaired in a reasonable time or recovered by the platoon, the position and condition of the vehicle are reported to the BC for recovery. The maintenance representative must proceed along the route of march as soon as possible to be available to the rest of the platoon. d. Each vehicle commander is responsible to watch for signs, markers, signals, and other traffic. e. The specific objective of march discipline is to ensure intelligent cooperation and effective teamwork by march personnel. Teamwork includes the following:
Immediate and effective response to all signals. Prompt relaying of all signals. Obedience to traffic regulations and control personnel. Use of cover, concealment, camouflage, dispersion, blackout precautions, smoke, and other protective measures against air, ground, armor, and NBC attack. Maintaining correct speeds, positioning, and intervals between vehicles within the column. Ability to recognize route marking signals and signs.

2-31. CONVOY CONTROL MEASURES
The control measures discussed below help in convoy movement: a. The start point is normally a geographical feature identifiable on the ground and on a map. The first vehicle of the convoy must cross the start point at the specified start time. The BC is responsible for determining the route to the start point and the time it will take to get there. If the unit is displacing as part of a battalion move, the start point is also the point at which control of the marching element is normally assumed by battalion. b. Normally, a checkpoint is a geographical feature identifiable on the ground and on a map. It is used in reporting progress along the route of march. It may be used as a target when planning fires in defense of the convoy. c. Normally, the release point is normally a geographical feature identifiable on the ground and on a map. The last vehicle of a convoy must cross the RP at the specified time. The BC is responsible for determining the route from the RP to the new position area. If the unit is displacing as part of a battalion move, the RP is also the point at which control of the marching element is regained by the platoon. The BC or GSG may send a vehicle from the advance party to the release point to lead the unit into the new position area. d. A pickup point is a location, normally within the position, where the gun guide meets the howitzer and guides it into position. e. Normally, a rally point is a geographical feature identifiable on the ground and on a map. It is used as a point of assembly and recovery from dispersion due to enemy attack. The designated rally point(s) should be located near or on the alternate route to the new position. f. Route marking aids in the move. The route-marking detail marks the route by posting signs and/or personnel at those critical locations where elements of the march might

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FM 6-50, MCWP 3-1.6.23

make a wrong turn. Details concerning traffic control and route marking are presented in FM 55-30 and FM 19-25. g. Predetermined signals should be established to aid in convoy control. Colored flags in daylight and flashlights at night can aid in simple but important communications within the column. (See FM 21-60.)
2-32. HALTS
a. During administrative marches, halts are made at regular intervals or at selected sites. They allow personnel to rest, to service the vehicles, and to check the loads. Normally, halts are not scheduled for tactical marches. b. During extended vehicle marches, wooded areas, built-up areas, and appropriate terrain should be selected as halting places. They provide concealment and do not present a straight line of vehicles for attack by enemy aircraft. Avoid stopping near crossroads, railroads, and other easily identifiable reference points.
2-33. MARCH COLUMN CONTINGENCIES
a. Immediate Action Procedures.A unit must always assume that it is a high-priority target and vulnerable to all kinds of attack while moving. Preplanned immediate actions can decrease vulnerability. In establishing immediate action procedures, the BC or platoon leader should consider the following:
The enemy situation-with what he expects to be attacked. The organic resources for countering the different types of attack. The nonorganic support available for countering attacks. The amount of time available for training the platoon in the particular immediate actions (for example, infantry squad tactics in response to a blocked ambush). The type of communications to be employed with the immediate actions-flags, radio, arm and hand signals, and so forth. How best to neutralize the attack. Planned tires along the route of march. In all cases of enemy attack, conduct immediate action procedures and then report the situation to higher headquarters. b. March Column Under Artillery Attack. The immediate actions in defense against hostile artillery fire are to move out of the danger zone, report the situation to

higher headquarters, and request immediate counterfire. If a platoon expects hostile artillery tire during the march, it can reduce its vulnerability by moving-
By open column or infiltration. Under the cover of darkness or during other periods of reduced visibility. By terrain march. c. March Column Under Air Attack. In the event of an air attack, all available personnel should engage the aircraft immediately. On order of the convoy commander, the column either disperses or halts. If ordered to halt, vehicles should disperse alternately off both sides of the road. A high-performance aircraft cannot be engaged effectively by leading it with low-volume, independent small arms fire. As the aircraft approach, all personnel fire their weapons in the air to form a wall of bullets through which the aircraft must fly. d. Roadblocks. An element may be halted by a roadblock. The maximum amount of firepower available, including howitzer direct fire, should be placed immediately on the roadblock and on both sides of the roadblock. If nonorganic support, such as close air support, covering artillery, or armor is available, it should be called on immediately to help. If the roadblock cannot be neutralized, the unit must try to disengage under cover of supporting fires. Upon disengaging, the element should meet at a designated rally point and resume its march by an alternate route. An attempt to crash vehicles through a roadblock before it is checked for mines may result in unnecessary losses and a complete blocking off of the road by disabled vehicles. e. Ambush. (1) There are two types of ambushes-blocked and unblocked. Both must be countered in the same manner-get out of the kill zone, neutralize the ambushing force with firepower, and report.
(a) Blocked ambush. If the route is blocked, maximum available fire should be placed immediately on the attacking forces. Personnel in the kill zone should immediately dismount, attack as infantry and report. Staying in the kill zone is the worst course of action. The portion of the element that is not in the kill zone must also react immediately. There are few ambushing forces that can equal the organic firepower of an artillery unit. Use the howitzers to place fire on the ambushing force; then roll up the flanks of the enemy.
(b) Unblocked ambush. In an unblocked ambush, the element should increase speed and move through the ambush area while placing the maximum amount of small arms and automatic weapons fire on the attackers and report.

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FM 6-50, MCWP 3-1.6.23

(2) A consideration in employment of the main armament of the howitzer from the kill zone is that the targets may be too close for proper fuze action. Only the 105-mm antipersonnel round (M546) can be set for muzzle action to engage targets close to the weapon.
(3) If the area was identified during the map inspection as a likely ambush site, on-call fires are executed. Otherwise, a fire request is sent immediately to the battalion FDC.
(4) If the ambush or any other enemy action is of such magnitude as to cause the column to break up, individual elements should proceed to the new position or designated rally point on their own.
2-34. OTHER MOVEMENTS
a. Detailed descriptions of the various types of movements and marches are in the following manuals:
FM 55-30, which includes information on the organization of motor movements, the movement of personnel, and the planning of motor movements. FM 100-50. FM 101-10-1, which includes planning guidance for movements. b. When the unit moves by rail, air, or water, it normally moves as an element of the FA battalion or with a supported unit. In any case, the battery receives detailed instructions in the form of a movement order or pertinent extracts from

the movement order. A warning order alerts the battery and gives enough information of the impending movement for the battery to make plans and to take the necessary preliminary action. The references listed below provide adequate information for the following types of movement:
Movement by rail-FM 55-15, TM 55-601. Movement by air—FM 55-9, FM 55-12, FM 90-4, and FM 101-10-1. Movement by water—FM 55-15 and FM 101-10-1.
2-35. MOVEMENT PROCEDURES
The BC ensures that movement procedures are included in the unit SOPs. He should consider the following items before establishing a movement SOP:
Tips on establishing a realistic movement SOP (paragraph 2-41). References identified in this chapter. STANAG 2041 and QSTAG 520, Operation Orders, Tables and Graphs for-Road Movement (see FM 55-30 for applicable details). STANAG 2154 and QSTAG 539, Regulations for Military Motor Vehicle Movement by Road The applicable details of this agreement to be included in unit SOPs are extracted from STANAG 2154 and are shown below.

EXTRACT STANAG 2154 (Edition 6) REGULATIONS FOR MILITARY MOTOR VEHICLE MOVEMENT
BY ROAD
5. Composition of Columns. a. A column may be composed of a number of organized elements. b. Each organized element includes: (1) A commander whose location may vary. (2) In the first vehicle: a subordinate commander known as the pace setter. (3) At the end a subordinate commander known as the trail officer. c. A reporting officer* is to precede each column. His fiction is to report the details of the column to each traftic control post or border crossing point as applicable. d. A reporting officer* (who may be the trail officer) is to be appointed to report to each traffic control post once the column has passed, giving details of any occurrences including vehicle casualties. e. Each vehicle must have a vehicle commander, who may be the driver. He is responsible for both crew discipline and the execution of the mission.
* May be of any rank as considered appropriate by the column commander.

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FM 6-50, MCWP 3-1.6.23
6. Identification of Columns. a. Movement Number (Example at Annex A). (1) Each column which has been allocated a movement credit must be identified by a number known as the "movement number." This number identifies the column during the whole of the movement, including the crossing of national boundaries. (2) The movement number is to be placed on both sides of each vehicle. It must be permanently legible, from ground level, at a minimum distance of 6 meters in normal daylight. (3) The movement number must be white or yellow and remain legible in all weather during the whole movement. It must be removed as soon as the movement is completed. b. Minimum Lighting and Flagging. (1) In peacetime, headlights of all vehicles moving in the column must be on at all times (low beam). (2) The first vehicle of each element must display a blue flag mounted on the front left-hand side of the vehicle. (3) The last vehicle of each element must display a green flag mounted on the front left-hand side of the vehicle. (4) The column commander should display a white and black flag at the front left-hand side as indicated below:
(5) The driver of a broken down vehicle must remove the flag(s) and filter (light) and if technical assistance is required, a yellow flag is to be attached to the vehicle so that it is visible to approaching traffic.
(6) Flags must be approximately 30 cm (12 in) x 45 cm (18 in) in size. (7) To obtain legal rights for column movements for different countries, see Annex D. 7. Movement Credit. A movement credit is issued by the National Movement Staff or the appropriate authority, on whose territory the movement starts. The credit is coordinated by that staff or authority with the movement staff or authority of another nation where the crossing of international boundaries is concerned. It is required for: a. Columns of vehicles in accordance with national regulations (see Annex C). b. Outsize or heavy vehicles in accordance with national regulations (see Annex B). c. In the case of border crossing movement, see STANAG 2176. d. Hazardous cargo (in accordance with national/military regulations). 8. Special Regulations for the Execution of Movement. a. Halts. (1) Short halts made by columns normally are to last 10 minutes and should be taken where possible after every 2 hours
of operation. (2) Long halts made by columns for at least 30 minutes must always be specifically plotted on road movement graphs. (3) The movement control staff can give additional instructions concerning time, duration and/or place of halts. (4) Particular attention is to be paid to the following aspects of traffic discipline during halts:
(a) When making a halt, single vehicles, or vehicles forming part of a column, should move off the roads as much as possible.
(b) If this practice cannot be observed, the commander of a column which is halted must take all necessary measures to facilitate movement of other road users and to avoid accidents or traffic jams. The measures to be taken will vary according to conditions and the width of the road and should include:
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FM 6-50, MCWP 3-1.6.23
i. Warning at sufficient distance from the front and rear of the column (guards, warning flags, lights or flares).
ii. Organizing and directing a system of one-way traffic along the column. b. Overtaking of Columns.
(1) Single vehicles are authorized to overtake columns during their halts or if there is a large speed differential. Vehicles may only overtake if it is safe to do so.
(2) Columns may only be authorized to overtake other columns by the movements control authorities and, if so, the overtaking maneuver has to be supported by traffic regulation personnel.
(3) A column without movement credit may overtake another column in the following circumstances: (a) When the other column is halted and it is safe to do so. (b) When the column commander of the leading column gives clear intention that the following column may overtake and it is safe to do so.
c. Road Movement of Outsized or Heavy Vehicles/Equipment (Special Movement). Special application for the movement of outsize or heavy vehicles must be made before movement credits are granted. National restrictions, above which special application to move must be made, are contained in Annex B.
d. Tactical Situation. (1) On principle, the directions from the local police and from the military police must be obeyed. In times of crisis or in wartime the tactical situation may require a deviation from one or more regulations laid down in this agreement. Such situations may occur for the units in case of immediate danger of enemy threat. (2) In times of crisis or in wartime, night movements will also have to be accomplished without or with restricted lighting (black out lighting) depending on the situation, with due regard to regulations in force to the host nation. It is desirable that a device be incorporated in the vehicle lighting switch, in order to prevent the driver inadvertently switching on driving lights, passing lights or direction indicators while the vehicle is operating under black out conditions.
ANNEX A TO STANAG 2154 (Edition No. 6)
REGULATIONS FOR MILITARY MOTOR VEHICLE MOVEMENT BY ROAD
TERMS AND DEFINITIONS
2. Terms and Definitions used for the purpose of this Agreement. a. Column. A group of vehicles moving under a single commander, over the same route, at the same time in the same direction. b. Organized Element. Marching groups, convoys, packets (STANAG 2155 refers). c. Movement Number. Number, allocated to a movement by the movement control staff responsible for the issue of a movement credit. The movement number should comprise: (1) Two figures indicating the day of the month on which the movement is due to commence. (2) Three or more letters indicating the movement agency issuing the movement credit, the first two letters being the national symbols of the movement agency (see STANAG 1059). (3) Two or three figures indicating the serial number of the movement.
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FM 6-50, MCWP 3-1.6.23

(4) One letter to identify the element of the column (this is optional).

Example below:

15 NLA 41D

d. Special Movement. Road movement of vehicles/equipment with or without load which requires movement credit because of class, dimension or movement restriction based on national requirements.
e. Trail Officer. A subordinate commander in each column who travels at the rear of the column. His duties are to be determined by the column commander. His duties may include: (1) Reporting type and location of dropped-out vehicles. (2) Organizing the safety measures at the rear of the column required at halts. (3) Observing and reporting column discipline.

ANNEX B TO STANAG 2154 (Edition No. 6) REGULATIONS FOR MILITARY MOTOR VEHICLE MOVEMENT BY
ROAD SPECIAL MOVEMENT
All vehicles/equipment exceeding dimensions or qualifications listed below must be considered as special movement and need road movement credit (see Annex C).

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FM 6-50, MCWP 3-1.6.23
Explanatory notes 1. a. Generally in most provinces and designated highways, size limits exceed the limitations quoted;
b. In some provinces certain types of articulated trains are not permitted; c. Weight limitations are based on axle loads, axle spacing and tire size. They vary by provinces and designated
highways. Restrictions on weight may be imposed during spring thaws. 2. For vehicles and trailers with pneumatic tires the permissible axle load and the permissible total width must not
exceed the following values: a. Single axle load
(1) single axles: 10.0 t (2) single axles (live), except for two-axle busses: 10.0 t b. Double axle load, taking into consideration the regulations for the single axle load: (1) axle distance less than 1.00 m: 11.0 t (2) axle distance 1.00 m to less than 1.30 m: 11.0 t (3) axle distance 1.30 m to less than 1.30 m: 16.0 t (4) axle distance more than 1.90 m: 20.0 t c. Triple axle load, taking into consideration the regulation for the single axle load and the double axle load: (1) axle distance 1.30 m or less: 21.0 t (2) axle distance more than 1.30 m to 1.40 m: 24.0 t d. Total weight of individual vehicles, except for semi-trailers, taking into consideration the regulation for axle loads: (1) vehicles with not more than 2 axles:
(a) vehicles: 16 t (b) vehicles with live axle according to point a(2): 17.0 t (c) trailers: 18.0 t (2) vehicles with more than 2 axles: (a) vehicles and trailers: 24.0 t (b) busses which are constructed as articulated vehicles: 28.0 t (c) vehicles with 2 double axles, the centers of which are at least 4.00 m apart: 32.0 t
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FM 6-50, MCWP 3-1.6.23
e. Total weight of vehicle combinations (towing vehicles and semi-trailers) taking into consideration the regulations for axle loads and individual vehicles:
(1) vehicle combinations with less than 4 axles: 27.0 t (2) two-axle vehicle with two-axle trailer or semi-trailer: 35.0 t (3) other vehicle combinations with more than 4 axles: 34.0 t (4) vehicle combinations with more than 4 axles: 40.0 t (5) three-axle vehicle with two- or three axle semi-trailer which transports a 40 foot ISO container in combined freight traffic within the meaning of Directive 73/130/EEC on the determination of common rules for specific transports in combined freight traffic between member nations in the version dated 28 July 1982 (Official EC Bulletin No. L247, page 6): 44.0 t 3. Motor vehicles with one rear-axle: 11 m (IT motor coaches excluded). Motor vehicles with two or more axles: 12 m. 4. 18 m; less if turning radius (a) exceeds 12 m and/or circular crown of turning way (b) is more than 5.30 m.
5. =<50; highways can be considered up to class 120; in peacetime forbidden for tracked vehicles. 6. Vehicles with:
a. 1 axle: 7 m; b. 2 axles: 10 m; c. 3 or more axles: 12 m. 7. Maximum: total weight: 50,000 kg (50 tons); single axle load: 10,000 kg (10 tons); double axle load: 8,000 kg (18 tons);
: 20,000 kg (20 tons), axle distance>2.00 m; triple axle load: 24,000 kg (24 tons). 8. 15 m; for container transporters a maximum length of 15.50 m is allowed. 9. Max. load per single axle: 13 t Max. load per tandem axle: 21 t (Two single axles separated 1.5 m or less are considered a tandem axle) From a separation of 1.35 m down, the maximum limit of 21 t has to be reduced in 700 kg for each decrease of 0.05 m in the distance between the twin axles. Vehicles with two axles, max weight: 20 t Vehicles with three axles, max weight: 26 t Vehicles with more than three axles, max weight: 38 t Combined or articulated vehicles, max weight: 38 t Max load density between farthest axles: 5 t per meter Max pressure to the road: 9 Kg per square centimeter.
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FM 6-50, MCWP 3-1.6.23 10. In UK there is no legal limit applied to the length of a semi-trailer, however, due to the constraints of the
Construct and Use Regulations (UK) which limit the maximum tractor/semi-trailer combination length to 15 m, the semi-trailer-length cannot exceed 12.2 m; in practice this is reduced normally to 12 m. 11. 12 m; for trailers with 4 or more wheels and a distance between the heart of the two outmost rear axles of more than three/fifth of the trailers overall length and provided that own weight of the tractor is 2030 kg or more; otherwise the length of a trailer may not exceed 7 m. 12. 12 m for a motor coach fit up for more than 8 seated passengers which can turn within a circle of 24 m diameter. 13. 4.57 m; for a large motor coach as described at note (12). For motorlorries there is no limit, but certain vehicles over 3.658 m height must carry a notice stating height in-feet and inches in the cab. Bridge heights on secondary roads allow vehicles up to 3.962 m height.
ANNEX C TO STANAG 2154 (Edition 6) REGULATIONS FOR MILITARY MOTOR VEHICLE
MOVEMENT BY ROAD TABLE LISTING THE MINIMUM NUMBER OF VECHICLES FOR WHICH
A MOVEMENT CREDIT IS REQUIRED
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FM 6-50, MCWP 3-1.6.23
ANNEX D TO STANAG 2154 (Edition 6) NATIONAL MARKING OF COLUMNS AND LEGAL RIGHTS
Country BE and DA 1. Flagging
See 6.b. "Minimum lighting and flagging". 2. Lighting
See 6.b. “Minimum lighting and flagging”. 3. Legal rights
None. Country GE
1. Flagging a. Columns consisting of three or more vehicles are to be marked by flags. All vehicles except for the last vehicle display a blue flag. The last vehicle displays a green flag. b. If a column is separated in several independent elements and if the distance between the last vehicle of the following element exceeds the distance ordered between the individual vehicles each element of the column is to be marked by flags according to the provisions for a column.
2. Lighting Also during the day the headlights of all vehicles moving in column must be on.
3. Other provisions In order to warn the following rapid traffic on highways and freeways the last vehicle may display an omnidirectional amber light, or if this light is not available the last vehicle may display operating hazard warning lights instead.
4. Legal rights Closed formations moving in column must leave gaps for the remaining traffic at appropriate intervals. Such traffic must not interrupt the column at any other point. Hence follows that a closed formation or an element thereof is to be considered one road user. That also applies at crossings and junctions. If a part of the formation has already moved into a crossing, the next vehicle must not wait when a vehicle approaches on the road with right-of-way or from the right. It is, however, not justifiable that that right of way is called upon without warning the remaining road users. The warning tasks (no traffic regulation) may be accomplished by military police forces or other military personnel unless police forces regulate the traffic. Military police forces or military personnel detailed for warning must be clearly recognizable as military traffic posts (warning posts), e.g. by brassards or respective clothing. When accomplishing their tasks, military traffic posts are to use the same signals as prescribed for traffic regulation by police forces (STANAG 2025). Other signals to warn road users-where necessary and appropriate-mnust, however, not be excluded. Warning of the other road users must not be accomplished as a traffic regulation function. Only the German Police has traffic regulation authority over civilian road users.
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FM 6-50, MCWP 3-1.6.23
The priority rights of closed formations must not be called upon if: the traffic is regulated in another way by police forces; other road users call upon priority by displaying a blue flashing light together with a signal horn. Such vehicles must always be given free way; a threat to other road users cannot effectively be prevented by traffic regulation by police forces, warning by military police forces of other military personnel detailed for that tasks. That applies especially if the traffic is regulated hy alternating lights, permanent lights (traffic signals) or by the traffic signs "Stop! Give way” or “Give way!". Country GR
1. Flagging a. See 6.b. “Minimum lighting and flagging”; b. The driver of a broken down vehicle must remove the flag and filter (light) and, if technical assistance is required, a yellow flag is to be attached to the vehicle so that it is visible to approaching traffic.
2. Lighting a. The first vehicle of each element must display a blue filter on the front left-hand side headlight or a blue light; b. The last vehicle of each element must display a green filter on the front left-hand side headlight or a green light.
3. Legal rights If part of the column/element, complying to the above stated national requirements, has already moved into a crossing, the next vehicles have right of way. This right should be excercised with necesssary caution. Civilian drivers are not to disturb or obstruct a column.
Country: NL NL requirements for marking of columns in peacetime only: 1. Flagging
a. Two blue flags displayed on the first vehicle of an element mounted on the left- and right-hand front side of the vehicle;
b. One blue flag displayed on each following vehicle of an element, except for the last vehicle, mounted on the right-hand front side of the vehicles.
2. Lighting a. Headlights (low beam) of all vehicles moving in column must be switched on at all times; b. Each vehicle except the last of each element must display a blue filter in the front right-hand side headlight; c. The last vehicle of each element must display a green filter on the front right-hand side headlight.
3. Legal rights If a part of the column/element, complying to the above stated national requirements, has already moved into a crossing, the next vehicles have right of way. This right should be exercised with necessary caution. Civilian drivers are not to disturb or disrupt a column.
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FM 6-50, MCWP 3-1.6.23

1. Flagging

Country: NO

a. See 6.b. “Minimum lighting and flagging”;

b. One sign displayed on the front-side of the first vehicle and one sign displayed on the rear-side of the last vehicle of an element stating "MILITAER KOLDNNE" (black capital characters on a white board).

2. Lighting

See 6.b. "Minimum lighting and flagging".

3. Legal rights

Columns complying to the above stated national requirements have right of way. Civilian drivers are not to disturb or obstruct a column.

Country: SP 1. Flagging
See 6.b. "Minimum lighting and flagging". A red flag must be displayed on vehicles carrying explosives or ammunition, dimensions are not required. 2. Lighting See 6.b. "Minimum lighting and flagging". In order to warn the following rapid traffic on highways and freeways the last vehicle may display an omnidirectional amber light. 3. Other provisions A hazard triangle must be displayed at the front of the first vehicle and at the rear of the last vehicle:

4. Legal rights None. Country: UK
1. Flagging In the UK the national regulations do not recognize column flagging of any sort.
2. Lighting See 6.b. "Minimum lighting and flagging".
3. Legal rights None.
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FM 6-50, MCWP 3-1.6.23

Section VIII
OCCUPYING THE POSITION

2-36. TYPES OF OCCUPATION
This section describes three types of occupation-deliberate, hasty, and emergency. Also, the key functions performed in laying and readying the battery or platoon for firing and for sustaining operations are addressed. Regardless of the type of occupation, local security must be established and maintained. a. A deliberate occupation is one that has been planned. The advance party precedes the unit and prepares the position. The occupation may be during daylight hours following a daylight preparation, at night after a daylight preparation, or at night following a nighttime preparation. A common error in a deliberate occupation is allowing too much activity during preparation, thereby risking compromise. Only the minimum number of vehicles and personnel should go forward. When the tactical situation allows, a very good method of occupying a new position is to do the advance preparation prior to darkness and move by night. Nighttime movement following a nighttime reconnaissance is often necessary, but it can be more time-consuming. b. The hasty occupation differs from the deliberate occupation mainly in the amount of time available for reconnaissance preparation. Generally, it results from unforeseen circumstances. The hasty occupation begins as a deliberate occupation, but due to limited time for advance party preparation of the next position, it becomes a hasty occupation. It reinforces the importance of the battery commander’s planning ahead and establishing priority tasks. c. An emergency occupation results when a call for fire is received while the battery or platoon is conducting a tactical movement.
2-37. DELIBERATE OCCUPATION
a. A guide meets the battery or platoon at the pickup point and leads the vehicles to the entrance of the position area. There the vehicle guides are waiting to lead the vehicles to their selected locations. b. Each gun guide aligns his weapon on the azimuth of fire and gives the initial deflection to the gunner. c. Intrabattery communications are used for laying. d. The GSG implements the security and defense plan as personnel become available. e. Other considerations for night occupations areas follow:

(1) Light discipline must be practiced. Proper preparation for a night occupation will minimize the need for lights. Vehicle blackout drive and blackout marker lights should be turned off as soon as the ground guide has begun to lead the vehicle into position. During the laying process, only the aiming circle (AC) and the weapon being laid should have any night lights on.
(2) Noise discipline is most important, since noise can be heard at much greater distances at night.
(3) The time for occupation is increased. (4) Each vehicle guide should know where his vehicle is in the order of march so the platoon can move smoothly into position without halting the column. (5) Filtered flashlights are used to lead the vehicles.
CAUTION Each driver must stop his vehicle whenever he cannot see the light from the guide’s flashlight.
(6) Vehicles will not move within the position without a guide.
2-38. HASTY OCCUPATION
In a hasty occupation, day or night, the platoon requires more time to occupy. This is because some preparatory tasks were not accomplished due to the limited time available. This may result in the following:
Delay in getting the vehicles off the route of march. Laying by voice. Increased laying time, since gun guides might not have aligned the stakes on the azimuth of fire or obtained initial deflections. Increased FDC preparation time because not all initial updated location data will be available.
2-39. EMERGENCY OCCUPATION
a. General. (1) The nature of the emergency occupation requires
a modification of the normal procedures used to occupy and lay. The procedures apply to all artillery units, towed and self-propelled.

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FM 6-50, MCWP 3-1.6.23

(2) The key to success for the mission is a well-rehearsed SOP.
(3) The XO or platoon leader must know exactly where he is at all times during a road march. He must constantly be selecting possible emergency mission firing positions by map and visual reference. If possible, the BC or gunnery sergeant should identify suitable position areas for emergency missions along the route while performing his reconnaissance and pass this information to the platoon leader or XO. b. Actions Upon Receipt of the Mission.
(1) The XO, platoon leader or FDO receives the call for fire and does the following:
Authenticates the mission. Ensures FDC personnel monitored the call. Notifies the driver. Signals the convoy. Selects a firing position and passes the proposed coordinates to the FDC personnel. Determines the best method to lay the unit. In order of preference, the methods areas follows:
Grid azimuth method. Howitzer backlay method. Aiming point-deflection method. (2) The FDC does the following: Determines the azimuth of fire. Starts computing initial data. See Appendix F for BCS emergency occupation procedures. c. Communications. Data must be passed quickly and efficiently. The small unit transceiver (if available) is an effective tool. Wire can be used if the battery internal wire system is designed for very rapid emplacement. In the absence of these systems or if some elements are not operational, all key personnel must have relays and/or runners in position to get data as they become available. For example, as each nonadjusting howitzer is emplaced, a relay should move immediately to the aiming circle to get his deflection. Another runner should get firing data from the FDC. d. Aiming Points. Aiming points will be established in the following priorities: Distant aiming point (DAP). Collimator.

Aiming posts. e. Security. In M109A3-5 units, for security, the M992 should automatically disperse in a semicircle from the right front around the rear of the position to the left front. They should be well outside the gun line and not be a factor in line of sight between the aiming circle and the howitzer. In towed weapon units where ammunition is carried separately, the prime mover should move to the rear as soon as possible to reduce line-of-sight problems and congestion. Administrative vehicles and their occupants should move into security positions. f. Position Improvement. Upon completion of the mission, the tactical situation dictates whether the unit moves on or continues position improvement, The unit should make the five requirements for accurate predicted tire a priority. (A more detailed discussion of the five requirements is in FM 6-40.) g. Teamwork. There are few tactical activities which require more teamwork than an emergency occupation. Everyone (drivers, gunners, relays, chiefs) must know his job and do it automatically. Remember, engines will be running, and if success depends on a leader shouting commands and directives to untrained personnel, the mission will surely fail.
2-40. SUSTAINING ACTIONS
a. Once the occupation is completed and the unit is ready to answer calls for fire, sustaining actions begin. They are continuous and done in the priority determined by the BC or platoon leader. These actions may include the following:
Improve position defense plans. Improve camouflage. Bury and overhead wire lines. Harden critical elements. Perform maintenance. Rehearse reaction forces. Conduct training. Resupply all classes of supply. Complete position area survey. Be prepared to march-order. Improve the technical solution to meet the five requirements for accurate predicted fire. b. Care must be taken in the way ammunition is resupplied and vehicles are refueled, particularly in SP units. These

2-34

activities can reveal the location of the battery. If possible, these tasks should be done at night. c. The advance party should always be prepared to leave at a moment’s notice.
2-41. TRAINING TIPS
a. During combat, a unit keeps proficient in those skills that are used day-to-day. If not used or practiced, skills that may be required later can be lost. Consideration should be given to conducting training during combat lulls. Such training will ensure that a platoon stays able to perform all skills required. b. Training in convoy operations and immediate action procedures should conform to the unit SOP. This will ensure that personnel are adequately trained to cope with situations that may confront them. Some considerations for establishing a training program are discussed below:
(1) Establish a realistic movement SOP. It should conform to battalion SOPs and should cover, as a minimum, the following:
Approval authority for displacing the battery or platoon. Duties of convoy commanders. Convoy organization. Weapons and ammunition to be carried. Hardening of vehicles. Protective equipment to be worn by personnel. Preparation of vehicles (detailed instructions regarding tarpaulins, windshields, and tailgates). Counterambush action. Drills in reaction to air or artillery attack. Security measures.

FM 6-50, MCWP 3-1.6.23
Maintenance and recovery of disabled vehicles. Any scheduled refueling and/or rest halts. Establishment of rally points. (2) Stress estimating and maintaining the specified interval between vehicles, especially if the column halts. Put interval-marking signs on your motor pool exit to help train drivers. c. Teach the drivers to habitually evaluate the terrain in light of the cross-country mobility of their vehicles. Even in a well-developed area with a good road net, a driver may be required to make an off-road detour to bypass a roadblock or a section of damaged highway. The habit of constant terrain evaluation enables him to make a quick decision and select the most practical route promptly. d. Practice terrain movement in small elements. e. Practice immediate action. Include vehicle breakdowns, equipment transfer, and vehicle repair or recovery. Many such items can be in the SOPs. f. Practice blackout movements to accustom the drivers to using the blackout lights. As they become proficient, restrict them to "cat’s eyes" only. g. Consider the following tips for increasing the units capability for rapid and secure tactical vehicle marches. (1) Do not limit training to those times when the entire unit is available. Whenever two or more vehicles are going to the same place, conduct the movement as a tactical march. (2) Find out how fast the unit can travel, both on and off the road, without losing the slowest vehicles. (Putting the slowest vehicles up front will automatically pace the column.) (3) As a planning guide, on roads and trails the battery or platoon will average 25 kilometers (km) per hour in an open column and 10 km per hour in a close column (at night).

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FM 6-50, MCWP 3-1.6.23
CHAPTER 3
BATTERY DEFENSE
This Chapter implements STANAG 2113, STANAG 2047/ QSTAG 183, and STANAG 2934, Chapter 13/QSTAG 503.

Section I
INTRODUCTION

3-1. THREAT CAPABILITIES
The enemy will direct actions against the field artillery to suppress, neutralize, and/or destroy our capability to fight. All field artillerymen must know and apply passive and active defense measures against artillery, air, and ground attacks if they are to survive and provide continuous and responsive fire support. a. Detection. The enemy will try to detect FA elements. Detection is done through the study of our doctrine and the processing of signals intelligence (SIGINT), imagery intelligence (IMINT), and human intelligence (HUMINT).
(1) Signals Intelligence. (a) Using signal intercept and radio direction finding
(RDF) equipment, the enemy collects various tlequency modulated (FM) and amplitude modulated (AM) transmissions. Through triangulation, the enemy frees the signal. FM monitors are closer to the forward line of own troops (FLOT) because of the limited range of FM radios; AM radio direction finding monitors follow the fmt echelon. About 25 seconds after communications begin, the enemy targeting sequence can continue even if our communications stop. Within 2 to 3 minutes the information can produce a jamming mission, fwe mission, or a combat mission. Tactical FM radios operating on low power can be picked up by enemy RDF units at distances in excess of 10 kilometers. High power signals can be detected at distances up to 40 kilometers. However, directional antennas will improve survivability.
(b) Other targeting means are radars, sound, and visual target detection teams. Radars can detect firing weapons within 100 meters or less. Higher trajectories produce more accurate results. Seismic and sound ranging can produce targets with a target location accuracy of 1 percent of range up to 10 km (error of 100 meters). However, their accuracy is diminished by other battle noise and they are affected by weather and the soil. Unaided

visual observations depend on line of sight and their accuracy varies. Visual, sound, and radar collectors are commonly organic to the front line units; and immediate targeting can be expected. About 10 percent of enemy detection of friendly artillery is by RDF; sound and flash provide about 20 percent and radar and/or visual assets provide the remaining 70 percent.
(2) Imagery Intelligence. This effort is normally coordinated, cued by other sensors. It consists of photographic electro-optical imagery, thermal detection, radar location, and laser imagery. The product from these sensors may require laboratory processing. Data may have to be transcribed to a map sheet during the analysis. The processing of IMINT requires no more than 2 hours. Target location errors from IMINT will be no more than 100 meters.
(3) Human Intelligence. Long range patrols, spies, partisans, and enemy prisoners of war (EPWs) are the HUMINT collectors. Although HUMINT relies primarily on visual observation, the peculiar equipment, predicted activities, bumper markings, spoils of the war, and rubbish that is left behind, add to the accuracy of the targeting effort. b. Attack. A battery can be suppressed and destroyed by the following:
Counterfire. Enemy attacks with up to 600 rounds fired into a 200- x 100-meter area (see FM 100-2-1, page 9-23). Air attack (high-performance aircraft and helicopters). Ground forces (mounted forces of tanks and motorized infantry; dismounted forces of infantry, airborne and/or air assault, and partisans and/or guerrillas). Radio electronic combat (REC). REC combines SIGINT, direction tinding, intensive jamming, deception, and destructive fires to attack enemy organizations and systems.

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FM 6-50, MCWP 3-1.6.23

3-2. BATTERY RESPONSIBILITIES
a. The BC is responsible for general planning, coordination, and execution of his battery defense. The BC analyzes the S2’s IPB and develops an overall defensive plan. On the basis of the tactical situation, the BC must develop his own engagement area based upon avenues of approach, lines of intervisiblity, and the expected threat. The BC must be able to conduct a modified terrain analysis of the position area and surrounding terrain to determine from where the enemy will attack. The BC must graphically portray to his leaders how he intends to defend his position. With this as a beginning, the platoon leader can develop a plan to defend his platoon. He will coordinate with his platoon sergeant for positioning of listening posts (LPs) and/or OPs, fighting positions, direct fire targets, target reference points, or range markers to direct the firepower of the platoon into the engagement area. b. The first sergeant is responsible overall for the execution of battery defense. The first sergeant integrates the platoon defense plans into an overall battery defense plan. This may not be possible due to the distances platoons may be dispersed from each other. If this is the case, the 1SG will review both platoon defensive plans and forward them to battalion. He also will coordinate for resupply all Class IV material and support as necessary.
Note: In a USMC battery, the local security chief is overall responsible for the execution of battery defense.
c. Once the BC’s time line and defensive priorities are established, the platoon leader will coordinate with the platoon sergeant to accomplish the following:
Establish a rally point immediately upon occupation. Develop the platoon defensive plan. Supervise the defense forces.

Direct and sight in the positioning and preparation of the following:
Crew-served weapons. Antitank weapons. Observation posts and/or listening posts. Ensure that communications are installed, checked, and functioning. Designate air TRPs. Select positions for TRPs and range markers. Organize and rehearse the reaction force. Ensure that unit members know equipment and/or material destruction procedures. Ensure that howitzer direct fire targets are established and integrated into overall defensive plan. Ensure that killer junior targets are computed by the FDC and distributed to each howitzer section and that each section chief knows how to compute 10/R. Ensure there is a plan for medical evacuation. d. The section chief does the following: Ensures that the howitzer range card is prepared according to the sectors assigned by the platoon sergeant/1SG. Studies the route to and locations of alternate and supplementary positions. Ensures that the crew-served weapons range cards are prepared in accordance with assigned sectors. Ensures that individual and crew-served fighting positions are properly prepared and have overhead cover. e. All battery leaders must become familiar with the defense plan, rehearse the plan, and brief their subordinates on its execution.

Section II
CONSIDERATIONS FOR DEFENSE

Note: Paragraph F-10 and Appendix H provide further guidance and checklists for battery defense.

3-3. USE OF TERRAIN
a. Camouflage. If it can be seen, it will be hit. If it can be hit, it will be killed. A battery that is concealed or cannot

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FM 6-50, MCWP 3-1.6.23

be recognized has greatly increased its odds for survival. There are six factors of recognition: position, color, shape, shadow, texture, and movement. Following the principles of concealment (camouflage construction, light and noise discipline) helps the battery avoid detection.
(1) Use artificial camouflage. Two artificial camouflage measures that reduce the chance of recognition are pattern painting of equipment with the NATO three-color patterns and proper use of the lightweight screening system.
(2) Properly site electronic equipment to reduce signatures, and position all battery equipment to eliminate exposure and detection.
(3) Make use of all camouflage. Trees and shrubs can hide a battery or platoon. Built-up areas are great for hiding equipment, because man-made items look like other man-made items and do not contrast with natural surroundings.
(4) Use whatever terrain and natural concealment are available to blend into the surroundings.
(5) Maintain light and noise discipline. (6) Use the track plan. The most common signs of military activity in an otherwise well camouflaged area are tracks, spoil, debris, and movement. The BC must enforce his track plan. Existing roads and trails must be used. If none are available, some should be created with heavy vehicles to give the appearance that a unit has moved through the area. The roads and trails must have logical starting and ending points. b. Fortification. (1) Occupy positions that have natural advantages for defense, such as interior tree lines and ravines. (2) Harden battery positions and dig in whenever possible. FM 5-103 shows good examples of hardened positions. (3) Whenever possible, construct obstacles to delay, stop, divert, or canalize an attack force. All obstacles should be covered by fire. Types of man-made obstacles and techniques for their employment are found in FM 5-103. (4) In fast-moving situations, or when emergency displacement is anticipated, hardening might be limited to digging fighting positions on the perimeter, placing sandbags around sensitive equipment such as collimators and tires, and constructing individual shelters for prone personnel. Placing sandbags on or around the engine compartment and the ballistic shield improves survivability of the howitzer. If natural cover is limited or unavailable, individual fighting positions should be constructed. FM 7-7 gives instructions

on how to construct fighting positions, machine gun positions, range cards, and how to establish sectors of fire with crew-served weapons.
(5) Camouflage the spoil from position hardening.
3-4. DEFENSE IN DEPTH
Defensive operations should be planned so that the BC and platoon leaders are warned of an impending attack soon enough to displace the unit or defend the position. Maneuver forces operating in the same area can provide early warning of enemy attacks. The BC should talk to these elements. OPs and LPs are also key elements for early warning. When determining the location of the OPs and/or LPs, consider observation and field of fire, cover and concealment, obstacles, key terrain, avenues of approach, and METT-T. How far from the battery area OPs and LPs are located depends on terrain, visibility, likely threats, and how much time the battery requires to displace or occupy preselected fighting positions. Locate OPs to observe likely avenues of approach so the enemy can be engaged at long range with artillery, mortars, or close air support. Man OPs with at least a two-man team and provide them with antitank weapons, a map, binoculars, night vission goggles, food, water, and two means of communications. OPs must be able to quickly identify target reference points (TRPs) in avenues of approach and communicate to higher. OPs must be briefed on their responsibilities and the enemy situation.
3-5. SECURITY
The cannon battery/platoon is highly vulnerable to attack as it occupies or displaces from a position. The first order of business is establishing security. Due to personnel constraints, a unit may not be able to both fully man an effective defensive perimeter and provide continuous fire support. In accordance with the factors of METT-T, the commander may consider alternatives such as requesting an element from the supported maneuver unit, or “calling out” one of his sections to man the perimeter.
a. Upon occupying a position, each section must have a predetermined sector of responsibility. It must make maximum use of primary weapons and ensure there is a coordinated, all-around defense with interlocking fires. The defense plan includes defensive resources (see Table 3-1, page 3-4) and is visually depicted by a defense diagram (see Section III). The defense diagram is based on the data for each howitzer and each machine gun range card. It includes the fields of fire for grenade launchers, antitank weapons, and individual weapons. The diagram is prepared by the platoon sergeant and approved by the platoon leader. If howitzer sections are dispersed over great distances, the section becomes responsible for its defense. It must be able to defend itself until help arrives.

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FM 6-50, MCWP 3-1.6.23 3-4

FM 6-50, MCWP 3-1.6.23

b. The PSG or platoon leader will assign supplementary positions and ensure that they are depicted on the defense diagram. These positions will reinforce the primary position and allow the unit to perform specific missions such as direct fire. The signal to occupy supplementary positions must be disseminated throughout the unit and the movement to those positions should be rehearsed by the platoon leader and platoon sergeant with all howitzer sections. c. If the platoon is attacked or penetrated by enemy forces, the reaction force will respond by assembling at the predetermined location to:
Assess the situation and deploy to augment the existing perimeter. Deploy using fire and maneuver to expel and/or destroy the enemy. Notify the FDC/BOC of the situation as it develops. Re-establish the perimeter.

d. A suggested composition of the reaction force is as follows:
Reaction force NCO in charge; for example, the platoon sergeant. One man per howitzer section. One man from the fire direction center or POC. One man from the communications section (if available). One man from the maintenance section (if available and in position).
Note: This is only a guide; actual SOP may be different. The battery may also consider making one howitzer section the reaction force. This ensures that there is an NCO in charge and that the force does not have to assemble to be effective; that is, they are already assembled.

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FM 6-50, MCWP 3-1.6.23

3-6. DISPERSION
Dispersion minimizes the effects of an air attack or a counterfire attack. When using this technique, units should disperse, as a minimum, over a 200 by 400 meter area with howitzers no closer than 100 meters apart. The FDC should be positioned approximately 100 meters from either flank howitzer. Figure 3-1 shows a platoon position with elements not dispersed. Figure 3-2 shows a platoon position with elements dispersed. Dotted lines in both figures indicate the area normally covered by enemy counterfire.
Note: With the use of the BCS, and LCU, howitzers can be accurately located over a widely dispersed area of operation. Refer to Chapter 2 for further discussion of weapons dispersion.
3-7. PRIORITIES
a. The BC or platoon leader may be instructed to continue his mission in the position despite hostile counterfire. In that case, he might establish the following tasks in the priority indicated:
Harden critical items of equipment. Prepare individual fighting positions. Prepare defensive positions. Select alternate positions, displacement routes, and a signal in case movement is unavoidable. Brief key personnel on this information. Camouflage. b. The BC or platoon leader may be instructed to displace upon receiving fire. In that case, he would have a different list in mind. For example, he might establish the following tasks to be done before receiving incoming fire: Camouflage. Prepare limited protection for personnel and equipment. Reconnoiter and/or select alternate positions, displacement routes, and march-order signal. Prepare alternate positions.

Prepare defensive positions. Improve individual protection. Improve equipment protection. c. The duties of the section members may be different if they are ordered to continue the mission or displace on receiving fire. Tables 3-2 and 3-3 (page 3-8) are samples of duty breakdowns. Actual work priorities should be included in unit SOPs.
3-8. DEFENSE IN ALL DIRECTIONS
The enemy can attack from any direction; so the platoons must be able to defend in all directions. Based upon METT-T, the unit may consider dispatching patrols to maintain security. Refer to FM 7-8 for specific instructions on the conduct of patrols.
3-9. MUTUAL SUPPORT
Mutual support is one unit helping another unit or one soldier helping another soldier. Battery and/or platoon defensive fire plan targets should be submitted to the battalion FDC and updated as needed. Reports of any type of enemy attack should be forwarded to the battalion as soon as possible after contact is made to use mutual support. Within the platoon, one section must be ready to support another section. Apply the same concept to the individual soldier and you can build a formidable defense. Range cards for crew-served weapons are essential to a good defense. The BC or platoon leader should plan indirect fire targets for the defense of his position. These might include illumination targets if self-illumination is not possible.
3-10. CONTROL
All leaders must control their personnel and firepower before, during, and after an attack so the correct actions can be taken at the right time. Battery leadership should review FM 71-1 for techniques of focusing and controlling fires. Something as simple as what sections will suppress with heavy machine guns, as others direct fire their howitzers, will be difficult to control without rehearsing. The use of range markers out to 1,500 meters or TRPs greatly enhances the effectiveness of massing the fire power in a platoon or battery. Battery and platoon SOPs must be developed and followed to maintain control.

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FM 6-50, MCWP 3-1.6.23
3-11. FLEXIBILITY
No tight will ever go exactly as planned, so the BC and platoon leaders must respond quickly to the unexpected.
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FM 6-50, MCWP 3-1.6.23 They must constantly evaluate METT-T and be prepared to deal with situations that are not in the plan.
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FM 6-50, MCWP 3-1.6.23

Section III
DEFENSE DIAGRAM

3-12. PURPOSE
The defense diagram graphically portrays the position area with respect to the azimuth of fire. The diagram shows the position area, all section positions, all defensive positions (including sectors of fire, TRPs, and adjacent units), and key terrain. It is a key tool to ensure there is a defense plan which can provide 6,400-mil coverage (if necessary) for the battery. Also, this diagram is sent to battalion and is used to develop a battalion defensive fire support plan.
3-13. CONSTRUCTION OF THE DIAGRAM
There are different methods for determining the location of different points for the defensive diagram and constructing the corresponding grid sheet. The LCU or BCS can simplify the process of determining grid coordinates and altitude of positions in and around the platoon or battery area. Computations can be made by using the piece location format. (See ST 6-40-31 or the applicable job aids for the steps.) a. Constructing the Matrix. There are different methods of constructing a matrix on which to draw your diagram. The key is to pick a scale for your casting and northing grid lines which will enable you to plot all or most of the desired locations. The FDC section has preprinted grid sheets which are scaled to 1:25,000, Each grid square represents 1,000 meters on these sheets. Examples of the scale interval you could choose are as follows:
1:12,500–Each grid square represents 500 meters. 1:5,000-Each grid square represents 200 meters (Figure 3-3, page 3-10). b. Constructing the Diagram. The steps to construct a platoon diagram could be as follows: Construct the matrix (Figure 3-4, page 3-11). Add terrain features including dead space. Draw the azimuth of fire to orient the diagram. Plot the required positions (such as howitzers, TRPs, FDC or POC, LPs or OPs, crew-served weapons, tank killer team positions, and Killer Junior targets). Use the grid coordinates obtained from the BCS, LCU, PLGR, or from a map spot.

Draw sectors of fire for howitzers and crew-served weapons (Figure 3-5, page 3-12). Record the related information and grids on the back of the defensive diagram (Figure 3-6, page 3-13). Verify that the defense diagram depicts the BC’s defensive plan and that it graphically portrays the range card data to include TRPs, avenues of approach, and so on. (See Figure 3-6, page 3-13.)
3-14. DISPOSITION OF THE DIAGRAM
Based upon guidance from the BC or 1SG, the GSG begins to construct the defensive diagram during the advance party operations. Once the main body occupies the new position, the GSG gives the platoon sergeant (platoon-based) or 1SG (battery-based) the diagram to be completed or to be checked and verified. If the battery is a platoon-based unit, the 1SG will collect both platoon diagrams and integrate them into the battery defensive diagram. The battery diagram is then sent to the battalion TOC for further consolidation.
3-15. PREPARING RANGE CARDS
a. The platoon sergeant establishes the sectors of fire for the crew-served weapons. When these sectors have been determined and assigned, a range card will be constructed in duplicate, for each primary position. A range card will be partially completed for each alternate and supplementary position. Range cards are continually updated and revised throughout the occupation of the position. Platoon or battery TRPs must be on range cards. This allows the battery leaders the ability to control and mass direct fire assets. The battery leaders must verify the proper construction of all range cards.
(1) Howitzer range card. The DA Form 5699-R (Howitzer Range Card) consist of two parts. A sketch of the sector of fire depicts targets and reference points. A data section lists data necessary to engage targets during periods of limited visibility. Procedures for completing DA Form 5699-R are as follows:
(a) Having been assigned a sector of fire, begin a sketch of the area. Depict left and right limits and potential targets and/or reference points in the SECTORS OF FIRE section. Identify the targets and/or reference points in your sketch by numbering them in order from the most probable to the least probable.

3-9

FM 6-50, MCWP 3-1.6.23 (b) While sighting along the bottom of the bore, direct
the gunner to traverse and the assistant gunner to elevate or depress until the weapon is sighted on the left limit. Direct the gunner to turn the head of the pantel, without moving the tube, onto the collimator (or primary aiming point) and to read the deflection (df) from the reset counter (or azimuth and azimuth micrometer

scales). Record this deflection on the range card in the space marked LEFT DF. If the left limit is also a target, record the deflection in the DF column on the appropriate line for the target number. Direct the assistant gunner to measure the quadrant and record the quadrant. Complete the DESCRIPTION column by annotating a brief description of the target.

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FM 6-50, MCWP 3-1.6.23 3-11

FM 6-50, MCWP 3-1.6.23 3-12

FM 6-50, MCWP 3-1.6.23 3-13

FM 6-50, MCWP 3-1.6.23

(c) Repeat these procedures for the right limit and for all target reference points. Determine the shell, charge, and fuze to be fired for each target and record that information in the appropriate columns. Use the REMARKS column to indicate additional information needed to engage the target; for example, sweep 200.
(d) The measured quadrant and range should be given to the FDC to be converted into a true quadrant. Then record the true quadrant on the range quadrant in the QE column.
(e) When the range card is completed (example in Figure 3-7), make a duplicate card for the platoon sergeant. Continue to update and review the range card throughout occupation of the position.

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(2) Machine gun range card. The machine gun range card consists of two parts: a sketch of the sectors of fire and a data section that list data necessary to engage targets during periods of limited visibility. The sketch depicts the primary and secondary sectors of fire, the location of the weapon, azimuths of the left and right limits and/or the final protective line, target reference points, and any dead space. A sample is shown in Figure 3-8.
Note: A reproducible copy of DA Form 5699-R is at the back of this manual. For additional examples of completed range cards and a reproducible copy of DA Form 5517-R, see FM 7-8.

FM 6-50, MCWP 3-1.6.23

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FM 6-50, MCWP 3-1.6.23

b. Once the range cards are collected by the platoon sergeant, they are used in constructing the sectors of fire on the defense diagram. The result is a completed defense diagram with all pertinent data for the platoon defense (Figure 3-9).

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FM 6-50, MCWP 3-1.6.23

Section IV
CONDUCT OF THE DEFENSE

3-16. DEFENSE AGAINST ENEMY ARMOR/MECHANIZED FORCE
a. If an enemy armor or mechanized force detects the battery or its platoons, the enemy can be expected to take the following actions:
(1) Tanks may assault in an attempt to breach or overrun the firing battery positions.
(2) Threat assault vehicles will maneuver to good standoff fighting positions to fire antitank guided missiles (ATGMs), direct fire cannons, and crew-served machine guns.
(3) These actions will be followed by a hasty mounted or dismounted attack through the battery area. b. The preferred defense against a armor or mechanized ground attack is for the battery or platoon to move to a position from which it can continue the fire support mission (alternate position) without a direct confrontation with the enemy. However, in some circumstances fighting an enemy mechanized force may be unavoidable. Some combat-proven rules for fighting mechanized forces are as follows:
(1) Separate the infantry from the tanks. (2) Slow down the tanks. Use smoke mixed with HE to obscure the enemy’s vision and keep tanks buttoned up. (3) Canalize tanks into predetermined engagement areas by using obstacles and fire support means. (4) Use antitank weapons. (Rehearse tank-killer teams.) Direct fire engagements must be controlled. The unit SOP must address who controls the fires, how to control the fires, and how to mass the direct fire assets. Units may consider self-illumination during periods of limited visibility.
3-17. DEFENSE AGAINST AIR ATTACK
a. The primary way for an FA battery to survive when the enemy has air parity or superiority is to be so well concealed that an enemy cannot detect the battery as a target. If the battery is detected and attacked, the key to survival is dispersion and engaging attacking aircraft with a large volume of fire. Immediate actions against air attack are as follows:
(1) The warning signal for an imminent air attack is given. (See paragraph 3-23).

(2) Every soldier takes cover and prepares to return fire.
(3) All weapons in the battery are used to return fire Accuracy is not as important as mass (see Figure 3-10).
(4) A lead equal to two football fields should be used for fast-moving aircraft. A lead of one-half of a football field is used for slow moving aircraft (helicopters).
(5) Ring-mounted machine guns (.50 caliber) are the only organic air defense weapons in the battery. Primary or supplementary positions selected by the battery should be occupied by vehicles with ring-mounted weapons (M992) to return fire.
(6) Stinger and/or Avenger teams from the division or corps air defense battalion engage enemy aircraft. If available these teams should be positioned to cover primary low-flight avenues of approach into the battery area. Reference points for engaging enemy aircraft should be planned and their location disseminated throughout the unit. These can be terrain features or TRPs established for ground defense. The battalion S2 can aid in determining the likely enemy air avenues of approach for defense planning purposes. The reaction drill to counter an enemy air attack should be rehearsed thoroughly.

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FM 6-50, MCWP 3-1.6.23

(7) Antitank weapons are very effective against low flying rotary-winged aircraft at short ranges. b. Defense of convoys against air attack is as follows:
(1) Move the battery at night, on concealed routes, or during periods of reduced visibility.
(2) Consider infiltration if there is a significant air threat. (3) Post air guards for each vehicle, and assign sectors of responsibility that permit massing small-arms fires. (4) Immediate action against air attack is to disperse vehicles. Everyone must return fire. (5) Designated drivers must have strip maps to the battalion station and alternate medical facilities in the area; rehearse the plan. c. For the employment of the Stinger and/or Avenger teams, see FM 44-18 and FM 44-23-1.
3-18. DEFENSE AGAINST DISMOUNTED ATTACK
a. Dismounted enemy elements will attack by use of the following:
Ambushes. Guerrilla-type attacks (normally not exceeding platoon size and often conducted at night or in adverse weather). A diversionary attack and then a main attack. Dismounted infantry. b. A properly equipped 10-man enemy combat patrol can effectively neutralize a cannon battery that is weak in its defense planning or execution. To keep this from happening, the battery must do the following: Fight the enemy outside the position. Insure fighting positions provide interlocking sectors of fire around the position. Use an overwatch technique. One element will cover the movement of another if defense personnel must withdraw to alternate positions. Chase the enemy with artillery fires when he is beaten back. Do not dispatch forces to chase him. Use mines, barbed wires, and other obstacles. Plan Killer Junior on dismounted avenues of approach.

c. An additional defense against a ground attack (mounted or dismounted) is for the battery or platoon to displace to an alternate position. 3-19. DEFENSE IN OPERATIONS
OTHER THAN WAR (OOTW) The battery could be involved in any number of possible contingency missions, to include OOTW. This is particularly true of artillery units that support light forces. The specifics of battery defense in OOTW depend largely on the situation. Also, they are largely determined by the equipment and offensive capability of the threat. In most situations, the threat consists of paramilitary or guerilla forces with minimum heavy weapons, armor, or air support. The primary ground threat to the battery is dismounted attacks by light infantry or infiltration by sappers or saboteurs. In this situation, the best defensive solution is consolidation of battery elements into a strong defensive perimeter, often called a fire base. For additional information on fire base operations and OOTW, see paragraph F-9 and F-10.
3-20. DEFENSE AGAINST INDIRECT FIRE
Counterfire continues to be the greatest threat facing the artillery. Dispersion, hardening, and movement are techniques used to survive the counterfire threat; but those techniques should not be used in isolation. a. Dispersion is the least expensive method in terms of effort and time. Platoon installations, howitzers, fighting positions, and so forth should be no closer than 50 meters from each other, should not be on line, and should present a deceptively larger element. b. If the ground threat or the terrain makes wide dispersion of the battery or platoon elements impractical, hardening the position will greatly increase survivability. Fighting positions with adequate overhead cover for crew-served weapons and individual soldiers must be prepared and continuously improved. Gun pits for towed howitzers, and hull-defilade positions for self-propelled weapons substantially increase the ability of the unit to survive and continue the mission. c. Unplanned movement to an alternate position denies the maneuver force the amount of FA support it requires; it may increase the number of casualties. The point is, do not move unless your position is untenable.

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FM 6-50, MCWP 3-1.6.23
3-21. DEFENSE AGAINST NBC ATTACK
The BC must ensure that the unit SOPs give procedures for dealing with NBC attacks. SOPs should cover chemical and radiological survey teams, protective measures, immediate action, decontamination, and reporting. Guidance for the commander is provided in FM 3-100.
3-22. EQUIPMENT AND MATERIEL DESTRUCTION PROCEDURES
The BC must ensure that the unit SOPs include the procedures for the destruction of unit equipment and material. He designates personnel to perform the destruction and ensure that adequate emergency destruction (ED) material is available. See DA Pamphlet 25-30, appropriate equipment technical manuals, and STANAG 2113 for guidance in preparing unit SOPs. The applicable details from STANAG 2113 are shown below.
EXTRACT FROM STANAG 2113 (Edition 5) DENIAL OF A UNIT’S MILITARY EQUIPMENT AND SUPPLIES TO AN ENEMY
AGREEMENT 2. Participating nations agree that:
a. An enemy should be denied use of military equipment and supplies of allied forces. b. The denial to the enemy should, if possible, not preclude the later use by allied forces. c. The destruction of military equipment and supplies will only be ordered when their falling into enemy hands cannot
be prevented; food and water may be destroyed or removed, but must not be polluted. d. After commencement of hostilities, in a tactical emergency, and provided that forces have passed to NATO operational
command or control, a NATO commander may order the denial of a unit’s military equipment and supplies. e. The denial of military equipment and supplies to prevent their use by the enemy is the responsibility of the user. f. The provision of instruction and means for, and training in, the denial of military equipment and supplies is a national
responsibility. g. For the purpose of this agreement, the denial will be accomplished by means of destruction, immobilization, removal
ard/or pollution. If possible, when multiple same type weapons systems or equipment are to be destroyed or immobilized, identical components are to be destroyed or removed to prevent re-assembly of the weapon system or equipment by the enemy. DEFINITIONS 3. The following terms and definitions are used for the purpose of this agreement: a. Denial. To prevent the enemy use of a units military equipment and supplies by means of destruction, removal or pollution. b. NATO Commander. A military commander in the NATO chain of command (AAP-6).
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FM 6-50, MCWP 3-1.6.23 c. Unit. Any military element whose structure is prescribed by competent authority, such as a table of organization and equipment; specifically, part of an organization (AAP-6). d. Unit’s Military Equipment and Supplies. This includes unit facilities and installations, civilian equipment and supplies used by allied forces but excludes medical equipment and supplies. e. Pollution (pollute). Destroy the purity of or sanctity of; make foul or filthy; contaminate or defile (man’s environment).
DETAILS OF THE AGREEMENT. 4. Priorities. The priorities and the extent of the denial of military equipment and supplies must be decided by the commander
ordering it, taking into account the their potential value to the enemy. Some examples could be: a. As a high priority:
(1) Classified equipment, materials and documents. (2) Petroleum, oil and lubricants. (3) Sophisticated weapons systems or electronic equipment. (4) Heavy weapons and associated ammunition. (5) Communications equipment. (6) Ferrying and bridging equipment. (7) Air, sea and land transport. b. As a second priority: Any other military stores, military equipments and supplies or military facilities which may be of use to the enemy. 5. Implementation of the Denial. Instructions for the denial of an item of military equipment or of supplies should be included in the appropriate national support publication in sufficient detail to enable their direct use to be denied to an enemy and also to prevent the enemy from making use of them after cannibalization between similar equipments.
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FM 6-50, MCWP 3-1.6.23
3-23. EMERGENCY ALARMS OF HAZARD OR ATTACK
The BC must ensure that emergency alarms of hazard or attack are provided in the unit SOPs. The applicable details to be included in the SOPs have been extracted from STANAG 2047 and are shown below.
EXTRACT STANAG 2047 (Edition 6) EMERGENCY ALARMS OF HAZARD OR ATTACK (NBC AND AIR ATTACK ONLY)
Audible and visual alarm signals must be given by means which cannot easily be confused with other sounds or sights encountered in combat. The alarm signals will be given in all cases as soon as an attack or the presence of a hazard is detected. The alarm signals will be repeated throughout the unit area by all who hear or see the original alarm signal since most available alarm signals are generally limited in range. Additionally, audible and visual alarm signals should normally be supplemented by simultaneous use of radio, telephone, and public address systems. DETAILS OF THE AGREEMENT 3. It is unlikely that personnel can understand and react quickly and correctly to more than two alarm signals. The following hazards require fast and correct reaction: use or presence of chemical or biological agents, and an imminent air attack or nuclear operation. Therefore, alarm signals for these two hazards are mandatory (see Note (1)). In the case of radiological contamination, a delay in personnel taking cover may be acceptable. Note (l): No reference is made to ground attack in order to reduce to a minimum the number of signals. Signals for ground attack, if deemed necessary, remain the prerogative of field commands. 4. The spoken word (vocal alarm signals) remains the most effective means of informing troops in an emergency. 5. Visual alarm signals are included to supplement the audible alarm signals under conditions when audible signals may be lost due to other noises or to replace audible signals when the tactical situation does not permit the use of sound:
a. Reliance should not be placed on visual alarm signals during the hours of darkness or in conditions of poor light.
b. Visual alarm signals should be used when purely audible signals may be lost due to other noise. c. Visual signals should be used to warn those personnel arriving at a particular location of an imminent
hazard. d. Apart from the audio-visual signals detailed at paragraph 2, Note 2 of Annex A, normal signal
flares are excluded from use as a color alarm signal for NBC and air attack. e. Visual signals need not be used by mobile forces. 6. The actual form of a visual signal and method of display are left to the discretion of the local commander. Only the color at Annex A is mandatory. However, to aid recognition, it is recommended that the red signal preferably be square and the black signal preferably be triangular.
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FM 6-50, MCWP 3-1.6.23

7. The alarm signals listed in this agreement are primarily intended to serve as alarms of enemy action. They may be used, however, in an emergency when friendly action could produce similar effects on its own forces. 8. Conflict with civil regulations. Alarm signals for use by NATO forces operating on land are in Annex A. There are some differences between the alarm signals prescribed herein and some national civil defense alarm signals. These differences are considered minor for air attack. Reservations are indicated by each nation where nations or local regulations prohibit NATO Forces operating in their territory for sounding alarm signals in exercises and/or alarm signals incompatible with the public warning system in wartime. 9. Pratice alarm signals. In those case where nations or local regulations preclude sounding alarm signals during exercises, local commanders should negotiate with local authorities to obtain authorization to sound alarm signals periodically. In the absence of agreement, small alarm devices emitting sounds similar to the prescribed audible alarm signals and having limited range should be used during exercises to keep personnel familiar with the audible alarm signals. IMPLENTATION OF THE AGREEMENT 10. This STANAG is implemented when the necessary orders/instructions have been issued, directing forces concerned, to put the content of this agreement into effect.

ANNEX A TO STANAG 2047 (Edition 6) EMERGENCY ALARMS AND WARNING SIGNALS

The following are emergency alarms and warning signs for NATO Forces operating on land. In respect of the audible alarm signal, one or more of the signals listed below should be used.

TYPE OF HAZARD la. Imminent Air Attack.

VISUAL WARNING SIGN 1b. Red. Preferably square in shape.

AUDIBLE ALARM SIGNAL 1c(1) Unbroken warbling siren for one minute. (2) Succession of long blasts on vehicle horns, whistles, bugles or other wind instruments in a ratio of 31; approximately 3 seconds on and 1 second off. (3) Vocal “Air Attack” or corresponding national term where only one nation is involved. TYPE OF HAZARD VISUAL WARNING SIGN AUDIBLE ALARM SIGNAL

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FM 6-50, MCWP 3-1.6.23

TYPE OF HAZARD 2a. Imminent arrival of, or presence of, chemical or biological agents or radiological hazards.
3a. All Clear.
NOTES:

VISUAL WARNING SIGN 2b(1) Black. Preferably triangular in shape. (2) Donning respirators and taking protective action followed by such hand signals as may be prescribed in local instructions. (See Notes 1,2, and 3.)
3b. Removal of appropriate warning signal.

AUDIBLE ALARM SIGNAL 2c(1) Interrupted warbling sound on a siren.
(2) Succession of short signals on vehicle or other horns by beating metal or other objects in a ratio of 1:1; approximately 1 second off. (3) Vocal “Gas, gas, gas” or corresponding national term where only one nation is involved. 3c(1) Vocal “all dear (s-type of attack)” or corresponding national term when only one nation is involved. (2) If used, a steady siren note for one minute or a sustained blast on a vehicle horn, whistle, bugle or other wind instrument to indicate absence of all NBC and air attack hazards.

1. Automatic alarms for the early and rapid detection of biological and chemical agents and radiological hazards may complement the devices referred to previously.

2. A special audio-visual pyrotechnic signal producing a whistle sound and a yellow, red, yellow display of lights may be used. The combination of colors should be produced as near simultaneously as possible.

3. Wearing respiratory protection in the presence of radiological hazards is not mandatory but will be decided by the local commander.

3-24. BOMBING, SHELLING, ROCKETING, MORTARING, AND LOCATION REPORTS
The BC must ensure that his unit SOPs provide guidance concerning bombing, shelling, rocketing, mortaring, and location reports including the format to be used when preparing these reports must also be included. Guidance for the commander is provided in FM 6-121, in Appendix J of this manual, and in STANAG 2934, Chapter 13.

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FM 6-50, MCWP 3-1.6.23
EXTRACT FROM STANAG 2934 (Edition 1) Chapter 13, Annex A FORMAT FOR BOMBING, SHELLING, ROCKETING, MORTARING, AND
LOCATION REPORTS
SECTION I: BOMREP, SHELREP, ROCKREP, MORTREP (indicate which) A. UNIT OF ORIGIN. Use current call sign, address group or code name. B. POSITION OF OBSERVER. Grid reference preferred - encoded if this discloses the location of a headquarters or important observation post. C. DIRECTION (FLASH, SOUND OR GROOVE) AND ANGLE OF FALL/DESCENT (omit for aircraft). Grid bearing of flash, sound or groove of shell (state which) in mils, unless otherwise specified. The angle of fall or descent may be determined by placing a stickhod in the fuze tunnel and measuring in mils, unless otherwise specified, the angle formed by the stick/rod in relation to the horizontal plane. D. TIME FROM. E. TIME TO. F. AREA BOMBED, SHELLED, ROCKETED, OR MORTARED.
1. Location to be sent as: a. Grid reference (clear reference is to be used) OR b. Grid bearing to impact point in mils, unless otherwise specified and distance in meters from observer. This information
must be encoded if paragraph B is encoded (when this method is used, maximum accuracy possible is essential). 2. Dimensions of the area bombed, shelled, rocketed, or mortared to be given by: a. The radius (in meters) OR b. The length and width (in meters)
G. NUMBER AND NATURE OF GUNS, MORTARS, ROCKET LAUNCHERS, AIRCRAFT OR OTHER METHODS OF DELIVERY. H. NATURE OF FIRE. Adjustment, fire for effect, harassing, etc. (may be omitted for aircraft). I. NUMBER, TYPE AND CALIBER (state whether measured or assumed) OF SHELLS, ROCKETS (OR MISSILES), BOMBS, ETC. J. TIME OF FLASH TO BANG (omit for aircraft). K. DAMAGE (encode if required). L. REMARKS. (for additional information on Sections I, II, or III). SECTION II: LOCATION REPORT M. SERIAL NUMBER. Each location which is produced by a locating unit is given a serial number. N. TARGET NUMBER. If the weapon/activity has previously been given a target number, it will be entered in this column by the locating units.
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FM 6-50, MCWP 3-1.6.23

P. POSITION OF TARGET. The grid reference or grid bearing and distance of the located weapon/activity.

Q. ACCURACY. The accuracy to which the weapon/activity has been located. CEP in meters and the means of location if possible.

A: CEP is 50 meters or better.

B: CEP between 50 meters and 100 meters.

C: CEP between 100 and 150 meters.

D: CEP between 150 and 200 meters.

E: CEP between 200 meters and 300 meters, and

I: CEP worse than 300 meters.

R. TIME OF LOCATION. The actual time the location was made.

S. TARGET DESCRIPTION. Including dimensions if possible:

1. Radius of target in meters

OR 2. Target length and width in meters (attitude if possible).

SECTION III: COUNTERFIRE ACTION

T. TIME FIRED. Against enemy target.

U. FIRED BY.

.

V. NUMBER OF ROUNDS-TYPE OF FUZE AND PROJECTILES.

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FM 6-50, MCWP 3-1.6.23

CHAPTER 4
LAYING THE BATTERY, MEASURING, AND REPORTING

Section I
THE AIMING CIRCLE

4-1. DESCRIPTION OF THE AIMING CIRCLE
The M2A2 aiming circle is the primary means of orienting the cannon battery or laying weapons on the azimuth of fire. This section presents information that should be the starting point for any training program on the aiming circle. The aiming circle components are discussed below. a. Telescope. The telescope is a four-power, fixed focus optical instrument with a reticle pattern like the one shown in Figure 4-1.
Note: Some aiming circles may not be equipped with the P-2 reticle pattern (national stock number [NSN] 1240-01-1 52-8516) which is used to perform the POIARIS 2 method of hasty survey. modification can be made at direct support maintenance. Verify the expiration date in the lower right hand corner of the P-2 reticle pattern. If it has expired, turn in the aiming circle to direct support (DS) maintenance for repair.

b. Reflector. The reflector (Figure 4-2, page 4-2) is a plastic signal post mounted on top of the telescope. It is used as an aiming point for other instruments sighting on the aiming circle. c. Elevation Knob. The elevation knob (Figure 4-3, page 4-2) is used to raise and lower the telescope line of sight. It is also used to measure vertical angles. (See paragraph 4-26.)
(1) Elevation scale. Each graduation on the elevation scale (Figure 4-3) represents 100 mils. The scale is numbered at 100-mil intervals. The black numbers 0 to 1100 indicate elevation (+). The red numbers 0 to 400 indicate depression (-).
(2) Elevation micrometer scale. Each graduation on the elevation micrometer scale (Figure 4-3) represents 1 mil. The scale is numbered at 10-mil intervals. The black numbers 0 to 100 indicate elevation (+). The red numbers 0 to 100 indicate depression (-). d. Magnetic Compass. The magnetic compass is located in the main housing (Figure 4-3). For rough centering, the magnetic needle may be seen through the windows on top of the body assembly. A small glass magnifier (Figure 4-3) and reticle with three vertical lines are at one end of the recess. These aid in aligning the end of the magnetic needle. e. Leveling Vials. There are two tubular leveling vials and one circular leveling vial (Figure 4-2) on the aiming circle. One tubular leveling vial (on the left side of the elbow telescope) is used in leveling the telescope so that the operator can measure vertical angles. The other tubular leveling vial (located on the left side of the main housing) or the circular leveling vial (fisheye bubble) is used in leveling the aiming circle for measuring horizontal angles. When the tubular leveling vials are not in use, the protective covers should be closed to prevent damage. f. Azimuth and Azimuth Micrometer Scales.
(1) The azimuth scale (Figure 4-3) is located below the magnetic compass housing. It is graduated in 100-mil increments from 0 to 6,400 mils and is numbered every 200 mils. The portion of the azimuth scale from 3,200 mils through 6,400 mils has a second 0-3200 scale numbered in red from the black 32 through the large black 0 on the azimuth scale.

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FM 6-50, MCWP 3-1.6.23

Note: Also located on the azimuth scale is an imaginary line called the 0-3200 line. This line starts at the black O and goes through the black 32 on this scale. This is the line we orient on the azimuth of fire during the laying process.
(2) On the azimuth scale, the red numbers 0 to 3200 indicate azimuth. The lower row of graduations parallels the 3,200- to 6,400-mil upper row of graduations. This permits the aiming circle to be used with other instruments that have scales labeled from 0 to 3,200 mils. The red numbers are used only in the following instances:
(a) You are reading red numbers to an M12-series sight, and you are measuring a deflection.
(b) You are checking the lay of one aiming circle with a second circle. The operator of only one of the two circles will see red. He can read red to preclude having to add or subtract 3200 to or from the reading.
(3) The azimuth micrometer (Figure 4-3) is located on the azimuth knob on the lower right side of the magnetic needle housing. It is graduated in 1-mil increments from 0 to 100 mils and is numbered every 10 mils. Azimuth micrometer can be read to an accuracy of 0.5 mils. g. Upper (Recording) Motion.The upper motion allows the operator to place values on the azimuth scale and azimuth micrometer by means of the azimuth knob (Figure 4-3). The values are read on the azimuth scale index, which is located below the magnetic needle magnifier. The upper motion of the instrument has both a fast motion and a slow motion. Pulling back on the azimuth knob enables fast motion. Rotation of the azimuth knob produces slow motion. Horizontal angles are read in two parts--the thousands and hundreds of mils are read from the azimuth scale, and the tens and units of mils are read from the azimuth micrometer. h. Lower (Nonrecording) Motion. The lower motion is controlled by the orienting knobs (Figure 4-2). It is used to orient the 0-3200 line of the aiming circle without changing the values on the upper motion. Lateral movement of one orienting knob enables fast movement of the lower motion of the aiming circle. The two orienting knobs should be used at the same time for slow movement of the lower motion. Caps are provided for covering the orienting knobs to prevent unintentional use of the lower motion. i. Leveling Screws. The three leveling screws (Figures 4-2 and 4-3) are used to level the aiming circle. These screws are on a spring plate located below the orienting knobs and above the baseplate assembly.

j. Base Plate Assembly. The base plate assembly (Figure 4-3) serves as the base of the instrument when it is mounted on the tripod and also serves as the base of the carrying case. It is a flat circular plate to which the instrument is attached by means of the spring plate. An instrument-fixing screw is threaded into a socket on the underside of the base plate assembly to attach the instrument to the tripod. The socket is kept clean and free of obstructions by a spring-loaded cover that remains closed when the instrument is not attached to the tripod. The base plate is fitted with a rubber gasket

4-2

that forms a watertight seal when the cover is latched to the baseplate. k. Notation Pad. A rectangular notation pad (Figure 4-2) on the baseplate is used for recording the declination constant, date of declination, and initials of the person performing the declination. l. Filter. The filter (Figure 4-3) is a lens, which is placed over the eyepiece for protection against the sun’s rays. It is stored on the side of the telescope body. It is held in place by a spring-loaded ball. m. Compass Needle Locking Lever. When the locking lever (Figure 4-2) is in a vertical position, the needle is locked. When the lever is turned either right or left to the horizontal position, the needle is unlocked. To preclude damage to the magnetic needle, this lever should be returned to the locked position gently.
CAUTION The needle must be locked when not in use.
4-2. SETTING UP THE AIMING CIRCLE
a. To setup the aiming circle (Figure 4-4), do the following actions:

FM 6-50, MCWP 3-1.6.23
(1) Unstrap the legs of the tripod, loosen the leg clamp thumbscrews, and extend the legs to the desired length. Tighten the leg clamp thumbscrews.
(2) Place the tripod over the point to be occupied. One tripod leg should be pointing in the approximate direction of sighting, and the leg with the night-light mount should be to the operator’s left. Attach the plumb bob to the hook under the instrument-fixing screw assembly. The plumb bob should be within a l-inch radius of the station marker.
(3) Firmly embed the tripod legs. Make sure the tripod head is approximately level when the legs are embedded. Then remove the tripod head cover.
(4) Pull back the spring-loaded cover on the base of the baseplate and place the aiming circle on the tripod. Loosely screw the instrument-fixing screw assembly into the base plate.
(5) Center the plumb bob over the orienting station by moving the base plate of the aiming circle.
(6) Tighten the instrument-fixing screw into the baseplate of the aiming circle.
CAUTION Be careful not to exert excessive pressure when you are tightening the instrument-fixing screw. The slotted arm may bend and damage the tripod head.
(7) Remove the aiming circle head cover, and hang it on the tripod head cover or a leg clamp thumbscrew to prevent damage.
(8) Install the night lighting device accessory case if necessary. b. Some common malpractice are as follows:
Not clearing the area of magnetic attractions such as weapons, steel helmets, and eyeglasses. Failure to set up the tripod so that one leg points in the direction of the sighting. This puts one more tripod leg in the instrument operator’s way as he moves around and increases the chance that he will kick a leg and knock the aiming circle off level.

4-3. LEVELING THE AIMING CIRCLE
There are two methods of leveling the aiming circle for normal use. Either the circular leveling vial or the tubular leveling vial (Figure 4-5) can be used.
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FM 6-50, MCWP 3-1.6.23
a. The preferred method is to level the aiming circle by using the circular leveling vial (fisheye bubble) as follows:
(1) Loosen the leveling screws approximately halfway. (2) Rotate the head of the aiming circle until the circular leveling vial is over the leveling screw adjacent to the notation pad. (3) Using the thumb and forefinger of each hand, turn the other two leveling screws in opposite directions. The bubble will move in the same direction as the left thumb. Note: This is known as the left thumb rule. (4) When the bubble moves on line with the fisheye, center the bubble by using only the third leveling screw. Rotate the head over each of the other two screws. If more than half the bubble moves out of the center ring, relevel the instrument. If the bubble cannot be centered, use the technique discussed in b below. Then turn the instrument in for repair as soon as possible. b. Level the aiming circle by using the tubular leveling vial as follows: (1) Loosen the three leveling screws (approximately halfway) to permit the instrument to be leveled. Rotate the instrument until the axis of the tubular leveling vial is parallel to any two of the three leveling screws. Center the bubble by using these two leveling screws. Grasp a screw between the thumb and forefinger of each hand. Turn the screws simultaneously so that your thumbs move either toward each other or away from each other. This movement tightens one screw as it loosens the other. The bubble always moves in the same direction as the left thumb. (2) Rotate the instrument 1,600 mils, and center the bubble by turning the third leveling screw.

(3) Rotate the instrument back to the first position, and relevel the bubble if necessary.
(4) Repeat these steps until the bubble remains centered in both positions.
(5) Rotate the instrument 3,200 mils from the first position. If the bubble remains centered in this position, rotate the instrument 3,200 mils from the second position. If the bubble remains centered in this position, rotate the instrument throughout 6,400 mils. If the bubble remains centered, the instrument is level. If the bubble does not remain centered when the instrument is rotated 3,200 mils from the first position, the leveling vial is out of adjustment. To compensate, using the same leveling screws that were used to place the instrument in the first position, move the bubble halfway back to the center of the leveling vial. Rotate the instrument 3,200 mils from the second position; and using the other leveling screw, move the bubble halfway back to the center of the level vial. The instrument is now level, and the bubble should come to rest in its vial at the same off-center position (within one graduation) regardless of the direction in which the instrument is pointed. If the leveling vial is out of adjustment, the instrument should be turned in for repair at the first opportunity.
(6) The plumb bob normally remains attached to the aiming circle until the firing unit is laid.
4-4. TAKING DOWN THE AIMING CIRCLE
Take down the aiming circle as follows: a. Elevate the telescope to about 300 mils. b. Ensure that the magnetic needle is locked. c. Cover the tubular leveling vials. Be sure the M51 instrument light is turned off and secured in its case. d. Ensure the caps of the orienting knobs are closed. e. Place the azimuth knob over the notation pad. f. Turn the leveling screws counterclockwise until the screws are to their lower stops. Then loosen each leveling screw knob one-quarter turn. g. Place the carrying case cover over the aiming circle, and latch the cover locks. h. Unscrew the instrument-fixing screw, and remove the instrument from the tripod. i. Replace the tripod head cover. j. Retract and collapse the tripod legs, and tighten the thumbscrews. k. Strap the tripod legs together.

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4-5. DECLINATING THE AIMING CIRCLE
a. The aiming circle must be declinated when any of the following situations exist:
After an electrical storm. Anytime the instrument has received a severe shock; for example, if it is dropped from the bed of a truck to the ground. The magnetic needle is a delicately balanced mechanism, and any shock may cause a significant change in the declination constant. Anytime the aiming circle is moved outside a 25-mile radius from the area in which it was last declinated. Because of local magnetic attractions, any move of the aiming circle may result in an appreciable change in the relationship of grid north and magnetic north as measured by the instrument. A minimum of once every 30 days to determine if any changes in the declination have occurred because of the annual shift of magnetic north or because of accidents involving the instrument that may not have been reported. If a radical change is observed, the instrument should be declinated again within a few days to determine if the observed change is a real change in the characteristics of the instrument. When the instrument is first received. Anytime the instrument is returned from ordnance repair. b. The aiming circle must be declinated in an area free from magnetic attractions. Azimuths must be known to two or more azimuth marks, preferably in opposite directions. These azimuth marks should be a minimum distance of 300 meters, preferably 1,000 meters. c. Declinate the aiming circle as follows: (1) Set up the aiming circle, and level it. (2) With the upper (recording) motion, set the known azimuth to the azimuth marker. (3) With the lower nonrecording motion, sight on the azimuth marker that corresponds to the azimuth set with the upper motion. (See Figure 4-6.)

FM 6-50, MCWP 3-1.6.23
(4) Release the magnetic needle. With the upper motion, float and center the magnetic needle. (See Figure 4-7, page 4-6.)
(5) Read the declination constant directly from the azimuth scales (to the nearest 0.5 mil).
(6) Using a second azimuth, repeat the above steps. (If a second azimuth marker is not available, use the first marker again.)
(7) Compare the two declination constants determined. If they agree within 2 mils, determine the mean. Express it to the nearest whole mil by using artillery expression. On the notation pad, record the mean (four-digit number), the date, and the initials of the individual performing the declination.

Note: At this time, the 0-3200 line will be aligned with grid north.

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FM 6-50, MCWP 3-1.6.23

Note: If the two values differ by more than 2 mils, repeat the entire process.
d. A declination station maybe established by simultaneous observation, hasty astro, observation of Polaris, or circumpolar observation. (See Chapter 5.) e. Declination can be performed by scaling a grid azimuth to two distant points. The following procedures are used:
(1) Place the aiming circle over the selected point and level it.
(2) Select two distant points on a map. Scale the direction to each from the occupied point.
(3) Using the direction scaled from the map, declinate the aiming circle by the procedures previously discussed.
(4) Compare the two values determined. They must agree within 10 mils.
(5) If the values determined agree within 10 mils, determine the mean; record it on the notation pad. If the values do not agree within 10 mils, repeat the entire procedure.

Note: A declination constant determined by simultaneous observation or from a map should be verified as soon as possible.
4-6. CARE AND HANDLING OF THE AIMING CIRCLE
a. Protect the aiming circle from shock. b. Keep the instrument clean and dry. c. Clean the lens with an optical lens cleaning brush and lens tissue only. d. Keep the magnetic needle locked anytime it is not in use. e. Keep the aiming circle head cover over the aiming circle head. f. Cover all tubular leveling vials. g. Rotate the azimuth knob until it is over the notation pad before trying to replace the head cover.

Section II
PRECISION LIGHTWEIGHT GPS RECEIVER (PLGR)

4-7. GLOBAL POSITIONING SYSTEM DESCRIPTION
Global positioning system (GPS) is a space-based navigation system which provides worldwide, continuous, all weather, three-dimensional position information. The GPS system consists of the following three primary components:
The satellite constellation. Ensures worldwide coverage with a minimum of four satellites within electronic line of sight to any point on the earth. A master control station and five monitoring stations. These provide ground-based support for the satellites. The GPS receivers. These receivers provide the operator with navigational and location data. Currently, the primary receiver being issued to ground forces is the AN/PSN-11, precision lightweight GPS receiver (PLGR). The PLGR can provide location information precise enough for use by cannon artillery. For detailed

information on the GPS/PLGR operation, maintenance, and additional equipment, refer to TM 11-5825-291-13. Major components of the PLGR are shown in Figure 4-8.
4-8. FA SURVEY APPLICATIONS
The PLGR can be used to determine the grid location of the orienting station. Individual howitzer locations can also be determined, but individual PLGR-derived positions are not on common survey control. The following actions must be taken to ensure accuracy when using the PLGR as an artillery positioning device: a. Verify PLGR Setup.
(1) Crypto. The proper crypto keys must be loaded before the PLGR will function using the precise positioning system (PPS). The PPS must be used to achieve the necessary accuracy and to avoid enemy electronic warfare measures. If the crypto variable is not loaded, the PLGR cannot be used to establish artillery positions.

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FM 6-60, MCWP 3-1.6.23

(2) Datum. Map datum should be the same as the operational datum being used by all other maneuver, fire support and target acquisition units. If the same datum is not used, significant position errors are possible.
(3) Coordinates. The UTM coordinate format is preferred since it is the standard used by survey and most fire control systems.

(4) Elevation. Mean sea level is the preferred selection since most military maps use it as the basis for the elevation scale.
(5) Units of measurement. Meters is the preferred selection since most military maps refer to distance and elevation in meters.
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FM 6-50, MCWP 3-1.6.23

(6) Almanac data. Almanac data must be 1 day old. If almanac data are not 1 day old, there are possible satellite vehicle or timing errors not noted by the PLGR. b. Figure of Merit (FOM). FOM is an accuracy estimation of the data displayed by the PLGR which ranges from one through nine. FOM 1 is the best accuracy estimation displayed by the system, and FOM 9 is the worst. For artillery positioning, only coordinates determined with a FOM 1 will be considered for use. c. Mode of Operation. The PLGR offers the choices of FIX, CONTINUOUS, or AVERAGING as modes of operation. The AVERAGING mode yields the most accurate data and is preferred when determining a position for indirect fire weapons. d. Verify Position. Position verification, to check for unacceptable errors, must always be done prior to firing. The following are possible methods of verifying a PLGRderived grid coordinate:
(1) Always use two persons to check the PLGR data. (2) Use two different PLGRs to independently determine the position data. (3) Use resection or graphic resection if identifiable points are visible. (4) Conduct a map spot of the location. A map spot is the minimum acceptable verification and should be used in conjunction with the other available means.
WARNING Azimuth determined with the PLGR is for navigation only The PLGR azimuth is not accurate enough for use in establishing directional control and should never be used for that purpose. Tests show that the PLGR-determined azimuth maybe in error by as much as 200 mils.

4-9. GPS LIMITATIONS AND CONSIDERATIONS
a. GPS receivers rely on electronic line of sight with the satellites. The PLGR must be able to acquire at least four satellites before a three dimensional position can be determined. Dense foliage, buildings, mountains, and canyons will mask GPS signal and cause the receiver to fail. All GPS receivers automatically try to track satellites to a position as low as 10° above the level horizon. Each receiver has a function which displays the direction and vertical angle to each of the satellites being tracked. Use this display to determine if signal masking is what is causing the system to fail. When a satellite signal is masked, the operator can either reorient the PLGR antenna or move to another location to improve signal reception.
b. Multipath distortion (reflected signals) may occur if the receivers antenna is tilted away from a satellite. This causes a reflected signal to be received which has more power than the direct signal. Coordinates determined under these conditions can be off by as much as several hundred meters. To correct this problem, reorient the receiver antenna to a position that eliminates the distortion.
c. As with all aspects of artillery operations, personnel must be properly trained in the safe operation of equipment. The PLGR will provide accurate location data only if it is operated in strict accordance with the procedures outlined in the technical manual. Battalions and batteries must ensure that training and testing on GPS operations are part of their safety certification program. Specifically, all battery level leadership must be able to identify, and properly correct when needed, the setup functions of the PLGR. These personnel must also be proficient in map reading and hasty survey techniques needed to conduct an independent verification check of the PLGR-derived position.

SECTION III
GUN LAYING AND POSITIONING SYSTEM

4-10. DESCRIPTION OF THE GUN LAYING AND POSITIONING SYSTEM
The gun laying and positioning system (GLPS) supplements the M2A2 aiming circle, and will be the primary instrument used to orient howitzers in cannon units not equiped with Paladins. When used in conjunction with the PLGR, the GLPS will determine grid location, establish directional

control, and allow the operator to transfer directional control to the individual howitzers using standard laying commands. Additionally, the GLPS eye-safe laser range finder eliminates the need to measure subtense to determine the distance to the howitzer. The system is man-portable and tripod-mounted. It can be emplaced and used much the same as the M2A2 aiming

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circle, but without the need for external survey support. Technical data on GLPS capabilities are located in Table 4-1, and the major components of the system are shown in Figure 4-9. Battery leadership must be proficient in the setup and orientation procedures for the GLPS as listed in the equipment operator’s manual. An independent check of the GLPS orientation must be made before using it to lay the howitzers.

FM 6-50, MCWP 3-1.6.23

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FM 6-50, MCWP 3-1.6.23

Section IV
THE M2 COMPASS

4-11. DESCRIPTION OF THE M2 COMPASS
The M2 compass (Figure 4-10) is the alternate instrument for orienting, or laying cannons. The unmounted magnetic compass is a multipurpose instrument used to obtain angle of site and azimuth readings. The components of the M2 compass are discussed below. a. Azimuth Scale. The azimuth scale is numbered every 200 mils from 0 to 6400. The scale is graduated every 20 mils and can be read to an accuracy of 10 mils. b. Sights. The compass has front and rear leaf sights and a mirror in the cover for sighting and reading angles. c. Levels. The compass is equipped with a circular level for leveling the instrument before the azimuth values are read. A tubular level is used with the elevation scale to measure angles of site. d. Angle-of-Site Mechanism. Rotation of the level lever causes the elevation level and the elevation scale index to rotate as a unit. The index clamps against the bottom piece to keep the mechanism from moving unless it is actuated by the level lever. e. Magnetic Needle and Lifting Mechanism. The magnetic needle (the white end of the needle) shows a magnetic north direction for orienting purposes. The needle is delicately balanced and jewel-mounted, on a pivot, to rotate freely. The magnetic needle reading is taken when the bubble is centered in the circular level. The lifting

mechanism includes a needle-lifting (locking) pin and a needle lifting lever. The lower end of the pin engages the lever. The upper end projects slightly above the body of the compass to engage the cover when it is closed. Thus, it automatically lifts the needle from its pivot and holds it firmly against the glass window. f. Azimuth Scale Adjuster Assembly. The azimuth scale adjuster assembly rotates the azimuth scale to introduce the declination constant. Two teeth at the adjuster engage teeth on the underside of the azimuth scale. Thus, turning the adjuster with a screwdriver rotates the azimuth scale approximately 1,800 mils. The scale is read against a fixed index under the rear sight hinge.
4-12. DECLINATING THE M2 COMPASS
a. The procedure for declinating the M2 compass from a surveyed declination station free from magnetic attractions is as follows:
(1) Set the M2 compass on an aiming circle tripod over the orienting station, and center the circular level.
(2) Sight in on the known, surveyed azimuth marker. (3) Using the azimuth adjuster scale, rotate the azimuth scale until it indicates the same as the known surveyed azimuth. (4) Recheck sight picture and azimuth to the known point. Once the sight picture is correct, and the azimuth reading is the same as the surveyed data, the M2 is declinated.

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b. The procedure for field-expedient declination of the M2 compass is as follows:
(1) Using the azimuth adjuster scale, set off the grid-magnetic (G-M) angle (shown on the bottom of all military maps).
(2) Once the G-M angle has been set off on the azimuth scale, the M2 compass is declinated.
4-13. MEASURING AN AZIMUTH AND SITE TO CREST WITH THE M2 COMPASS
a. The procedure to measure an azimuth follows: To read the azimuth scale by reflection, hold the compass in both hands at eye level with arms braced against body and with the rear sight nearest your eyes. Place the cover at an angle of approximately 45° to the face of the compass (Figure 4-11) so that the scale reflection can be viewed in the mirror. Level the instrument by viewing the circular level in the mirror. Sight on the desired object and read the azimuth indicated on the reflected azimuth scale by the south-seeking (black) end of the compass needle.

b. The procedure to measure site to crest follows: Hold the compass on edge with both hands at eye level with arms braced against the body and with the rear sight nearest your eyes. Place the cover at approximately 45° to the face of the compass (Figure 4-11) so that the elevation scale reflection can be seen in the mirror. Sight on the crest of the highest object in the sector of fire. Center the elevation scale tubular level with the lever on the back of the compass and by viewing the elevation scale in the mirror. Read the elevation in mils on the elevation scale. Measure the sight to crest two additional times, and record the average.
CAUTION When measuring an azimuth be sure no magnetic materials are near the compass.
4-14. CARE AND HANDLING OF THE M2 COMPASS
The M2 compass will not stand rough handling or abuse. Keep the compass in the carrying case (with the mirror side facing in) protected from dust and moisture.

Section V
LAYING

4-15. PRINCIPLES OF LAYING
a. Reciprocal laying is a procedure by which the 0-3200 line of one instrument and the 0-3200 line of another instrument are laid parallel. To fully understand the principle behind reciprocal laying (Figure 4-12, page 4-12) you must first understand several concepts and definitions.

(1) As was mentioned previously, the aiming circle is the primary means by which the cannon battery orients weapons on the azimuth of fire. The aiming circle is used to measure horizontal clockwise angles from the line of fire to the line of sight to a given aiming point. In reciprocal laying, the aiming point for the aiming circle is the howitzer panoramic telescope. The pantel is used to measure

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FM 6-50, MCWP 3-1.6.23
horizontal clockwise angles from the line of fire or the rearward extension of the line of fire to the line of sight to a given aiming point. In reciprocal laying, the aiming point for the howitzer pantel is the aiming circle.
(2) The line of fire, as it relates to the principle of reciprocal laying, is any line parallel to the azimuth of fire. It is first established by the aiming circle in order that the aiming circle can be used to orient the howitzer on the azimuth of fire.
(3) The rearward extension of the line of tire is the exact opposite of the line of fire.
(4) A deflection is defined as a horizontal clockwise angle measured from the line of fire or the rearward extension line of fire to the line of sight of a given aiming point with the vertex of the angle at the pantel. That is to say, the angular measurements taken when reciprocally laying with the aiming circle and the howitzer pantel will always be deflections. b. The principle of reciprocal laying is based on the following geometric theorem: given two lines cut by a common transversal whose alternate interior angles are equal, then those two lines are said to be parallel. The parallel lines are the 0-3200 lines of the aiming circle and the line of fire and rearward extension of the line of tire of the howitzer. The common transversal is the line of sight established between the aiming circle and the pantel. The

alternate interior angles are the deflections as read from the instruments.
4-16. PROCEDURES FOR LAYING
a. When the 0-3200 line of the aiming circle is parallel to the azimuth of fire, the instrument operator uses the upper motion to sight on the lens of the pantel and reads the deflection on the azimuth and azimuth micrometer scales. He announces the deflection to the gunner on the howitzer.
Note: If the weapons are equipped with M12-series deflection cannot exceed 3,200 mils. Therefore the red numbers on the aiming circle are used if the black numbers exceed 3,200 mils. b. The gunner sets the announced deflection on the pantel. He orders the howitzer to be shifted, and/or traverses the tube, until the line of sight through the pantel is again on the reflector of the aiming circle (2-step deflection method). Note: Because the pantel is not directly over the pivot point of the tube, the pantel displaces horizontally. When the telescope has been sighted on the aiming circle, the gunner reports READY FOR RECHECK.

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