Chapter V
Naval Gunfire

Section		Page
I.	Mission	111
II.	Classification of batteries and ships	116
III.	Basic organization	122
IV.	Coordination of naval gunfire	125
V.	Techniques	131
VI.	Naval gunfire annex	134
VII.	Illustrative problem	134

Section I
Mission

Par.
501.	Naval gunfire mission	111
502.	Characteristics of defensive positions	111
503.	Relative importance of targets	113
504.	Classification of fires	113
505.	Definitions	113
50.6	Shore fires required in amphibious operations	114

501. Naval gunfire mission.--In amphibious operations, it is the mission of certain naval task groups to replace the landing force artillery in supporting the assaulting troops by fire on shore targets. That is, by delivering fire on enemy personnel, weapons, and other defensive installations, and on critical terrain features which may conceal undiscovered enemy positions, ship batteries enable the landing force first to land, then to advance, hold, or withdraw, with fewer casualties than would otherwise be possible. In some cases, effective naval gunfire may be the critical factor which determines success or failure.

502. Characteristics of defensive positions.--

     1. The exact nature of the fires required in the fulfillment of the above missions depends on the character of the defense against which the amphibious attack is launched. In the absence of definite information to the contrary, it must always be assumed that the assault will be met by an organized defense, and a suitable fire plan must be executed based on this assumption with probable targets located by a study of the terrain.

     2. The defense of an area on which a beachhead is to be established will comprise naval, air, and ground forces. All of these defenses must be engaged and rendered ineffective prior to and during the assault to an extent that will permit the establishment of the landing force ashore. Naval gunfire will have an obvious role in the engagement of air and naval defense forces, but provision must be made for these actions, separate from the fire power allotted to the engagement of the ground defense with which this chapter is concerned.

     3. The character of the defense which will be met in any one instance will depend on:

        1. The terrain.
        2. The tactical doctrine of the enemy.
        3. The size, composition, and morale of the enemy force.

        All of these factors must be carefully considered on the basis of available information, and the gunfire plan fitted to the estimate of each situation.

     4. However, regardless of terrain, enemy doctrine, and the local enemy force, the ground defense may be considered in the following categories:

        1. The beach defenses.
        2. Tactical defense areas inland (strong points).
        3. Artillery.
        4. Observation and command posts, communication nets, supply areas.
        5. Reserves.

        The naval gunfire plan must contemplate the engagement of all these defensive components at the proper time. (See fig. 1 "Phases of D-day" par. 506 below.)

5. Beach Defenses.--This term is taken to include both passive and active weapons, which are installed on or in the immediate vicinity of the landing area, and the troops which man the weapons. Passive weapons are such installations as land mines, barbed wire, and other obstacles. The active weapons are principally machine guns and light, rapid-fire artillery pieces, emplaced to deliver direct fire on the beaches and the immediate sea approaches. The number of these weapons and the size of the forces manning them will vary with each situation, and their actual locations will rarely be definitely known in advance. But in all cases heavy fire must be maintained on their known or probable positions during the approach of the assault landing waves to the beach.

6. Strongpoints.--The terrain inland from the beach will contain a varying number of localities which lend themselves to defensive organization (hills, ridges, stream lines, villages, etc.). These localities are also normally the critical areas which the landing force must seize to secure the beachhead. These strongpoints may or may not be occupied by enemy troops and if occupied the strength of the defensive unit may vary from a squad to a battalion. However, those strongpoints immediately in rear and to the flanks of the landing beaches must be engaged by fire prior to the landing of the assault waves and fire power must be immediately available to engage these strongpoints, and others further inland, when it is found necessary by the attacking troops.

7. Artillery.--Any active defense of an area suitable for landing operations will normally be supported by both field artillery and coast artillery batteries.

   1. The coast artillery normally has a mission to deny the use of the sea approaches. These batteries are permanent installations and must be rendered ineffective before or during the debarkation period. If there is any likelihood of a coast battery being still in firing condition on D-day, its engagement must be planned for by the assignment of one of the largest naval batteries available to this task.

   2. Field artillery is mobile and can move rapidly from place to place in the accomplishment of its mission to place fire on the attacking troops. The location of field artillery batteries will rarely be known prior to the attack, but from a study of the terrain, positions suitable for batteries can be determined and fires should be planned for these areas. Naval gunfire must be prepared to place fire immediately on field artillery batteries discovered in position whether or not they are actually firing.

8. Observation and command posts, communication nets, supply areas.--These are secondary targets and they should be engaged only if definitely located and if ammunition is available above the requirements of more immediately important targets.

   1. The defense depends on ground as well as air observers for vital information as to the nature, strength, and point of attack in order that troops may be alerted and disposed to meet the attack, and in order that mortar and field artillery fire may be adjusted on the attackers. These observation posts will normally be on high ground both in the beach area and further inland, usually within the perimeter of a strongpoint. Naval gunfire may blind the enemy during the debarkation and beach assault periods by engagement of areas containing these observation posts.

   2. The commanders of defending units will establish command posts in small areas centrally located with respect to the various defensive installations. These command posts are normally in defilade and under cover from air observation and consequently will rarely be definitely located. If, however, their positions are known, fire may be placed on the areas in order to disrupt the execution of the defensive plan.

   3. The defense depends on its communications (wire, radio, roads) for transmission of information, orders, troops and supplies. Fires should be planned for critical points in the communication net in order that they may be delivered on call if schedule fires on these points are not practicable. The critical points are the command posts (since in their vicinity are usually located switchboards and radio sets), and road junctions, bridges, fords, and other restricted points in the road system whose destruction or blocking will impede the mobility of the defenders.

   4. Supplies represented by ammunition dumps, oil storage areas, truck parks, etc., are remunerative targets for naval gunfire if located. They will normally be of easy access to roads or trails, and in the absence of suitable personnel or weapon targets probable supply dump areas should be engaged.

9. Reserves.--Regardless of the number of troops committed to the defense by occupation of the beach positions and of the strongpoints immediately in rear of the beaches, a good proportion of the defense forces will normally be held in reserve in centrally located areas. Bivouac

areas of these units should be engaged early in the naval gunfire plan and provision must always be made to bring heavy fire to bear immediately on these reserves moving up to meet the attack.
10. Figure 11 (see sec. VII) indicates a possible organization for defense by the trace of targets. But it must be clearly understood that definite information on targets will be meager prior to the attack, that enemy tactics and doctrine will vary. In the absence of specific information the principle must be followed of placing fire at the proper times in all areas from which, should he be there, the enemy could defeat the attack.
503. Relative Importance of Targets.--The relative importance of the targets which naval gunfire must engage will vary according to the stage of the attack. During the debarkation period (phase I, in par. 506 below), active coast batteries are the most important, with known beach defenses and other definitely located troops next in order. During the ship to shore movement of assault boat waves, the beach defense areas and the strongpoint areas commanding the beaches are the priority targets. These areas must be covered completely during this period (phase II in par. 506 below). Fire must also be maintained on any coast batteries still active and on active field artillery batteries. If any ship batteries remain unemployed, and if the ammunition supply permits, other targets of importance which should be engaged during this phase are definitely located enemy reserves and rear area strongpoints known to be occupied. During the period of the attack inland (phase III in par. 506 below) most of the targets will be designated by personnel ashore with the landing force. Any target so designated should take precedence over targets designated by other means. Of targets designated by the landing force (or by air observers), a counterattack is of primary importance, with enemy weapons such as artillery, mortars or machine guns next.

504. Classification of fires.--The fires executed in the general performance of the naval gunfire mission may be classified as follows:

     1. Effect sought:

        1. Neutralization.
        2. Destruction.

     2. Form:

        1. Concentrations.
        2. Point fires.

     3. Prearrangement:

        1. Fires delivered on time schedule.
        2. Fires delivered on call.
        3. Fires on targets of opportunity.

     4. Tactical purpose:

        1. Preparation.
        2. Close support.
        3. Deep support.
        4. Special missions.

     5. Method of fire control:

        1. Direct fire.
        2. Indirect fire.

505. Definitions.--

     1. Effect sought.--

        1. Neutralization.--Neutralization fire is area fire delivered for the purpose of causing severe losses, hampering or interrupting movement or action and, in general, to destroy the combat efficiency of enemy personnel. In the usual case, neutralization is only temporary and the target becomes active soon after fire ceases. Neutralization is accomplished by short bursts of fire of great density to secure the advantage and effect of shock and surprise. Most targets engaged by naval gunfire will be of the type for which neutralization is appropriate.

        2. Destruction--The term is applied to fire delivered for the express purpose of destruction and when it is reasonable to expect that relatively complete destruction can be attained. Destruction should be attempted only under favorable conditions of target designation and observation.

     2. Form.--

        1. Concentrations.--A concentration is a volume of fire placed on an area within a limited time. It is the form used for neutralization. The term is applicable regardless of the tactical purpose of the fire. Concentrations may be plotted in the form of numbered circles with the principal part of the target at the center of the circle.

        2. Point fires.--Point fire is fire directed at a definite material target to destroy that particular object. Point fires may also be plotted by a numbered circle, usually of smaller size than those used for plotting concentrations.

3. Prearrangement.--

   1. Fires delivered on time schedule.--Some schedule fires can be definitely planned in advance, both as to time and as to place. A time schedule is made for the purpose of coordinating these fires with the movement of the assault boat waves or with the advance of attacking troops on shore. This schedule may be in tabular or graphic form. The time will normally be shown as so many minutes before or after (minus or plus) H-hour, in order that the actual clock time of execution of these fires may be changed by simply changing the time of H-hour. This principle of flexibility is especially applicable to the preparation. The time schedule fires in this Phase must conform closely to the actual movement of the assault boat waves at each beach. See Section IV for discussion of the necessary coordination.

   2. Fires delivered on call.--These are fires which are planned in advance as to location but which are delivered only upon request. They are plotted in the form of numbered concentrations for ease in designating them when required.

   3. Fires on targets on opportunity.--Targets of opportunity are targets which appear to the observer and which have not been plotted for execution on time schedule or on call. Observers may designate these targets to the firing ships by reference to a plotted concentration, by coordinates from a grid system standardized for the operation, or by other means (see par. 531).

4. Tactical purpose.--

   1. Preparation.--This term is used to designate intensive fire delivered on the landing beaches and adjacent areas during the approach to the beach of the landing craft of the leading wave.

   2. Close support.--This term designates those fires furnished in support of units ashore. It is fire placed on enemy troops, weapons, or positions which, because of their proximity, present the most immediate and serious threat to the supported unit.

   3. Deep support.--This term includes the more distant fires furnished in support of the operation as a whole as distinguished from those of direct and immediate benefit to front line troops. Characteristic applications are fires placed on enemy artillery, on enemy reserves, and on critical points or areas which it is desired to prevent the enemy from using.

   4. Special missions.--These may be considered as a type of deep supporting fire for which large caliber naval guns are particularly suitable, such as long range fire on cities, airfields and seacoast batteries, and the destruction of heavy permanent fortifications.

5. Method of fire control.--

   1. Direct fire.--Direct fires are fires delivered on targets which can be seen from the firing ship. Spotting of the fall of shot is normally carried out from the ship.

   2. Indirect fire.--Indirect fires are fires delivered on targets which cannot be seen from the ship. These fires are spotted by plane spotters or by spotters on shore.
506. Shore fires required in amphibious operations.--

     1. The fire support requirements of the infantry in an amphibious operation are essentially the same as the requirements in normal land warfare. The over-all requirement may include fires executed in advance of D-day, such as bombardments for the destruction of enemy supplies and raids to confuse him as to the point of attack. The requirement may extend for some period of time beyond D-day in support of operations seeking to expand the beach head. If such is the case, plans must be made to effect re-supply of ammunition.

     2. This chapter is primarily concerned with the requirements of D-day. For the purpose of planning naval gunfire support, it is convenient to divide D-day into three phases as illustrated in figure 1.

FIRES REQUIRED DURING PHASES OF D-DAY

Phase duration	Landing force activity	Required fires	Targets	Spotting agency
I. H-3 hrs. To H-1 hrs. (approx.)	Debarkation; Boat waves form.	Deep Support; Special Missions.	Coast batteries. Major beach defenses, other definitely located installations, and troops.	Air, Ship.
II. H-1 hr. (approx) to H hr.	Ship to Shore (assault units).	Preparations; Deep Support; Special Missions.	Preparation on landing beaches. Coast batteries still active. Active field artillery batteries. Any other targets of special importance.	Ship, Air.
III. H hr. To _____.*	Assault units are advancing inland from beach. Shore Fire Control Parties begin operations ashore. Reserve elements are landing.	Close Support; Deep Support.	Counterattacks. Strong points. Active field artillery batteries. Other targets called for by SFCP and air observers.	Shore Fire Control Parties, Air, Ship.
* In phases I and II, field artillery support is entirely lacking. At about H plus 2 hours field artillery can being to take over some of the fires, but it will be rare in landings against opposition that artillery will be able entirely to relieve naval fire support groups during D-day.

Figure 1.

Section II
Classification of Batteries and Ships

Par.
507.	Characteristics of naval gunfire	116
508.	Ammunition classified	118
509.	Guns classified	118
510.	Batteries classified	118
511.	Ships classified	120

507. Characteristics of naval gunfire.--The suitability of naval gunfire for the support of shore operations is fixed principally by:

     Characteristics of the ammunition.

     Weight of metal.
     Weight of high explosive.
     Type of fuze.

     Characteristics of the guns.

     Caliber and rate of fire.
     Muzzle velocity and elevation.
     Pattern.

     Characteristics of the batteries.

     Number of guns in the battery.
     The type of fire control installation.

     Characteristics of the ships.

     Draft, speed, and maneuverability.
     Magazine capacity.
     Availability of air spot.
     Number of types of batteries available.

     1. Characteristics of ammunition.--

        1. The ratio, weight of metal to weight of high explosive, generally fixes the type of fragmentation obtained. When the ratio is small, good fragmentation is obtained and the fragments are effective at greater distances. This is the type of shell used against personnel. When the ratio is large, the fragments produced are few and are effective over an area of smaller radius. This is the type of shell used against material since its heavy walls enable it to defeat the walls of the object hit and introduce the high explosive inside of the object.

        2. Fuzes provided for each of the two general types of projectiles are designed, for the first type, to detonate the explosive charge above the ground (time fuze) or on the surface of the ground (superquick fuze); and for the second type, to detonate the charge after penetration of varying depths depending on the amount of delay introduced into the fuze.

        3. Types of ammunition other than high explosive have obvious special uses, such as smoke shell for blinding hostile observation and star shells for illumination of the target area at night.

     2. Characteristics of guns.--

        1. In general, the caliber and rate of fire determine the type of target for which a gun is best suited. As the caliber (size) of a gun increases the range usually is increased and the rate of fire decreases. Large caliber, slow firing guns are best used against fixed material targets or large critical areas; smaller, rapid-fire guns are suited for the engagement of personnel targets as well as for use against light material, either fixed or mobile.

        2. The muzzle velocity and elevation of a particular gun determine its usefulness in the engagement of targets on reverse slopes or in otherwise defiladed areas. Guns with high muzzle velocity and low maximum elevation are in general restricted to fires on targets on forward slopes or targets at some distance beyond the mask. If a high velocity gun can be elevated up to approximately 45° practically any shore target can be engaged since the resultant angle of fall is sufficiently steep to reach targets in normal defilade. If the guns can be elevated to, and range tables are provided for, elevations above 45°, the ability to search reverse slopes is correspondingly increased. Considerable latitude in the selection of firing areas must be provided if defiladed targets at greatly differing ranges must be engaged by the same battery. Reduced charges furnished with H.C. projectiles lower the normal high velocity of naval guns and permit defiladed targets to be engaged at shorter ranges. The use of firing areas to a flank will sometimes permit targets to be engaged by guns which otherwise would be unable to reach them, since the mask is thus avoided.

        3. The pattern of a gun is the characteristic which principally determines its use in relation to friendly troops. The smaller guns usually have the smaller patterns and this enables

them to place fire close to friendly troops without unduly endangering them from "shorts." A pattern of 300 yards or less is highly desirable for these close support guns since fire should be maintained on the enemy up to the last possible second in order that the interval between the lifting of fire and the actual assault of the enemy position may be as short as possible. Since the deflection pattern is much less than the range pattern, firing areas which permit the use of fire across the front, rather than over the head, of attacking troops are extremely desirable.
3. Characteristics of batteries.--The term "battery" as used in matters pertaining to support of the landing force is defined in paragraph 510 below. So defined, the number of guns responding to one control and bearing on one target is the naval gunfire support battery.

   1. The number of guns in the battery determines the type of fire mission it can best fulfill. For personnel targets (neutralization) a minimum of four guns to a battery is desirable in order to produce the necessary volume of fire quickly and to cover the total target area simultaneously. Batteries with fewer than four guns should not be assigned normal close or deep support missions except in an emergency. More than 6 guns per battery will usually (for the smaller calibers) only result in an unnecessary expenditure of ammunition. For material targets to be destroyed, adjustment is facilitated if the number of guns is kept to one, two, or three (not more than one turret). For large areas, special mission targets, involving both material and personnel, such as airfields, cities, large supply dumps, docks, etc., where fine adjustment is not required, more guns per battery are desirable.

   2. The type of fire control installation provided for each battery will determine whether or not the battery is restricted to targets which can be engaged by direct fire or whether it can efficiently furnish fire spotted by air or shore observers. Batteries furnishing fires in close support must have the most modern type of fire control installations capable of executing fires without the use of aiming points, unless the close support fires are furnished units advancing along the shore by ships moving parallel with the supported troops and firing across their front on generally visible target areas.

   3. With the very modern installations and navigational instruments, unobserved fires on large areas are practicable; but should never be used if the target area is close to friendly troops.

4. Characteristics of ships.--

   1. The draft, speed, and maneuverability of a ship determines how close to the shore and how close to enemy shore battery positions the ship can take station in carrying out its fire-support missions. Relatively shallow draft, high speed, quick-turning ships are suited for engagement at close range of targets in the vicinity of the beach, both to cover the landing of the assault waves of the landing force by preparation fires, and to cover the heavier, less maneuverable ships by engagement of coastal batteries.

   2. The magazine capacity of a ship determines the probable duration of its employment. As a general guide it may be stated that 50 percent of the total magazine capacity of fire-support ships will be made available for shore-target ammunition. Of this 50 percent, at least one-half must be reserved for targets of opportunity in phase III by close and deep-support ships. Assignment as a close-support ship of a battalion or deep-support ship of a regiment should not ordinarily be made unless the magazine capacity of the ship assigned is such that suitable ammunition sufficient to engage at least 15 targets of opportunity is available during phase III. In the event several destroyers act as a group in close support the combined magazine capacity of the group should provide this supply of shore-target ammunition.

   3. Unless airspot with suitable communication is available, a ship is not very effective as a deep support ship since the majority of targets which it must engage will not be visible either to ship or shore spotters.

   4. The number and type of fire-support batteries determines which landing force echelons a ship can support. A ship with only one battery can effectively support only one unit (either close support of a battalion or deep support of a higher echelon); while a ship with two or more batteries may, depending on the estimated strength of the enemy defense, furnish effective close support to a battalion with one or two batteries and deep support to the regiment of which the battalion is a part with another battery. The same ship, however, should not normally be assigned in close support of battalions of different regiments, nor should it be assigned in deep support of one regiment and in close support of a battalion of another regiment, since the effective support of widely separated units will not normally be practicable due to the difficulties of providing a suitable firing position, and of affording effective liaison and communications.

508. Ammunition classified.--Naval projectiles, according to their characteristics, are classified with respect to their relative effectiveness for neutralization as follows:

     Antiaircraft (air burst).
     High capacity (superquick fuze).
     Antiaircraft (impact burst).
     High capacity (short delay fuze).
     Common.
     Armor piercing.

     Their relative effectiveness for destruction of fortifications with direct hits is in inverse order.

509. Guns classified.--The characteristics of the principle types of naval guns classify them as follows:

     1. Close support.--Five-inch naval guns possess the necessary high rate of fire and small pattern to fit them for close support missions. They will normally have sufficient range to answer all calls for fire on D-day. Suitable angle of fall is provided for most situations.

     2. Deep support.--The 6" and the 5"/38 caliber guns possess the requisite range, rate of fire and the small pattern to make them excellent weapons for deep support of landing force echelons up to and including the division. The 6" gun is especially suited for counterbattery against all types of enemy field artillery in range of the landing areas.

     3. Special missions.--The larger caliber guns (8" and above) possess rates of fire too slow and their patterns are too large to make them excellent close support weapons. These large caliber guns are classified tactically as deep support weapons employed on special missions against long range targets as cities, airfields, and major fortifications, and for the destruction of heavy, permanent fortifications. The 8" guns, in the event that 6" guns are not available, can be utilized in long range counterbattery.

     4. Preparation.--All guns are suitable for participation in the preparation, the 5-inch on the beach and the larger calibers on adjacent areas, or the heavy calibers in the early part and the lighter calibers in the latter part of the phase.

510. Batteries classified.--For the purpose of planning and executing naval gunfire in support of a landing, a naval battery is defined as two or more guns of the same caliber on the same ship which can be controlled from the same station. The gun and fire-control installations on modern ships provide a high degree of flexibility in the performance of fire missions. Thus, some cruisers can bring to bear on a single target with equal ease and speed, from two to fourteen 5-inch guns; or from three to fifteen 6-inch guns. A modern light cruiser (Cleveland class) can engage effectively a maximum of two targets with 5-inch batteries and two targets with 6-inch batteries simultaneously. The standard naval batteries employed in rendering naval gunfire support are listed in figure 2 and their normal tactical classification is shown. The number of guns in a battery will vary slightly according to the exact nature of the ship.

STANDARD NAVAL GUNFIRE SUPPORT BATTERIES

No. cal.	Classification	Maximum effective range	Standard target area yards (Note 1)	Fire required for effect for neutralization (Note 2)		Targets per hour (Note 3)	Ammunition expenditure per hour (Note 3)
				Rds.	Min.
4 5"/25	Close support	12,500	200x200	80	2	6	540
4 5"/38	Close support Deep support	16,000	200x200	80	2	6	540
6 6"/47	Close support Deep support	23,000	300x300	60	2	6	420
9 8"/55	Deep support Special mission	27,000	400x400	54	3	6	384
Larger caliber batteries are normally reserved for special missions and for neutralization of large areas in deep support.
Notes.--(1) Standard target areas are based on size of normal pattern of guns by caliber as follows: 5"/25 and 5"/38 150 yards. 6"/47 250 yards. 8"/55 400 yards. (2) The given number of rounds delivered in the areas listed in the time allotted is considered sufficient to establish neutralization of those areas. Therefore, the size of the standard battery is fixed by the number of guns which will deliver the required number of rounds in the set time. A comparison of the standard batteries with comparable field artillery battalions in neutralization capacity is given by the computation below; however, actual experience in shore bombardment also indicates that the above table presents a satisfactory picture of the neutralization capacity of naval batteries.

Naval shell	Weight		FA shell	Weight		Rds. delivered 1 min.		Total weights delivered
								Stand. Nav. Bty.		FA Bn.
	Metal, lbs.	HE		Metal, lbs.	HE	Stand. Nav. Bty.	FA Bn. (12 guns)	Metal	HE	Metal	HE
5" AA	46	7	105 mm. HE	26	5	40	48	1840	280	1248	240
6" HC	92	13	155 mm. HE	77	16	30	36	2760	390	2772	576
8" HC	239	21	8" HE	170	30	18	12	4302	378	2040	360
(3) Number of targets and ammunition expenditure per hour include 10 ranging shots for adjustment on each target and an average time of 7 or 8 minutes per target for turns and ranging salvos.

Figure 2.

511. Ships classified.--The principal types of naval gunfire ships are destroyers, light cruisers, heavy cruisers, and battleships. According to their characteristics, the ships, themselves, are classified as follows:

     1. Destroyers.--The shallow draft, high speed, and good maneuverability of destroyers fit them particularly for the preparation in phase II. They can stand close inshore, ahead of and to the flanks of the boat waves, and place accurate direct fire on beach area targets at close ranges. They are excellent for the delivery of close supporting fires in phase III, particularly in support of units attacking along the shoreline, and should be used for this purpose to the limit of their ammunition supply. The small total number of targets which one destroyer can engage prevents the normal assignment of one such ship as a close fire support group.

     2. Cruisers.--These are equally close support and deep support ships. The availability of airplane spot, adequate radio communication facilities and control systems enable them to engage targets over a wide front, the 5-inch batteries in close support and the main batteries in deep support. The greater suitability of the 6-inch guns for engaging normal land targets as compared to the 8-inch guns makes the light cruiser preferable to the heavy cruiser. The magazine capacity of the cruisers enables them to take part in the preparation with both their 5-inch and main batteries, if necessary, and still to carry out the deep and close support missions.

     3. Battleships.--These must be generally classified as deep support ships, particularly suited for participating in the preparation and for the execution of special missions beyond the power of the other ships. If, however, hydrographic conditions permit, and there is no danger of the battleship being caught in restricted waters, these ships are ideal for furnishing close supporting fires with their 5-inch batteries. Figure 3 summarizes the fire support characteristics and capacity of the principal types of naval ships.

Section III
Basic Organization

Par.
512.	Fire support requirements	122
513.	The fire support group	122
514.	Observation	123
515.	Communications	123
516.	Liaison	123
517.	The shore fire control party	123
518.	Basic organization for D-day	123
519.	Training and technique	125

512. Fire support requirements.--Figure 4, paragraph 518, outlines the fire support requirements from an organizational point of view. The requirements for fire support must be met for organizational reasons as well as for reasons of fire power, before success can be reasonably expected. Below are listed the basic requirements from standpoint of firepower.

     1. Requirements in batteries.--

        1. Phase I.--Sufficient batteries to establish and maintain neutralization on known and suspected enemy guns capable of reaching the transport area.

           Sufficient batteries to neutralize enemy observation, to disrupt his communications and to neutralize his field artillery positions, bivouac areas, outposts and other forward garrisons.

        2. Phase II.--Sufficient batteries to neutralize all beach defenses.

           Sufficient batteries to continue engagement of coast batteries.

           Sufficient batteries to engage field artillery batteries which can fire on beach areas.

           Sufficient batteries to furnish deep support to each assault regiment and each division.

     2. Requirements in ammunition.--Sufficient ammunition of suitable types to engage each target on time schedule twice with an equal amount reserved for targets of opportunity. (The average requirement in ammunition per target is shown in fig. 3, par. 511; this matter is further discussed in par. 522.)

     3. Requirements in ships.--Sufficient ships to provide the necessary batteries and ammunition, including sufficient numbers of the following type:

        Sufficient highly mobile ships (destroyer or equivalent) to cover the movement of the assault landing waves close in to the beach.

        Sufficient cruisers to furnish close support to battalions and deep support to regiments and divisions.

        Sufficient battleships (or heavy cruisers) to meet the special mission requirements.

     4. Bearing in mind that the requirements must be met both from the standpoint of organization as well as from the standpoint of fire power, it may be stated that the amphibious assault of a beach head protected by a "normal" defense can be adequately supported on D-day by the assignment to the support of each assault regiment of:
        4-8 destroyers,
        2 light cruisers, and
        1 heavy cruiser (or battleship),
        with one additional heavy cruiser or battleship per Landing Force division.

513. The Fire Support Group.--

     1. The fire support group is the basic unit for the delivery of fires. They are classified as close fire support groups, deep fire support groups, and special fire support groups. The close fire support groups are assigned on the basis of one per assault infantry battalion of the landing force. The deep fire support groups are assigned on the basis of one per assault infantry regiment, and one additional per division if required. The special fire support groups are assigned as necessary, principally for the preparation and for special targets. The composition of each fire support group is dependent on the estimate of the enemy strength in each landing area (the probable number of targets which must be engaged), and the hydrography of the fire support areas, as well as on simplicity of fire control. By reason of simplicity of communication and fire control it is desirable that only one ship constitute a fire support group whenever practicable. It may sometimes be necessary and desirable to constitute both a close fire support group and a deep fire support group from the same ship (but see par. 507d (4)).

     2. The light cruiser is the ideal component of the close fire support group. The 6-inch light cruiser and the heavy cruiser are preferable as components of deep fire support groups for the regiment. The battleship is best reserved for deep support of the division and for use as a special fire support group. The use of destroyers as special fire support groups for participation

in the preparation and for the purpose of firing on targets of opportunity on the flanks of the area to be attacked using ship spot is highly desirable. It may be desirable at times to use several destroyers instead of one cruiser as a close fire support group. When a close fire support group is so constituted, the destroyers will normally rotate in answering calls from shore fire control parties.
514. Observation.--While the effective delivery of unobserved fires is theoretically practicable, naval gunfire must normally be observed and adjusted for the desired effect (large area targets are exceptions). Observers are used stationed either on the firing ship, on another ship, in an airplane, or with front-line elements of the landing force.

     1. Ship observers.--In phases I and II, practically all fires delivered in areas visible from seaward will be controlled by the normal ship spotters. Spotters may be placed on control vessels to obtain a better view of the beach and adjacent areas.

     2. Air observers.--Air observers are used primarily to control the deep support batteries of cruisers and battleships in the execution of long range fires. Normally, the ship concerned will supply the plane. The spotter may be a specially trained artillery officer of the landing force. The above arrangement reduces the chances of misunderstandings to a minimum.

     3. Observers with the landing force.--Once the attack has left the immediate beach areas, fires in close support of the front line units must be called for and adjusted by observers with those units. Shore Fire Control Parties are organized for this purpose. Their functions are discussed in detail in paragraph 517 below.

515. Communications.--Each observer is provided with a primary fire control channel of communication direct to his firing ship, and arrangements are made as far as practicable to supply an alternate means in the event the primary means becomes inoperative. For the observers on the firing ships, the ship's communication system is used; if the spotter is stationed on the control vessel, a portable radio set is used as the primary means with the ship's visual signalling apparatus as the alternate. The airplane radio set is the primary means employed by the air spotter working directly with the ship's radio on an assigned frequency. The communications provided the Shore fire Control Parties are discussed in paragraph 517 below.

516. Liaison.--Two types of liaison are required: Liaison from the fire-support group to the supported infantry commander, and liaison from the landing-force units to the firing ships. Normally, one naval gunfire liaison officer is sent from each fire support group to the supported commander. He should be well qualified in naval gunnery in general, and have complete information on the characteristics of the ships that compose the group and their armament; his information must also include knowledge of the fire support areas assigned. The naval gunfire liaison officer must be provided with radio equipment operating on the same frequency as the shore fire control party with whom he is associated. The radio equipment and radio personnel are furnished by the landing force.

     A minimum of one landing force liaison officer is normally provided for each fire-support group. If a fire-support group contains more than one cruiser or battleship, a liaison officer from the landing force should be furnished each ship. The landing force liaison officer must have a complete knowledge of the proposed scheme of maneuver and of the enemy situation (as shown in the intelligence annex and subsequent reports).

517. The Shore Fire Control Party.--One Shore Fire Control Party is organized for each assault battalion of the landing force, and is attached directly to the staff of the battalion commander. Each party consists of:
     1 officer--spotter.
     1 noncommissioned officer--assistant.
     1 private--instrument operator.
     Communication personnel as required.

     Acting under instructions of the battalion commander, the party occupies the best observation post available, moves as necessary, establishes and maintains communication with the fire support group assigned, and engages targets designated by the battalion commander, or targets of opportunity in accordance with the instructions of the battalion commander. The assistant, as well as the officer, should be capable of adjusting fires. Communication between the battalion command post and the Shore Fire Control Party is maintained by the battalion. In the event the party's radio equipment becomes inoperative, an alternate means of communication with the fire support group is thus provided by way of the naval gunfire liaison officer at the battalion command post. The personnel and equipment of the Shore Fire Control Parties will be furnished by the artillery component of the landing force.

518. Basic Organization for D-day.--Figure 4 illustrates the basic principles of organization for the delivery of naval gunfire support on D-day.

Basic Organization for Naval Gunfire Support On D-Day

Figure 4.

519. Training and Technique.--It is incumbent on a commander of a Naval Attack Force to assure himself that all units of his force have been trained and exercised in landing operations, including the delivery of naval gunfire on shore targets in which the fire-support groups, designated to support assault units on D-day, will have executed fire missions controlled by the Shore Fire Control Parties and air spotters with whom they will work on D-day. The technique employed in the delivery of fires should be carefully prescribed and practiced. See section V for a discussion of various techniques.

Section IV
Coordination of Naval Gunfire With Other Elements of the Attack Force

Par.
520.	Elements with which coordinated	125
521.	Means of effecting coordination	125
522.	Maps	125
523.	Fire support areas	126
524.	Firing runs	126
525.	Target areas	130
526.	Time schedules	130
527.	Liaison officers	130
528.	Observers	130
529.	Special signals	131

520. Elements with which coordinated.--Coordination is a responsibility and function of command. The orders for the operation must clearly provide for the coordination of naval gunfire in all its aspects with the following elements and activities:

     1. With the transports and transport debarkation areas.

     2. With the boat lanes to the landing beaches and with the movement of the assault wave to its beach.

     3. With the scheme of maneuver of the landing force and with the actual maneuver of the landing force units.

     4. With the activities of combat aviation.

     5. With the landing force artillery.

521. Means of effecting coordination.--To effect the coordination of naval gunfire with these other elements and activities the principal means used are listed below and discussed in succeeding paragraphs.

     1. By prescribing a map, chart, or photograph, suitably gridded as the fire-control map for the operation.

     2. By the assignment of fire-support areas to fire-support groups.

     3. By scheduling various types of firing runs.

     4. By assigning target areas of responsibility to the fire-support groups.

     5. By prescribing a time schedule for the execution of certain fires.

     6. By effecting an exchange of liaison officers between fire-support groups and other units.

     7. By placing gunfire observers with the landing force and in the air.

     8. By prescribing special signals for use in connection with naval gunfire.

522. Maps.--

     1. A map of suitable size and scale is prepared from the best available data (air photos, hydrographic charts, reconnaissance reports, etc.) and is furnished firing ships, shore fire control parties, air observers, liaison officers, and any others directly concerned with naval gunfire. The standard grid system prescribed for the operation is superimposed on this map, in order that locations of targets from other sources such as infantry front line commanders may be readily plotted on the fire-control map. The map must include sufficient sea area and sufficient shore line data to permit its use in designating the fire-support areas and in plotting the firing runs of the ships. The time schedule and on-call targets are indicated on the map by appropriate numbered circles.

     2. There are several different grid systems which may be used. The standard M-square grid system (see CSP 734) is the one most commonly used at present in amphibious operations. It is entirely suitable for naval gunfire purposes and may be considered standard in the absence of specific instructions to the contrary. In section VII (Illustrative Problem, figs. 9, 10, 11, 12) an M-square grid system has been superimposed on the map of the area.

523. Fire-support areas.--By the assignment of a definite sea area to each fire-support group, firing ships are allowed freedom of maneuver in the execution of fires and at the same time are prevented from interfering with transports, boat groups and other fire-support groups. The area assigned each group must, of course, be suitable from the standpoint of depth of water and absence of navigational hazards. Subject to this prime requisite the most important consideration in the assignment of fire-support areas is the ability of the fire-support group to cover effectively all important parts of its target area with fire. The fire-support area must therefore be of such size that positions are afforded which are within range of the most distant target assigned and that other positions are afforded at ranges which permit angles of fall sufficient to engage defiladed targets. Or the area must extend laterally to a position from which fire can be delivered behind the mask. In most cases it will be preferable to assign fire-support areas by showing the space in which the fire-support groups must not operate rather than by specifically restricting a fire-support group to a certain area. It may sometimes be desirable or necessary to assign two fire-support groups to the same fire-support area. This will always be the case, of course, for example, if a single cruiser constitutes a close fire-support group with its 5-inch batteries and a deep fire-support group with its larger batteries. All ships in one fire-support area will normally maneuver as a single unit. Figure 5 illustrates the assignment of fire-support areas.

524. Firing runs.--Firing runs are planned by the fire-support groups within the limits of the respective fire-support areas. The bearing of the firing runs in relation to the line of fire should be such that all the guns of the battery or batteries concerned can bear, and that the range and deflection to the target or targets engaged on the run will change as little as possible during the period of adjustment and fire for effect. The turns at the ends of the run must be made at such times that they do not interfere with the delivery of fires scheduled for specific times nor interrupt the execution of fire on a target of opportunity. From the standpoint of effective delivery of fire the ideal firing run is on a straight course of maximum length and at minimum speed with the center of the target area bearing on the beam at the center of the run. (See Fig. 6a.) Where high speed and frequent change of course are necessary as part of planned protective measures, irregular firing runs may be prescribed as illustrated in Fig. 6b. The firing legs of such runs however must always be of such length as to permit the execution of at least one fire mission (normally at least 7 minutes) and should be as close to perpendicular to the line of fire as possible. Special firing runs for specific periods may be planned and executed for definite missions. Figure 7 illustrates special destroyer runs for participation in the preparation. Such runs are coordinated exactly with the movement of the assault boat wave.

Figure 5.--Assignment of fire support areas by diagram.

Figure 6.--Regular and irregular firing runs.

Figure 7.--Two type of destroyer runs in Phase II, Covering the Beach Assault.

525. Target areas.--Each fire-support group is assigned a definite land area within which all fires normally to be expected from the group are located. These target areas in general coincide with the zone of action of the landing force unit with which the fire-support group is associated in the attack. Thus Fire Support Group 1, in close support of the first Battalion, Fifth Marines, should be assigned a target area which includes the objective of the First Battalion and the areas immediately related to it. Fire Support Group 3, in deep support of the Fifth Marines, should be assigned a target area including the regimental objectives. The target area of a deep support group therefore will normally include the target areas of two or more close support groups as well as other areas beyond. The area of observation assigned the ship's airplane should also correspond to the ship's target area.

526. Time schedules.--The device of a time schedule is used for three principal purposes.

     1. In phase I to insure that fire-support groups will carry out all missions assigned by indicating the times at which the missions will be executed so that the firing ship and the air observer will be in proper position during the periods specified.

     2. In phase II the time schedule, in addition to having the same purpose for some fires as in phase I, has the more critical mission of coordinating the preparation fires delivered on the beach areas with the movement of the assault boat waves and with the actions of combat aviation. Fires on time schedule are listed to be executed so many minutes before or after H-hour (H-16 or H+11). Similarly, combat aviation may be assigned dive-bombing and strafing missions on a similar time schedule. H-hour is the predicted time at which the first boat wave will reach the beach. The actual time of the arrival of the first boat wave will rarely be exactly as planned. If a change in the time is foreseen sufficiently in advance, a general signal changing the clock time of H-hour will be broadcast. But last-minute delays occasioned by many causes may result in the arrival of the assault wave so long after the planned time that the preparation fires, if delivered on schedule, will have lost some of their effectiveness. It is also possible that the boat waves will land a few minutes prior to H-hour and thus be subjected to the fires of their own ships. To avoid these eventualities fire-support groups should on their own initiative delay the time of execution of the preparation fires (or repeat them) or should cease firing if direct observation indicates the necessity for such action. Ship observers and air observers must be alert during the critical period of the beach assault to follow the actual movement of the boats and make the fires conform. Similar steps should be taken to insure that the naval gunfire does not endanger friendly planes arriving to dive bomb or strafe or smoke the beach just prior to the assault. All firing ships should be furnished with a copy of that portion of the order which prescribes low flying airplane attacks. The Naval Gunfire Plan and the Air Support Plan should be closely coordinated to achieve maximum results and to avoid duplication of effort.

     3. In phase III, the time schedule again serves the same purpose as in phase I and may have the additional function of coordinating naval gunfire with landing force activities ashore. For a particular part of the attack such as the assault of a known, clearly defined strong point, the time of the attack may be scheduled at a fixed hour; and a time schedule of fires may be furnished a ship or ships to be executed in support of this operation. In this case the fires should be delivered exactly as scheduled and the troops must conform strictly to the schedule laid down. Such schedule fires are usually of value only if ample time for planning is available, and if adequate communication facilities between the troops and the ship are not at hand. With direct communication in operations between the ship and the attacking troops, it is normally preferable to fix the time of commencing and ceasing fire on particular targets or a series of targets by message.

527. Liaison Officers.--The two types of liaison officers are discussed in paragraph 516. These officers, representing the units from which they come to the commanding officer of the unit to which they are sent, will be the most valuable means of effecting coordination between firing ships and supported units during phase III, when tactical situations will arise which were unforeseen and which must modify the prearranged plan. Their recommendations on the use and the delivery of naval gunfire should be asked for continuously and given due consideration. The competence of the officers assigned these tasks must be unquestioned and the communications provided them must be as certain as possible.

528. Observers.--The use of observers in assisting to coordinate the preparation fires with the movements of the assault waves has already been noted in paragraph 526(b) above. During phase III the use of landing force artillery officers as the Shore Fire-Control Party spotters for naval gunfire will further insure the coordination of naval gunfire with the movement of the front-line troops. These spotters normally accompany the leading echelons of the assault battalions and in the execution of their mission must be completely informed of the local situation

and must have direct observation of the critical front-line areas. Their requests for fire on certain areas are a sure indication of the progress of the attack. Since these spotters come from the artillery unit which is part of the combat team operating in that area, effective coordination with landing-force artillery is easily achieved. At the time that artillery batteries are in position to support the infantry regiment to which he is attached or which he is supporting, the artillery battalion commander should insure that both the liaison officers and the spotters are informed in order that targets which can be more effectively engaged by artillery will not be engaged by ships' gunfire.
1. Special Signals.--Coordination with movement of boats, with aircraft, and with elements of the landing force may be achieved under certain conditions by using special signals such as flares, lights, etc. When other means of communication are lacking, such signals may be the only means of requesting "on call" fires or of requesting "Cease fire." The use of such signals however should be severely restricted, their meaning should be unmistakable, and the probability of similar signals originating from enemy sources should be taken into account.

Section V
Techniques

Par.
530.	General	131
531.	Target designation	131
532.	Engagement of targets	132
533.	Methods of fire control	133
534.	Spotting	133

530. General.--The techniques herein described have been developed in training and tested, most of them in combat. They offer a solution to the problems, and are presented for use when desired or for use when no other technique is prescribed by competent authority. It must be borne in mind that a technique is designed for a certain type of equipment; and that any change in equipment may render a technique obsolete. Technique is not doctrine; the responsibility of the commander for prescribing a suitable technique for an operation and of training the components of his Force in the execution of the technique is doctrine.

531. Target Designation.--

     1. Targets on time schedule are designated by coordinates or preferably by marked photo, marked map or by overlay prepared for the photo or map, contained in the Naval Gunfire Annex of the operations order. A circle of standard size (100, 200, 300, or 400 yards in diameter) is drawn around the area in which the target is located, the circles are identified by numbers and are referred to as "concentration No. 6," etc. The size of the circle used depends on the effect desired and on the type battery assigned; on targets to be neutralized, a 200-yard circle may be used for 5-inch battery targets, a 300-yard circle for 6-inch battery targets, and a 400-yard circle for 8-inch or larger battery targets. If such refinements in the preparation of the gunfire Annex are not practicable, due, for instance, to the fact that the number of batteries by caliber is not known far enough in advance, the circles representing targets to be neutralized should be all of 200-yard diameter in order to insure that there will be no gaps in the preparation. These gaps will result if larger circles are drawn and 5-inch batteries with 200-yard patterns are used in the execution of most of the fires. The center of the circle is the point at which it is desired to place the mean point of impact. If the order furnishes only the coordinates, the coordinates of the center of the target are given and the circles may be drawn by the firing ships for ease in identification. The use of marked oblique photographs to supplement the designation of these targets to ships and low-flying observing planes will facilitate identification on D-day.

        Panoramic strip mosaics prepared from photos taken from seaward by ships or by planes flying at very low altitudes should be furnished firing ships if possible in order that gunnery personnel may become familiar in advance with how the target area will actually look on D-day. These mosaics should show:

        1. The grid lines most normal to the coast (E-W or N-S lines).

        2. The name or number of visible hills.

        3. The location of terrain features not apparent (river mouths, low promontories, etc.).

        4. Landing beaches to be used.

        5. Exact location of all targets that show.

        6. Any other information of value.

Marked vertical photographs are preferable for air observers operating at heights above 1,000 feet.
2. Targets on call are designated as for those on time schedule.

3. 1. Targets of opportunity may be designated by coordinates, or they may be designated by reference to a numbered concentration with an appropriate shift. For example: "Concentration No. 5. Down 200, left 400, etc.," means that a target has been discovered whose center is approximately 200 yards short of, and 400 yards left of, the center of the circle designating concentration No. 5. Or they may be designated by a simple shift from the target on which the battery concerned is firing or on which it has just completed firing. Thus if an observer sends a message to a ship which is firing for effect on a target previously designated by the observer, such as "new target, up 300, right 100, etc.," it means that a target has been discovered whose center is approximately 300 yards beyond and 100 yards right of the mean point of impact of the salvos being fired. If an observer uses coordinates to designate a target of opportunity, the coordinates should refer to the standard map in effect for the operation. However, in an emergency, polar coordinates may be used. An unmistakable terrain feature should be named as origin and the bearing and distance of the target center from the origin is given. For example, "Target bears 300° True (or Magnetic), distance 5,000 yards, from Point Vaca)."

   2. It should be noted that targets may be designated to observers as well as to firing ships. Thus a landing force unit commander or his naval gunfire liaison officer may direct a ground or air spotter to adjust fire on a target designated by any one of the above methods.
532. Engagement of Targets.--The execution of a fire mission is divided into three parts: Determination of initial data for laying the guns, adjusting the mean point of impact on the center of the target, and the delivery of fire for effect. The technique employed in each of these three operations may vary according to the type of fire control employed (direct or indirect), and according to the tactical purpose of the fire and the importance of the target.

     1. Direct fire.--The use of direct fire implies that the target is visible from the firing ship.

        1. The range to the center of the target is determined by radar or rangefinder. Continuous ranging on the beach line is sufficient for targets in the vicinity of the beach, since the distance of such targets from the beach may be accurately estimated. Care must be taken to insure that the rangefinder operator is on the proper target. If rangefinders are not available a range from navigational plot may be used. Aiming points in deflection and in elevation are selected and the offsets applied. For prearranged fires a study of oblique photographs will often permit the selection of aiming points in advance. The aiming points should be outside the target area if it is probable that they will be obscured by the initial bursts. The aiming point in deflection should be at approximately the same range as the target in order that the offset will remain relatively constant. The shore line is a convenient aiming point in elevation, particularly for targets close to the beach. The range tables will give the necessary range change to compensate for differences in angle of position between the elevation aiming point and the target, if this difference is material.

        2. Ranging salvos are fired, observed, and spotted to bring the mean point of impact on the center of the target. With 6-inch guns and larger, one turret may be used satisfactorily for adjustment. For the 5-inch calibers at least 4-gun salvos should be used. From 3 to 5 salvos will normally be required to establish the hitting gun range. For this reason, as well as to allow time for turns in the firing run, the Gunnery Annex should allow at least 10 minutes for each time schedule target. The exact times shown (H-15, etc.) for the targets are subject to minor adjustments by the firing ships to take care of rapid or unduly long adjustments and to permit turning. In the event a ship becomes hopelessly out of step with the time schedule the commanding officer must decide whether it is better to continue to fire by the times prescribed, or to fire on targets in the order prescribed, the determining factor being which method will better aid the troops. Ranging salvos are fired with all guns laid at the same range and parallel to each other in deflection.

        3. As soon as the hitting gun range is established, fire for effect is commenced with all guns of the battery assigned to the mission. Unless otherwise specified in the Gunnery Annex, all targets will be neutralized and fire for effect will be accomplished by the execution of rapid fire for 2 minutes with 5- or 6-inch batteries (approximately 80 rounds and 60 rounds, respectively) and for 3 minutes with 8-inch batteries (approximately 54 rounds). All guns are fired at the same range throughout, normal dispersion accomplishing the desired coverage, and parallel to each other in deflection. If adequate coverage of the area in width is not obtained during the first few salvos, a deflection change is ordered for the succeeding salvos.

2. Indirect fire.--The use of indirect fire implies that the target is not visible to the firing ship. However, these fires will usually be observed and adjusted either by air spot or by Shore Fire Control Party spotters.

   1. The range to the center of the target is determined by measuring a line joining the ship's position (fixed by continuous navigational plot) and the point designated as the center of the target by the observer (either by coordinates or by reference to a plotted concentration). It is for this reason that a standard map or chart on which has been superimposed the standard grid, and which includes the fire support areas, should be furnished to all firing ships. To the range thus determined is added the position correction necessary because of the altitude of the target. The true bearing of the target is determined and the guns are laid with an appropriate deflection.

   2. Adjustment is accomplished as for direct fire except that full battery salvos are normally used. After each ranging salvo, fire is suspended until the spot is received and applied.

   3. When adjustment is complete and the spotter requests fire for effect, neutralizing fire is delivered as in the engagement of targets by direct fire. If the target has not been sufficiently covered in area or in density, the spotter will transmit an appropriate spot (if necessary), and request that fire for effect be repeated.

3. Ammunition.--Appropriate projectiles, fuzes and charges for certain targets, and for target areas, should be decided on prior to D-day from a study of the character of the targets and the relation of the target area to the fire support area in range and mask. Unless otherwise specified, targets are to be neutralized, and therefore high explosive AA common or HC projectiles should be used with the fuze which will give the maximum effect (see par. 508 above). If AA shell with air burst is to be used for effect, adjustment is usually carried out with impact burst and when the hitting gun range is determined, the trajectory is raised above the target approximately 20 to 30 yards to produce the air bursts. It should be noted that effective air burst is usually obtained with nondelay impact fuzes when the target area is heavily wooded. Under such conditions the impact fuzes should be used. The type charge for HC projectiles (normal or reduced) and the range band for AA projectiles (below or above 45°) required to reach certain areas should be determined in advance and a standard procedure for use during the operation should be prescribed on each ship.

4. Special targets.--The great bulk of targets will be targets on which fire for neutralization as above outlined will be delivered. Certain targets however will require special attention, such as targets to be destroyed and some targets fired on in deep support.

   1. Targets to be destroyed will normally be engaged by not more than a single turret. Adjustment is continuous throughout the mission and the mission is continued until destruction is obtained. Delay fuzes are used and armor piercing, common, or HC projectiles are employed, depending on the penetration required. The amount of ammunition and the length of time required for each target can be predicted only in the most general terms; consequently batteries assigned destruction missions should not be included in the fire plan for close support of battalions or deep support of regiments.

   2. Some deep supporting fires are placed in areas the free use of which should be denied the enemy, such as cross roads, bridges, fords, etc., Also some fires in deep support may be executed solely for their annoyance value. These missions may well be accomplished with less than the standard allotment of ammunition for neutralization fires. If it is so decided, it is usually better to continue the fire over the period designated but at a slower rate of fire. Such fires (for interdiction and harassment only) should be executed only if there is ample ammunition above the requirements of other fires.
533. Methods of Fire Control.--Methods of fire control for both direct and indirect fires have been indicated under paragraph 532 above. The detailed mechanics of the various operations required--in navigation, in plot, at the director and at the guns are here purposely omitted. Standing operating procedures should be prescribed for each ship, depending on its equipment, to accomplish the desired result.

534. Spotting.--The technique of spotting naval gunfire on shore targets by ship observers is in every respect similar to that employed in spotting fire against waterborne targets, except that the effect of slope must be taken into consideration when making range changes. The technique of spotting by air observers and by Shore Fire Control Party spotters is laid down in the Shore Fire Control Code. Any variations in the procedure therein prescribed should be specifically authorized by the Commander, Naval Attack Force. In general, it is desirable that the same system of spotting be employed by air observers, by Shore Fire Control Party spotters and by field artillery forward observers. In this way maximum flexibility in the use of spotters is obtained without confusion.

Section VI
Naval Gunfire Annex

Par.
535.	Formulation	134
536.	Essential elements	134
537.	Simplicity	134

535. Formulation.--The Naval Gunfire Annex is that part of the Naval Attack Force Order which contains the directions for furnishing naval gunfire support for the landing force. Its preparation is a joint function of the staff of the Commander Attack Force and the staff of Commander Landing Force. Before it can be drawn up, the number and type of ships and the amounts of ammunition available must be known, the scheme of maneuver must have been decided on, and the minimum requirements in ships and ammunition for the various phases of D-day must have been estimated.

536. Essential elements.--The Naval Gunfire Annex must contain specific information on the following points:

     1. The composition of each fire support group.

     2. The mission(s) of each fire support group.

     3. The fire support area(s) for each fire support group.

     4. General target area assigned each group.

     5. Specific targets assigned each group, the nature of the targets, if known, the effect desired, and the time of engaging each.

     6. The landing force unit each fire support group supports and the liaison to be effected.

     7. The observer(s) for each group and the communication provided.

     8. Any restrictions imposed on movements or firing.

     The annex should include appropriate charts and diagrams whenever practicable.

537. Simplicity.--The guiding principle in the formulation of the Naval Gunfire Annex is simplicity.

Section VII
Illustrative Problem

Par.
538.	General	134
539.	Mission of the Naval Attack Force	134
540.	Landing Force scheme of maneuver	135
541.	Fires required	135
542.	Number of fire support groups	136
543.	Composition and location of the fire support groups	136
544.	Preparation of the Naval Gunfire Annex	136

538. General.--The following illustrative problem is presented for the purpose of suggesting a procedure which may be followed in planning naval gunfire support. Considering the many variations that may be more applicable or necessary, the methods shown below should be regarded only as a general guide.

539. Mission of the Naval Attack Force.--

     1. It is assumed that a naval attack force has been assembled and assigned the mission of projecting a military force ashore on an enemy island to seize a beachhead sufficient to permit the conduct of further operations.

     2. Intelligence reports as outlined in the Intelligence Annex have been studied and it has been concluded that the enemy defending this island consists of one division of approximately 15,000 men, organized with 3 regiments of infantry, 4 battalions of light and medium artillery, 1 battalion of tanks, with the necessary engineer, service and medical troops. This defense force is supported by a local naval defense force, and an undetermined number of land-based aircraft. It must be understood that we will be carrying on a continuous reconnaissance of the island with all available agencies. Further, preliminary operations will be instituted prior to D-day to neutralize seacoast batteries and the defending enemy air force.

     3. The attack force includes combatant ships and the First Marine Amphibious Corps, consisting of Corps Troops and two Marine Infantry Division. The basic plan calls for the projection of the First Marine Division ashore in area X, with the Second Marine Division landing in area Y, the two divisions to effect a junction, seize a beachhead and be prepared for further operations on shore. This will necessitate the formation of naval fire support groups to support the First Marine Division landing in area X, and the Second Marine Division, landing in area Y. (see fig. 9.)

4. From the intelligence reports it is indicated that area X and the terrain contiguous thereto (see fig. 10) is defended by one regiment of infantry, supported by one light artillery battalion and probably one medium artillery battery. The enemy in this area is apparently maintaining an active defense, with light defenses manned on the probable landing beaches, with observation of the remainder of the coastline and with the bulk of his troops bivouacked in the hills in reserve.

5. Preliminary study of the needs of both Marine Divisions has been made by the staffs of Commander Landing Force and of Commander Naval Attack Force and it has been decided that 8 destroyers, 6 light cruisers (but none of the 16 5-inch guns type) and 1 heavy cruiser will be available for naval gunfire support on D-day to support the First Marine Division. Ample stocks of shore bombardment ammunition of the most suitable types are available. Examination of available charts indicates that no navigational hazards exist to interfere with the operation of fire support vessels off the proposed landing beaches. Sufficient gunfire is therefore available to permit the planning of an assault on a wide front. (See par. 512.)
540. The Landing Force scheme of maneuver.--The Commander of the First Marine Division has prepared a scheme of maneuver (see fig. 10) requiring the simultaneous landing of two assault regiments, each regiment with two battalions in the assault echelon. The plan calls for the seizure of objective O^a by H plus 1 hour, and the further seizure of objective O¹ by H plus 5 hours.

541. Fires required.--

     1. The staff of the first Marine Division Commander now outlines on the map prepared for the operation the probable target locations, based on presently known and probable enemy dispositions in the area to be attacked. (See fig. 11.)

     2. Analysis of Targets.--Nos. 1 to 32--Probable beach defenses.

        Nos. 34, 42, 45, 46, 47, 56--Routes of approach of enemy forces to probable and known defensive positions.

        Nos. 33, 35, 36, 37, 38, 39, 40, 41, 43, 44, 38, 49, 50, 51, 52, 53, 54, 55--Possible strongpoints. Terrain features most likely to be occupied by enemy forces, and which, if occupied, would present a serious threat to our advance.

        No. 57--Possible enemy command post.

        Nos. 58, 59, 60, 61, 62, 63, 64--Critical points on road communication net.

        NOTE--Additional intelligence data will probably be obtained by reconnaissance agencies; it is anticipated that such data will permit the designation of enemy battery positions and other targets prior to D-day.

     3. Target Requirements.

        Phase I: (Deep Support)	Nos. 57, 58, 59, 60, 61, 62, 63, 64 (8 6- or 8-inch battery targets) on time schedule; targets of opportunity as practicable; air-spot. Nos. 32, 34, 42, 45, 46, 47, 56 (7 5-inch battery targets) on time schedule; ship spot.
        Phase II: (Preparation)	Nos. 1 to 32 (inclusive), 33, 34, 37, 38, 39, 42, 35, 36, 43, 44, 45, 46, 47 (45 5-inch battery targets), ship spot. Repeat the 8 6- or 8-inch battery targets of phase I; air-spot.
        Phase III:      (Close Support)	Nos. 33, 34, 37, 38, 39, 40, 41, 42, 35, 36, 43, 44, 45, 46, 47, 48 (16 5-inch battery targets) (ship spot). SFCP engage targets of opportunity upon establishment ashore.
        (Deep Support)	Targets of opportunity by air-spot beyond Oa until H plus 45 minutes, then beyond O1 until H plus 4 hours, 30 minutes. Fires short of these lines only on request of landing force units ashore.

     4. Capabilities of Fire-Support Ships. (See par. 511, fig. 3.)

        8 DD's	64	5-inch battery targets (200 x 200).
        6 CL's	154	5-inch battery targets (200 x 200).
        	135	6-inch battery targets (300 x 300).
        1 CA	24	5-inch battery targets (200 x 200).
        	10	8-inch battery targets (400 x 400).
        Total Shore Target Capacity:
        	242	5-inch battery targets (200 x 200).
        	136	6-inch battery targets (300 x 300).
        	10	8-inch battery targets (400 x 400).

One-half of this capacity should be reserved for fires on targets of opportunity during phase III (see par. 507c(2)). This will allow, for scheduled fires during phases I and II and the first part of phase III, the following:

121	5-inch battery targets.
68	6-inch battery targets.
5	8-inch battery targets.

The following have already been scheduled:

---

		| | |	5-inch battery targets	| | |	6- or 8-inch battery targets
During Phase	I	|	7	|	8
	II	|	45	|	8
	III	|	16	|	0
Total scheduled fires		|	68	|	16

The number of scheduled fires is well within the allowance, permitting the scheduling of many more targets elected as a result of continuous reconnaissance and later intelligence reports.

From this analysis, it is thus seen that the requirement for time schedule fires already planned, as well as for those which probably will be planned from results of future reconnaissance, is well within the capabilities of the fire-support ships during all phases.

542. Number of Fire Support Groups.--Since there are two assault regiments, each with two assault battalions landing simultaneously, a minimum of six fire support groups is indicated:
     1 Close Fire Support Group per assault battalion.
     1 Deep Fire Support group per assault regiment.
     Eight destroyers, 6 CL's, and one CA will be available to support the attack of the First Marine division on D-day. The target analysis indicates that one light cruiser is adequate for each battalion and regimental Fire Support Group. Therefore, 9 fire support groups should be set up; i.e., 2 Special Mission Fire Support groups of 4 destroyers each, to assist in the preparation, 4 Fire support groups of 1 CL each to provide close support for the assaulting battalions, 2 Fire Support Groups of 1 CL each to provide deep support for the First and Fifth Marines, and 1 Fire Support Group consisting of the 1 CA to provide deep support for the First Marine Division.

543. Composition and Location of the Fire Support groups.--The composition and location of each fire support group is dependent on the probable number, range and direction of targets in each area and on the hydrography of the sea approaches. It has already been determined that the sea approach presents no restrictions on the use of fire support groups; therefore, the composition has been (see par. 542 above), and the location of the fire support groups can be, based entirely on the targets to be engaged. The assignment of fire missions is a function of the staff of the Commanding General, First Marine division, and includes coordination of the fires with the movement of the landing force components both in boats and on the shore. The composition of the fire support groups and the location of the fire support areas, and the coordination of the fire support groups with the movements and positions of the other naval components of the attack group, including combat aviation, is the function of the staff of the Commander Naval Attack Force. The staffs must consult with each other to insure agreement of the two aspects of the problem.

544. Preparation of the Naval Gunfire Annex.--The combined staffs of the Commander Naval Attack Force and First Marine Division now prepare the plan of Naval Gunfire. Upon approval, this plan is authenticated and issued as the Naval Gunfire Annex. The following appendices must be prepared and attached thereto, i.e.:

     1. Plan of Naval Gunfire (prepared by joint staffs).
     2. Time Schedule (prepared by joint staffs).
     3. Fire Support Areas (prepared by NAF).
     4. Radio Frequency Plan (prepared by NAF).
     5. Composition of Liaison and Shore Fire Control Parties (prepared by joint staffs).

     Figure 13 is a Plan of Naval Gunfire for support of the First Marine Division in the attack. Figure 14 is a sample time schedule. Figure 12 shows the fire support areas assigned. . The composition of the Shore Fire Control Parties and the personnel assigned liaison duties as well as the radio frequency assigned each is shown in figure 15.

Figure 9.

Figure 10.

Figure 11.

Figure 12.

Plan of Naval Gunfire

FSG	Composition	Mission	Phase I	Phase II	Phase III
I	DesDiv 4 (4 DD's)	Special, 1st Marines	Screen Transports	Preparation. Targets 1 to 12 (incl.) (ship spot).	Move to east flank. Fire on targets of opportunity flank of 01 (ship spot).
II	DesDiv 2 (4 DD's)	Special, 5th Marines	Screen Transports	Preparation. Targets 21 to 32 (incl.) (ship spot).	Move to west flank. Fire on targets of opportunity flank of 01 (ship spot).
III	CL	Close Support, 1st Battalion, 1st Marines		Targets 9, 10, 11, 12, 13, 33, 34, 37 (ship or air spot).	Targets 33, 34, 37 (ship or air spot). Thereafter on call SFCP.
IV	CL	Close Support, 2nd Battalion, 1st Marines		Targets 14, 15, 16, 17, 18, 38, 39, 42 (ship or air spot).	Targets 38, 39, 40, 41, 42 (ship or air spot). Thereafter on call SFCP.
V	CL	Close Support, 1st Battalion, 5th Marines		Targets 19, 20, 21, 22, 23, 35, 36, 43, 44 (ship or air spot).	Targets 35, 36, 43, 44, 48 (ship or air spot). Thereafter on call SFCP.
VI	CL	Close Support, 2nd Battalion, 5th marines		Targets 24, 25, 26, 27, 28, 45, 46, 47 (ship or air spot).	Targets 45, 46, 47 (ship or air spot). Thereafter on call SFCP.
VII	CL	Deep Support, 1st Marines.	Targets 34, 42, 57, 62 (ship and air spot).	Repeat targets 34, 42, 57, 62 (ship and air spot).	Targets of opportunity zone of action 1st Marines beyond Oa until H plus 45, then beyond O1 until H plus 4 hours 30 minutes (air spot). Answer calls ground units.
VIII	CL	Deep Support, 5th Marines	Targets 32, 45, 46, 47, 56, 58, 59, 60, 61 (ship and air spot).	Repeat targets 32, 45, 46, 47, 56, 58, 59, 60, 61 (ship and air spot).	Targets of opportunity zone of action 5th Marines beyond Oa until H plus 45, then beyond O1 until H plus 4 hours 30 minutes (air spot). Answer calls ground units.
IX	CA	Deep Support. First Marine Division	Targets 63, 64 (air spot).	Targets 63, 64 (air spot).	Search for targets of opportunity outside of O1 (air spot). Use either 5- or 8-inch battery on appropriate targets.

Figure 13. Targets in italics are 6- or 8-inch Battery targets.

Naval Gunfire Time Schedule

FSG	Target	Time
I	9, 10, 11, 12   5, 6, 7, 8   1, 2, 3, 4	H-25   H-15   H-5
II	21, 22, 23, 24   25, 26, 27, 28   29, 30, 31, 32	H-25   H-15   H-5
III	34   33, 37   9   10, 11   12, 13	H-45    H+20   H-35    H+10   H-25   H-15   H-5
IV	42   38, 39   18   16, 17   14, 15   40, 41	H-45    H+20   H-35    H+10   H-25   H-15   H-5   H+30
V	43, 44   35, 36   19   20, 21   22, 23   48	H-45    H+20   H-35    H+10   H-25   H-15   H-5   H+30
VI	47   45, 46      28   26, 27   24, 25	H-45    H+20   H-35    H+10   H-25   H-15   H-5
VII	34   42   57   62	H-120    H-35   H-100    H-25   H-80   H-15   H-60    H-5
VIII	60, 61   58, 59   56   45, 46   32, 47	H-120    H-45   H-100    H-35   H-90    H-25   H-80    H-15   H-60    H-5
IX	63   64	H-120    H-15   H-100    H-5

Figure 14.

Composition of Liaison and Shore Fire Control Parties With Frequencies Assigned

Group	Furnished by--	Composition	Report to--	Radio channel*
				Primary	Alternate
NGF Ln O 3	FSG3	1 Lieutenant, USN	1st Bn 1st Mar	F3	F1
Bn Ln O 3	1st Marines	1 Captain, USMC	FSG3	F3	F1
SFCP 3	1st Marines (Reinforced)	1 Lieutenant, USMC (Artillery) 8 enlisted, USMC	1st Bn 1st Mar	F3	F1
NGF Ln O 4	FSG4	1 Lieutenant USN	2d Bn 1st Mar	F4	F1
Bn Ln O 4	1st Marines	1 Captain, USMC	FSG4	F4	F1
SFCP 4	1st Marines (Reinforced)	1 Lieutenant, USMC (Artillery) 8 enlisted USMC	2d Bn 1st Mar	F4	F1
NGF Ln O 5	FSG5	1 Lieutenant USN	1st Bn 5th Mar	F5	F2
Bn Ln O 5	5th Marines	1 Captain, USMC	FSG5	F5	F2
SFCP 5	5th Marines (Reinforced)	1 Lieutenant, USMC (Artillery) 8 enlisted USMC	1st Bn 5th Mar	F5	F2
NGF Ln O 6	FSG6	1 Lieutenant, USN	2d Bn 5th Mar	F6	F2
Bn Ln O 6	5th Marines	1 Captain, USMC	FSG6	F6	F2
SFCP 6	5th Marines (Reinforced)	1 Lieutenant, USMC (Artillery) 8 enlisted USMC	2d Bn 5th Mar	F6	F2
NGF Ln O 7	FSG7	1 Lieutenant, USN	1st Marines	F1	F9
Regtl Ln O 7	1st Marines	1 Captain, USMC	FSG7	F1	F9
NGF Ln O 8	FSG8	1 Lieutenant, USN	5th Marines	F2	F9
Regtl Ln O 8	5th Marines	1 Captain, USMC	FSG8	F2	F9
NGF Ln O 9	FSG9	1 Lieutenant, USN	1st Division	F9
Division Ln O 9	1st Marine Division	1 Major, USMC	FSG9	F9

* See Signal Communication Annex for frequencies assigned.

Figure 15.

[B L A N K]

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