Cover of booklet. CONFIDENTIAL

PHIB-4     


AMPHIBIOUS OPERATIONS
THE PLANNING PHASE

(NAVMC-3985)
Marine Corps Schools logo.
1945
No. 4 in a Series of
Amphibious Operations


Published--
For Instructional Purposes Only.

 

MARINE CORPS SCHOOLS
MARINE BARRACKS, QUANTICO, VIRGINIA





 

MARINE CORPS SCHOOLS
MARINE BARRACKS, QUANTICO, VIRGINIA

September 1945.

"Amphibious Operations - The Planning Phase" is approved and published for instructional purposes in the Marine Corps Schools.

OLIVER P. SMITH,
Brigadier General, U.S. Marine Corps,
Commandant.

 


AMPHIBIOUS OPERATIONS--THE PLANNING PHASE
TABLE OF CONTENTS

Section 1
GENERAL
  Paragraph Page
Introduction       1         1    
Unified Command   2     2  
Coordination of Planning   3     2  
Liaison   4     5  
Section 2
HIGHER-ECHELON PLANNING
Origin and Analysis of the Strategic Mission   5     7  
Determination of Objectives   6     7  
Designation of the Task Force   7     8  
Size and Composition of the Task Force   8     8  
Section 3
PLANNING AIDS
Planning Schedules   9     11  
Section 4
INTELLIGENCE
General   10     13  
Initial Requirements   11     13  
Agencies Available   12     13  
Intelligence Plans   13     14  
Security of Information   14     15  
Section 5
ESTIMATE OF THE SITUATION
General   15     17  
Attack Force - Landing Force Level   16     17  
Concurrent Joint Estimate   17     17  
Responsibilities of Naval and Ground Commanders   18     17  
Adjustment of Decisions   19     17  
Factors of an Estimate   20     17  
Section 6
PLAN OF ACTION
General   21     19  
Preferred Plan   22     19  
Alternate Plan   23     19  
Selection of Alternate Plans   24     19  
Form of Alternate Plans   25     19  
Section 7
DETAILS OF THE PLAN
Scheme of Maneuver   26     21  
Time of Landing   27     21  
Ship-to-Shore   28     22  
Communication   29     22  
Logistics   30     22  
Naval Gunfire Support   31     23  
Air Support   32     23  
Annexes   33     23  
Section 8
TRAINING
General   34     25  
Training Objectives, Land Phase   35     25  
Training Objective, Ship-to-Shore Phase   36     25  
Section 9
EMBARKATION
General   37     27  
Joint Planning and Liaison   38     27  
Standing Operating Procedure   39     27  
Transport Quartermasters   40     27  
Phases of Embarkation   41     28  
Plans and Orders   42     28  
Control   43     28  
Section 10
REHEARSALS
Purpose   44     29  
Extent of Rehearsals   45     29  
Timing   46     29  
Plans and Orders   47     30  
Replacement of Losses   48     30  
Section 11
SHORE-To-SHORE
Definition   49     31  
General   50     31  
Characteristics   51     31  
Logistic Support   52     32  
LIST OF ILLUSTRATIONS
  Figure Page
Sequence and coordination of planning for an amphibious operation   1       3    

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Section 1
General

1. General.--a. The complexity of modern amphibious operations involving participation by ground, air, and surface forces requires a much higher degree of detailed planning and coordination than is required for normal land warfare. In addition, the high degree of coordination required of all forces engaged in a landing on a hostile shore necessitates that orders to subordinate units be in much greater detail than is considered necessary in land warfare. Success in placing troops on the beach in battle formations necessitates careful planning of all details by higher headquarters. Failure to insure this success invites certain disaster, for there are no possible positions upon which troops can fall back for reorganization. Attempts to withdraw and reembark in the face of an alerted enemy will result in heavy losses.

b. The very nature of amphibious operations requires that planning be started far in advance of D-day. Between inception of planning and D-day the enemy situation may change considerably, or the composition of our own forces may be changed, requiring a change in plans. Prior to embarkation, however, plans should be established in their final form and changed thereafter only if a serious change in the enemy's situation so warrants. It is essential that commanders of every echelon hold briefing conferences with their subordinates prior to embarkation to eliminate any possibility of confusion or misunderstanding of the plans. Once troops are embarked in transports, it is most difficult to effect a change of plans. Once troops are embarked in small boats and committed to action, an attempt to change plans will result in confusion

c. The use of the air arm as a supporting weapon in amphibious operations is as much a matter of doctrine as is the employment of naval gunfire and artillery. Consequently, no special mention is made of the air arm in discussions to follow, but it must be understood that in planning for any amphibious operation provisions must be made for full and coordinated use of the strategic and tactical air forces.

d. Operation plans as issued for amphibious operations are in the form of orders but are not effective until so ordered. The reason for this is that a considerable period of time elapses between the time plans are made and the time of execution and, in order to adequately cover all eventualities, several plans may be issued without any indication of which one will be executed. When it can be determined which plan is to be employed, it is usually made effective on signal, although in some cases the plan itself may contain a statement that it will become effective at a certain time.

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2. Unified Command.--a. Adherence to the principle of unity of command, which vests in one commander the sole responsibility for the planning and conduct of an operation as a whole, is vital to the success of an amphibious operation. Similarly, each of the various task forces which comprise the total force engaged in the operation should be under a single commander, regardless of the fact that these task forces may be composed of elements of two or more services.

b. Unity of command permits timely decisions to be reached and orders to be issued to meet the rapidly changing situations encountered in modern warfare. It insures that the "council-of-war" procedure inherent in a joint command system, with its attendant delay and confusion, is obviated.

c. The geography of the theater of war and the balance of air, naval, and military forces therein determine whether the theater should be under a ground, air, or naval commander. Similar considerations are involved in determining the command of any subordinate part of the theater or of any joint operation conducted within it.

3. Coordination of Planning.--a. To insure complete understanding and singleness of purpose, planning at all stages, and in all echelons concerned, must be coordinated between participating services. Commanders and staffs of the various echelons of the participating services should be assembled for planning purposes at the headquarters of the next higher commander as soon as practicable after such higher commander has received his directive. By such means alone can mutual problems be understood and maximum coordination effected.

b. Specialists in any of the various services, or from civilian life, should be consulted freely when their peculiar knowledge is necessary to the proper planning of amphibious operations.

c. When amphibious operations are conducted repeatedly over a long period of time, the utmost cooperation and coordination will be achieved with a minimum of planning and issuance of orders if the same naval transport division, transport group, naval attack force, and logistic control group staffs are assigned to work with the same troop units in each operation.

d. Staff planning for a joint amphibious operation should be conducted concurrently by participating staffs while assembled as indicated above. The procedure permitting maximum coordination is for the joint expeditionary force, after receipt of a directive, to make its estimate of the situation, then to issue its directive. Upon receipt of the joint expeditionary force directive, the commander of the expeditionary troops makes his estimate of the situation, and then the joint

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Figure 1.--Sequence and Coordination of Planning for an Amphibious Operation.
Figure 1. - Sequence and Coordination of Planning for an Amphibious Operation.

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expeditionary force and expeditionary troops operation plans are worked out concurrently by the two staffs. This same procedure is applicable to those subordinate echelons of the joint expeditionary force and expeditionary troops which normally work together, such as the attack force and landing force, or still lower, the transport group and the Marine division.

4. Liaison.--Liaison between the various services chosen to participate in an operation, and between subordinate and next senior headquarters, should be initiated as soon as planning starts and continued until completion of the operation. Normally, command liaison is maintained during the period that plans are being formulated; thereafter, qualified liaison officers are assigned as required. Close and intelligent liaison insures that each commander will receive early and positive information of all changes in plan or the situation, and insures that the situation confronting each echelon of command will be made known to the next higher headquarters.

 

 

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Section 2
Higher-Echelon Planning

5. Origin and Analysis of the Strategic Mission.--a. The strategic mission is determined by the joint chiefs of staff. In arriving at the strategic mission, the more important of the many influencing factors considered are:

    (1) Will the accomplishment of the proposed mission materially affect the ability of the enemy to maintain his status within the theater?

    (2) Is a well-balanced landing force of sufficient size and in a satisfactory state of readiness and training available for the task?

    (3) Is sufficient shipping available to transport and provide continuous logistic support for the landing force?

    (4) Are sufficient naval forces available to support the operation? This includes base and logistic facilities for these forces.

    (5) Is sufficient air power available, both land- and carrier-based, to support the forces involved?

    (6) Will the successful accomplishment of the proposed mission provide our forces with facilities to more advantageously conduct future offensive operations?

    (7) Is sufficient logistic support available? If any of the above factors cannot be answered affirmatively, the strategic mission must be carefully re-examined for its soundness.

b. Having decided upon the strategic mission, the joint chiefs of staff may either assign the strategic mission in general terms to the theater commander to allow him full freedom of action in translating the strategic mission into tactical plans, or they may themselves dictate to the theater commander the tactical concept of the operation. The former case is usual where only a single theater exists, but in case more than one theater exists, the proposed operation is not dependent for its success on cooperative action from, nor in any way affects the situation in, another theater. The latter case exists where the proposed operation will be participated in by forces from more than one theater and over-all direction is required to insure complete coordination.

6. Determination of Objectives.--a. The objectives to be seized in the execution of the joint chiefs of staff directive can be selected only after a thorough estimate of the situation is made by the theater commander. The objective chosen must-

    (1) Be capable of capture with forces and equipment available for the operation.

    (2) When captured, seriously interfere with the enemy's ability to continue offensive operations in the theater.

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    (3) Provide friendly forces with defensible bases, easily supplied to be used as a springboard for further offensive operations.

    (4) Be worth the losses likely to result in capturing it.

b. Once the main objective is determined by the theater commander and announced in his orders, the task force commander in turn must make an estimate of the situation to determine the order in which the various parts of the objective are to be seized. Similarly, he may determine that certain portions of the objective can be bypassed. In arriving at his decision, he is guided by the same basic considerations listed in paragraph 6a above.

7. Designation of the Task Force Commander.--a. A modern amphibious task force is composed of elements of ground, air, and naval forces acting as an integral whole. The theater commander will appoint one officer as commander of the task force in accordance with the principle of unity of command. Such a task force commander controls the various services composing the task force through their commanders, assigning them missions and permitting the subordinate commanders to work out the details of execution in accordance with the requirements and doctrines of their particular services.

b. Whether the task force commander is a ground or naval officer depends upon the nature of the operation. In the case of a shore-to-shore operation where ground forces have the paramount interest, where little opposition on the landing beaches is expected, and where the Navy has mainly a ferrying role, the task force commander properly should be a ground officer. In the case of an overseas operation where the Navy has the predominant interest, the task force commander should be a naval officer.

8. Size and Composition of the Task Force.--a. The size and composition of the task force is determined by the theater commander after a thorough study of the task to be accomplished. The main factors to be considered in this connection are:

    (1) Size of the objective or objectives to be captured.
    (2) Strength of enemy estimated to be on objectives.
    (3) Estimated reaction of hostile surface and air.
    (4) Enemy's ability to reinforce objectives.
    (5) Shipping available.
    (6) Forces available.
    (7) Estimated time required for completion of task.

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b. Consideration must be given to the fact that ground troops need to be relieved at frequent intervals during a prolonged operation. Consequently, where it is estimated that a considerable period of time will be required to complete the capture of the objective, the task force should include sufficient ground forces in its compositon to permit timely reliefs of combat units.

 

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Section 3
Planning Aids

9. Planning Schedules.--a. The time required to plan for the various phases of an amphibious operation will vary with the speed, experience, and effiiciency of the staff concerned, as well as with the size of the echelon involved. In order that the maximum use will be made of the time available to a given staff, it is desirable to prepare a planning schedule as a planning aid. Such a schedule would not only insure that each phase of the planning is completed in ample time to give lower echelons adequate time to accomplish their planning, but it also serves as a check-list which insures that nothing is overlooked. The limiting dates on this schedule should be the day the directive, or plan is received from higher headquarters and the date the command sails to rehearse the operation (S-day). The diversified nature of staffs, both naval and ground, and the inability to be certain that plans or directives will be received for planning cannot be made matters of SOP, but must be prepared by each staff as occasion requires. Experience shows that a corps can plan and rehearse for an amphibious operation in 60 days, but a minimum of 90 to 100 days is desirable. Once a directive, or plan, for an amphibious operation is received by a headquarters, the chief of staff or executive officer, as the case may be, should immediately prepare the timetable.

b. Other planning aids are maps, aerial photographs, intelligence and engineer studies, and relief models, all of which must be obtained as soon as possible after the location of the target area is learned. Vectographs and projection slides or films made of the target area are invaluable aids for briefing subordinates, and for study.

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Section 4
Intelligence

10. General.--a. Since the landing phase of an amphibious operation constitutes the commencement of a completely new campaign, and this under circumstances rendering cooperation and control difficult, the initial intelligence for such an operation must include much material not usually required for normal ground operations. This material must be in great detail to answer the needs of the ground and naval forces involved, and frequently can be obtained only by extraordinary means.

b. Continuing efforts must be made throughout the planning phase to verify or add to the intelligence available at the commencement of planning to the end that as little as possible is left to chance in the preparation and execution of the assault. As each new item or verification of old information is received at higher headquarters, this information must be disseminated at once to lower planning agencies, so that they will have sufficient time to effect necessary changes.

11. Initial Requirements.--a. Before any planning, tactical or strategic, can be undertaken for an amphibious operation, there must be complete intelligence at hand covering the area of the projected operation. Components of this intelligence which are necessary immediately for the commencement of higher-echelon planning are: (1) A study of the theater, including general information regarding geography, hydrography, climate, population, communications, public health, and customs; (2) enemy order of battle, including type, strength, location and combat efficiency of military naval, and air organizations in the area and within those areas from which reinforcement and support might reasonably come; and (3) a study of the strategic capabilities of the enemy in defending or retaining to his own use the area of projected operations.

b. While most of the material enumerated above can be provided from departmental and research sources and kept up-to-date by the employment of espionage and intercept intelligence, this is only partly true when tactical planning by assigned field forces is begun. For this part of the planning, in addition to the pertinent parts of (1) and (2) above, exact tactical disposition, defense works, and weapons of the enemy forces on the target area, and (2) the hydrographic conditions prevailing in the coastal portions of the target area.

12. Agencies Available.--a. The intelligence agencies capable of providing this tactical information are, compared with land warfare, relatively few. Among those which are available,

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aerial photographic reconnaissance is preponderant, because of the inherent nature of amphibious operations, wherein prisoners of war and documents of local tactical significance from the area to be invaded are almost never available to the attacking force before the landing. The need for secrecy of the impending invasion frequently makes it impracticable to land amphibious reconnaissance forces on an objective, especially if it is a land mass of restricted area.

b. Submarine reconnaissance is highly effective in ascertaining data with regard to surf, tides, currents, soundings, channels, and beach and shore conditions, as well as in determining ground, air, and ship traffic in and about the operations area. Periscope photographs are of great value for purposes of comparative interpretation against aerial obliques and verticals for coast defense installations, condition of beaches and slope of routes of egress therefrom, and for shoreline panoramas with which to brief naval boat-handling personnel and boat-group commanders relative to the aspect of their assigned beaches.

c. The aviation personnel involved in softening-up or photo-reconnaissance strikes should be thoroughly interrogated for their observations while flying over the objective.

d. Underwater demolition teams (UDT) are normally employed immediately prior to the landing to make a final check on the hydrographic information derived from other sources and to destroy or remove obstacles to landing. In keeping with the secrecy requirement, however, these teams cannot provide information early enough to be of use in the planning phase of the operation.

e. No effort should be spared to make the fullest use of available local experts, such as mariners or other persons who have personal or documentary information regarding sea approaches, anchorages, surf and tides, navigational obstructions, channels, and beach and shore conditions, to compensate for the attacker's normal inability to execute physical reconnaissance of the projected landing area.

f. Departmental intelligence (Joint Army-Navy Intelligence Studies, CINCPOA Studies, etc.).

g. Amphibious patrols can be of incalculable value when the size and nature of the target area permits their use.

13. Intelligence Plans.--a. It is imperative that the theater commander put into execution a detailed intelligence plan for the procurement of specifically needed information at the earliest possible moment after receipt of the mission from the joint chiefs of staff. Concurrently, subordinate planning agencies must be given all available intelligence to the end that they can plan their action at the same time. Further, the

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lower echelons should be informed of the measures being taken to implement the intelligence plan, such as scheduled photographic-reconnaissance sorties to remove the need for submission of unnecessary requests to the higher headquarters for such measures.

b. The intelligence plans of all echelons must provide for the continuous and systematic search for information throughout the period from the receipt of the mission to the consolidation of the beachhead. This provision is necessary because of the restrictions of radio silence during the voyage and the likelihood that command and control will be difficult during the landing phase until the beachhead is gained, rendering the issuance of later orders to intelligence agencies impracticable after sailing from the rehearsal area. Again, such intelligence agencies as the division or corps air observers, attached to carriers so as to be on station prior to and during the landing, cannot easily be given reconnaissance missions after sailing. Therefore, reconnaissance missions, based on a comprehensive plan, must be given to all intelligence agencies before commencement of the voyage.

c. Since aerial photographic reconnaissance is the most useful agency of amphibious intelligence, the plan normally will include the dropping of photographic sorties, taken periodically throughout the air assaults on the target upon the command ships of attack force and landing force commanders. Thus rapid interpretation will provide corroborative and new information up to the last day before landing. In this connection it should be noted that photographs should be dropped to all units to include divisions for their own interpretation, rather than forcing them to depend on joint interpretation aboard carriers concerned. This is important, for the maximum in interpretational efficiency can be obtained in a given echelon only from excellent interpreters organic within and serving as a part of that echelon. Only then do they look at the photographs through the eyes of the commander of that echelon, searching for the answers to those questions which are uppermost in the commander's mind.

d. To insure adequate and rapid fulfillment of requests for aerial photos, it is desirable to have a liaison officer from the photographic squadron stationed at the ground forces CP.

14. Security of Information.--As mentioned earlier, it is necessary at once to disseminate all pertinent and available intelligence of the enemy and the area of projected operations to lower echelons, to include landing teams and similar units. However, careful prior consideration must be given to the institution of adequate security measures to prevent leakage of information to unauthorized persons. Such measures may include the designation of a suitable space in the headquarters

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as the planning room or rooms, over which a guard is established and within which all related maps, photographs, studies, and orders are kept, and where all staff work concerned with the operation is done. Passes to the planning rooms may be provided by commanding officers, especially in higher echelons, to limit the number of members of his staff authorized to know the highly classified information involved. As the need arises, in view of lower-echelon planning, lower unit commanders and other interested officers should be given access to the necessary intelligence.

(For details of intelligence in amphibious operations, see No. 8 of this series of texts.)

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Section 5
Estimate of the Situation

15. General.--The estimate of the situation for an amphibious operation is a joint effort of both naval and ground components. Parallel echelons of naval and ground task units will make their joint estimates immediately upon receipt of directives or orders from the next higher echelon.

16. Attack Force-Landing Force Level.--The directive assigning the mission to the attack force commander will state the objective and the approximate date the landing is to take place. It will be necessary to determine the exact area of the landing and the formation of the landing forces, and the date and time of the landing.

17. Concurrent Joint Estimate.--It is mandatory that the attack force and landing force estimate be made concurrently, and it is desirable that they be made jointly. At the very least, close command liaison must be maintained during the period.

18. Responsibilities of Naval and Ground Commanders.--The landing force commander is responsible for reaching a decision as to the desired landing area, formation of troops, and time of landing. The attack force commander is responsible for determining whether the Navy can land the troops in accordance with the landing force commander's desires.

19. Adjustment of Decisions.--In the event the attack force commander decides that the Navy is incapable of executing the desires of the landing force commander, a plan is worked out between the two which is mutually satisfactory.

20. Factors of an Estimate.--Factors to be considered in making an estimate of the situation are the same as those considered in a land operation, with the following additions:

    a. Hydrography, including beaches, reefs, tides, currents, bottoms, shoals, anchorages.

    b. Availability of shipping of the necessary types.

    c. Enemy air, surface, and submarine capabilities.

    d. Beach exits.

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Section 6
Plan of Action

21. General.--As a result of their estimates of the situation, the landing force commander and attack force commander usually will arrive at two or more possible courses of action which offer good possibilities for successfully accomplishing the mission.

22. Preferred Plan.--One of the feasible courses of action will have more advantages or fewer disadvantages than any of the other possible courses of action. This course of action will become the preferred one, and a preferred plan will be prepared to place it into execution.

23. Alternate Plans.--Since plans for amphibious operations must be prepared long in advance, allowing the enemy time to change his dispositions between the time plans are set and the time the landing takes place, and since additional information will continue to come in until just prior to the landing, one set of plans will not be sufficient. Alternate plans must be made for alternate courses of action. The vagaries of meteorological and hydrographic conditions also require that alternate plans be made.

24. Selection of Alternate Plans.--The alternate courses of action will be those which are feasible, but which do not have as many advantages as the preferred course of action.

25. Form of Alternate Plans.--For each alternate course of action selected for possible execution, a complete operation plan must be prepared to avoid confusing alternate plans with the preferred plan.

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Section 7
Details of the Plan

26. Scheme of Maneuver.--a. The scheme of maneuver must aim at the early seizure of a beachhead which will cover the landing of additional troops and supplies.

b. The beachhead must include terrain which will afford observation and the opportunity to establish a base of fire for support of further offensive operations.

c. The frontage of the landing must be great enough to cause dispersion of the enemy's defensive fires, and to permit landing the maximum number of troops in as short a space of time as possible without overextension of the command and without sacrificing echelonment of reserves in depth.

d. Sufficient reserves must be withheld to allow flexibility in the scheme of maneuver, adequate protection of the flanks of the landing force, and to furnish adequate depth to the attack to permit a breakout from the beachhead if this is desired.

e. The scheme of maneuver selected must be capable of being supported by all arms and services involved. The over-all commander must take cognizance of this necessity, regardless of the branch of the service which he represents. If a naval officer is in command, he will not approve the landing force commander's recommendations unless they can be supported by naval action. If, on the other hand, a ground officer is in over-all command, he must consult the air and naval commanders involved to insure himself that the scheme of maneuver which he envisages can be supported by the air and naval arms.

27. Time of Landing.--a. Factors to be considered in selecting the time and date of landing are: weather, tides, enemy situation, and relative advantages of daylight and darkness as they affect execution of the plan.

b. The influence of weather on surf conditions and visibility must be carefully considered. High surf may interfere with landing craft operation and the unloading of transports. Fog, if long continued, may seriously interfere with navigation as well as effectiveness of supporting fires.

c. The stage and range of tides as they affect the passage of underwater obstacles, the amount of beach necessary for the troops to cross, and the ability of boats to retract, are considered.

d. Generally speaking, an enemy capable of launching air attacks on the beachhead and heavy gunfire on the transport area has the advantage if a landing is made in daylight.

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On the other hand, a landing made during darkness sacrifices accurate support by the attackers' naval gunfire support ships and aircraft.

e. A landing made at night, except to secure limited, well-defined objectives, may fail due to the probable disorganization of the landing troops.

f. It will be found advantageous in most situations to make the final approach during the early morning hours before dawn, with the actual landing being made shortly after daylight.

g. The benefits of darkness often may be obtained by the use of screening smoke, the use of which is dependent upon wind and weather conditions.

28. Ship-to-Shore.--a. One of the most critical periods of a landing is the ship-to-shore movement. Troops must be placed on the beach at the proper place, in the proper formations, and at the proper time. A failure to do this will result in dangerous gaps being left along the front of the landing, which might subject groups of the landing force to defeat in detail.

b. The plans for the ship-to-shore movement are the responsibility of the attack force commander. Details of these plans, however, must be worked out in close coordination with the landing forces, for the ship-to-shore movement must support the landing force scheme of maneuver.

29. Communication.--a. Communication plans must be worked out in great detail for the landing to insure continuous communication between all elements of the landing force during the ship-to-shore movement and during the initial stages of the landing.

b. The communication plan must be flexible enough to insure that communication is continuous, even though failures occur in some nets.

c. Naval circuits should parallel all landing force circuits at least as far as to the shore.

30. Logistics.--a. Careful planning must insure logistic support throughout the entire operation. Very flexible plans must be made to insure supply and evacuation under a series of varying circumstances.

b. The stages of logistic support may be divided as follows:

    (1) Initial supply during the period between the initial landing and the time sufficient beach area is uncovered to establish initial supplies ashore.

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    (2) The stage between the time initial beach dumps are established and transports accompanying the expedition are unloaded.

    (3) The resupply stage.

c. The amount of logistic support that can be given in any given situation must be determined early in the planning stage of an amphibious operation. Tactical plans must then stay within the scope of the logistic support that can be provided.

d. Logistic and tactical planning are conducted jointly by the theater commander and the commanders of the ground forces, naval forces, air forces, and service forces.

31. Naval Gunfire Support.--a. Details of naval gunfire support are prepared by the attack force commander; these details are based on recommendations made by the ground force commander. Naval gunfire plans should be based on a target analysis of the target area, and must fully support the ground forces projected scheme of maneuver. Plans should be made to the end that specific targets are fired upon during the preliminary bombardment and a daily check by aerial photos is made to determine which targets have been destroyed, and which need further attention. In this damage-assessment, the representatives of the ground forces and naval forces - usually the intelligence and naval gunfire officers - work jointly.

b. Naval gunfire should begin some days prior to the landing and be continuous throughout the operation as long as these fires remain effective. The length of naval gunfire preparation is governed by targets located, size of target area, and ships and ammunition available.

c. Just prior to the landing, heavy concentrations must be placed on the landing beaches, these fires shifting inland at the moment of the landing.

d. Naval gunfire is very effective in assisting in the protection of the flanks of the landing force.

32. Air Support.--a. Air support plans are prepared by higher commander in accordance with recommendations of the landing force commander. The air support, naval gunfire support, and artillery plans must be carefully coordinated, and provisions must be made for continuous coordination between these three arms throughout all stages of the operation.

33. Annexes.--a. The details of the plan are published as annexes to the operations orders. These annexes should be brief, but must include sufficient detail to insure coordination between all elements of the landing force.

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Section 8
Training

34. General.--As soon as the mission involving an amphibious operation is received by an organization and adequate intelligence regarding the hydrography, terrain, and enemy disposition is at hand, appropriate measures must be taken at the earliest practicable time to institute training for the specific type of operation contemplated.

35. Training Objectives, Land Phase.--Training directives issued in accordance with the above should contemplate the execution of training on beach area terrain and in climate similar to that known to exist in the area of projected operations. Similarly, directives must envisage special training in such operations as reduction of fortified localities, street fighting, or operations in canefields, as the case may require, to make the ground forces fully prepared for every eventuality which can be foreseen.

36. Training Objectives, Ship-to-Shore Phase.--Training for an amphibious landing always requires the orientation of fresh troops to the routines and usages of life aboard ship and the mechanics of disembarkation into landing craft in order to insure smooth functioning of both ground and naval personnel in the ship-to-shore phase. The manning of boat guns, if contemplated in the plan, must be trained for by units concerned.

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Section 9
Embarkation

37. General.--Planning for embarkation involves three principal steps. First: Allocation of transport and cargo shipping to units of the landing force. Factors to be considered in making this allocation include ship's characteristics, unit personnel and tonnage tables, and the proposed tactical employment of the units of the landing force. Second: Movement of troops and equipment to point of embarkation. This point must have adequate staging facilities for rapid and efficient embarkation. Where staging facilities are limited, plans must provide for maximum utilization of loading facilities to achieve rapid embarkation. Third: Actual embarkation by units aboard assigned ships. Plans must be detailed, and arrived at jointly by corresponding naval and military commanders.

38. Joint Planning and Liaison.--Embarkation is the first joint action of the military and naval forces in an operation. Planning for embarkation must be joint. If circumstances prevent early establishment of liaison, troop staffs must be informed of time factors involved, ship allocations, ship characteristics, and boat assistance available. At the same time, naval staffs must be furnished with unit personnel and tonnage tables and information concerning unit locations, time factors, anchorages, and harbor facilities available. Such early exchange of information assists, but does not substitute for, joint planning. Joint planning must be effected at each echelon before embarkation commences. At lower echelons, where long-range joint planning cannot be effected, tentative plans are made. These are put into effect after joint conferences of commanders and staffs are held, or after effective planning liaison is established.

39. Standing Operating Procedure.--Embarkation for participation in an amphibious operation occurs at a time when the commander and his staff are occupied with other decisions and plans. Much of the detail is common to every embarkation and can be provided for in unit standing operating procedures. In order that staffs not be unnecessarily occupied in repetitious detail, it is essential that unit standing operating procedures be promulgated before planning for embarkation begins.

40. Transport Quartermasters.--Transport quartermasters, to assist in embarkation, must be schooled and practiced in their unit standing operating procedure prior to commencement of embarkation. Sound standing operating procedures and well-trained transport quartermasters are the key to smooth embarkation.

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41. Phases of Embarkation.--Embarkation by military units for participation in an amphibious operation falls into two phases: (1) loading of equipment and supplies, and (2) embarkation of personnel. It is almost invariably desirable to reduce to a minimum the amount of time troops spend aboard ship. Planning should provide for the completion of the loading phase before personnel are embarked.

42. Plans and Orders.--Embarkation plans must be so formulated as to facilitate rapid execution of the operation plan, and are drawn up after the operation plan has been decided upon. Orders for embarkation are not included in operation or administrative orders, but are based upon them. Subordinate units receiving embarkation orders must be familiar with operation and administrative plans in order to make their own embarkation plans.

43. Control.--In order to avoid confusion and misunderstandings, embarkation plans and orders should provide for:

    a. Definite fixing of responsibility among the various commands involved.

    b. Decentralization of authority to make decisions to the echelons actually required to do the work.

    c. Positive control and coordination. This may take the form of designating a control officer in each major headquarters. Such a control officer is not charged with operating functions, but acts as an information and coordination agency.

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Section 10
Rehearsals

44. Purpose.--Complexity of amphibious operations makes it desirable that each one be rehearsed after plans and orders are completed, but before the initiation of actual operations. Such rehearsals serve a triple purpose: (1) They familiarize all personnel with the details of executing the plans; (2) they assist inexperienced personnel in becoming mentally conditioned to the shock and confusion attendant to opposed landings; (3) they reveal weaknesses of planning and execution that would otherwise remain hidden until it is too late to correct them.

44. Extent of Rehearsals.--a. While it is always desirable to rehearse amphibious operations, rehearsals may be omitted under certain circumstances such as:

    (1) Nonavailabiilty of means or time.

    (2) Need for security under circumstances in which surprise is possible, but would be sacrificed by rehearsals.

    (3) Small, simple operations in which all forces involved have a high degree of amphibious training and experience.

b. The decision to hold, or omit, a full-scale rehearsal of an amphibious operation is the responsibility of the commander of the joint forces. In lieu of a full-scale rehearsal, the joint commander may order partial rehearsals. Partial rehearsals serve to test certain units, forces, or phases of the anticipated operation.

c. Limited or partial rehearsals may also be ordered and conducted independently by subordinate commanders who have available the means and time to conduct these rehearsals. Such a partial rehearsal may embrace the entire role a particular force or unit is to play in the operation, or it may test only one phase of the operation, such as communication during ship-to-shore phase, or shore party functioning.

46. Timing.--When circumstances and security permit, two full-scale rehearsals are desirable. The first serves to familiarize all personnel with the details of execution, and to reveal weaknesses and omissions in the detailed planning. The second and final rehearsal serves to build confidence and morale among the troops preparatory to initiation of operations. The time interval between rehearsals should be sufficient to allow commanders and staffs to make necessary changes in plans and to disseminate those changes. Decisions involving changes are limited to minor improvements in detailed planning, and

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are arrived at as a result of command conferences held after the first rehearsal. These conferences are attended by commanders and staff officers of all services and forces participating in the rehearsal.

47. Plans and Orders.--a. Orders used to initiate rehearsals normally are issued after all or almost all of the operation and administrative plans are promulgated. In such cases, rehersal orders are brief. They refer to the applicable operation plans and annexes, define the objective and extent of the rehearsal, specify those items in which rehearsal procedure is to vary from actual operation procedure, and provide for those administrative details attendant to the conduct of the rehearsal.

b. If rehearsal orders are issued prior to promulgation of the operation and administrative plans, they must be in great detail. For that portion of the operation which is to be rehearsed, rehearsal orders must be as complete and in the same form as the contemplated operation and administrative orders.

c. If the conduct of the rehearsal presents an opportunity to compromise the secrecy of contemplated operations, the rehearsal order should be divorced from the operation plan for security reasons. In such a case, the order for the rehearsal must be complete without reference to the operation plan or to the scene of operations. Within these limitations, the rehearsal plan affords the maximum possible realism and resemblance to the projected scene of operations and scheme of maneuver.

48. Replacement of Losses.--Conduct of rehearsal inevitably results in certain losses of personnel and equipment and expenditure of supplies and munitions. These losses and expenditures should be anticipated by the echelon ordering the conduct of the rehearsal. That headquarters makes plans and takes positive steps to replace such losses prior to initiation of operations.

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Section 11
Shore-to-Shore

49. Definition.--Amphibious operations in which the troops land directly on the hostile shore from the same vessel, or landing craft, in which they embarked and made the water voyage are known as shore-to-shore operations. In such operations the point at which the troops embark is referred to as the near shore. The point at which they land is called the far shore.

50. General.--In most respects, shore-to-shore operations are very similar to the more usual ship-to-shore amphibious operations. Specifically, they require a condition of friendly air and naval superiority. Landings must be supported by adequate naval and air bombardment. In such matters as selection of beaches, scheme of maneuver ashore, and communication, shore-to-shore operations are no different than other amphibious operations.

51. Characteristics.--In other respects, shore-to-shore operations assume special characteristics which must be considered in planning.

a. Landing craft, rather than ships, are employed to transport and land troops and matériel. Because of this feature: -

    (1) Distances over which operations can be launched are sharply limited.

    (2) The effect upon troops of long voyages is to reduce their initial combat efficiency.

    (3) Shore-to-shore operations are greatly affected by weather and sea conditions.

    (4) Flexibility in concentrating and moving reserves and supplies exceed those in ship-to-shore operations.

b. In shore-to-shore operations, the far shore (point of landing attack) is much closer to the mounting-out point than in ship-to-shore operations. Because of this difference: -

    (1) The initial landing can be made with fewer reserves and supplies. Short round-trip and turn-around time for landing craft in the initial landing permits rapid resupply and reinforcement.

    (2) Under certain circumstances, the landing force may land and operate within supporting distance of friendly units already established ashore.

c. Because of their special characteritstics, shore-to-shore operations can be planned in less time than can ship-to-shore operations. Embarkation is also accomplished more quickly.

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52. Logistic Support.--Upon completion of embarkation, an authority and organization must be established or left at the near shore for the purpose of rendering logistic support to the operation. This organization must include personnel and facilities for assembling, loading, and dispatching resupply and maintenance items. It also must be equipped to maintain and service landing craft employed in resupplying the landing force. The officer at the near shore who is responsible for logistic support should have, on his staff, a representative of the over-all landing craft force commander, who assists in proper utilization of those landing craft.

14219 MCS Quantico, Va. 9-14-45--1700

 

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