Chapter 3
Landing Boats

		Paragraphs
Section I.	General	58-65
II.	Standard Army and Navy boats	66-73

Section I
General

58. Boat Requirements.--

    1. Successful landing against opposition requires boats in adequate numbers and with suitable characteristics to land the personnel and matériel of the Army forces in accordance with the tactical and administrative plans. The Navy is charged with providing and operating these boats. The detailed information needed by the Navy to determine the requirements in landing boats is furnished by the Army in the embarkation and debarkation tables, with their appendices. Basic data are developed from the joint plan of the Army and Navy commanders designated for the expeditionary force (see chs. 5 and 10).

    2. It is desirable to land all combat troops in one trip. With large forces this is not practicable. The number of boats provided should at least permit the landing in the first trip of the assault combat teams and local reserves required to gain and to hold the first objective until additional troops are landed.

59. For Assault Combat Teams.--It is desirable that the assault combat teams be landed in boats capable of producing a heavy volume of fire, armored to give protection against small-arms fire, and having high speed and shallow draft.

60. Size.--

    1. The use of relatively small boats in landing the leading echelons has advantages, namely:

       1. A heavy volume of fire can be delivered upon approaching the shore.

       2. Landing can be made near the shore.

       3. Troops can be disembarked quickly and deployed promptly for attack.

4. Small boats present a less concentrated target.

5. Can be carried in spaces not otherwise used and on vessels not equipped with large capacity booms.
2. Figure 2 illustrates some of the advantages of small boats over large boats in leading waves. Company A, on the right, lands its leading wave in eight small shallow draft boats. The boats run well in to the beach and troops are on shore without delay. Troops deploy ashore with slight lateral movement. The enemy fire is dispersed over eight targets, and a relatively small number of men are exposed to a single shell, mine, or the beaten zone of a machine gun. Company B lands its leading wave in one large boat. this boat beaches relatively far out, has less firepower, enemy fire can be concentrated, and troops must move laterally to get into attack formation. For example, the flank squads of Company B have to debark and move 200 yards directly by the flank under enemy fire to reach their proper place in formation.
   
   Figure 2.--Comparison of small and large boats in landing leading subwave.

3. Large boats, however, have certain advantages, particularly for rear waves. To land a given number of men requires fewer boats, less stowage space aboard ship, and fewer boat crews. Large boats simplify and speed the execution of the ship-to-shore movement, particularly where the beach or approach thereto is restricted. They can be used to best advantage where, due to surprise or under protection of troops already landed, the boats and troops disembarking will not be subjected to aimed fire of small-arms or antiboat guns.

4. Based upon tactical employment, procurement, and transportation, it will usually be advisable for each boat group to contain boats of several sizes. The most suitable sizes are boats with a capacity of--

   1. From 12 to 25 fully equipped soldiers, in addition to the crew, for landing the leading waves.

   2. 20 to 40 soldiers for landing support echelons.

   3. 40 or more soldiers for landing reserve echelons.
61. Speed.--Fast boats are less vulnerable to enemy fire, reduce the time available to the enemy to concentrate his troops and perfect his defensive measures, and decrease the interval between the lifting of the naval supporting fire and the arrival of the boats at the beach. Since the enemy may be expected to man his defenses near the beach upon the lifting of the supporting fire, any decrease in this interval enhances the assaulting combat team's chances for success.

62. Armament.--To compensate for the limitations of naval gunfire and the necessity of lifting this fire when boats are still well off the beach, each boat of the leading wave should be heavily armed with machine guns, 37-mm guns, or other suitable weapons, mounted for rapid and accurate laying from a moving platform. Owing to their ease of landing, rapid fire, and usefulness as antiaircraft weapons, a large percentage of the boats should be equipped with machine guns, including submachine guns. The effectiveness of the fire from boat guns will vary materially, depending upon the training and experience of the personnel.

63. Draft.--Light draft boats are preferable for leading echelons. The light type boats not only can proceed closer to the beach but also can be extricated more easily and rapidly under their own power after grounding or beaching. Boats with heavy draft will ground a considerable distance offshore, causing troops to disembark in water above their waists and struggle ashore under severe handicap. This difficulty is accentuated on gently shelving beaches where the boats ground an appreciable distance offshore, and on beaches where the boats ground on a bar with deeper water between the bar and the shore. troops wading ashore receive limited support by gunfire during this period, movement is slow, and equipment is handled with difficulty. Under such conditions heavy

casualties against even slight enemy opposition may be anticipated.
64. Reserves.--Boats with large capacity are preferred for transporting reserve battalions which are landed under the protection of other troops. Standard Navy motor launches or boats of larger capacity may be used for this purpose. Where it is necessary to land reserve battalions in the second trip of the boats, the movement can be expedited by embarking the reserves on destroyers or other small craft which are moved as close to the beach as safety permits.

65. Lighters and barges.--

    1. The landing of heavy artillery requires especially adapted lighters. Such lighters must have the necessary capacity with comparatively shallow draft. They should be able to run well up on the beach and permit unloading of guns by ramps between lighter and shore. These lighters can also be used for the landing of other vehicles, airplanes, and heavy matériel, as well as supplies in large quantities.

    2. Self-propelled lighters capable of carrying and debarking available amphibian tanks or of landing light tanks with or ahead of the leading waves are desirable. The lighters should be of shallow draft and permit nonamphibian tanks being run ashore without delay under their own power. The lighter should be heavily armed in order to provide a point of support on the beach and cover the landing of the tank.

    3. lighters capable of transporting guns and other heavy matériel can be improvised by building a platform over two standard 50-foot motor launches. li> Water barges may be required for the delivery of water in bulk to the beach during the later phase of landing.

Section II
Standard Army and Navy Boats

66. General.--Standard Navy boats, while not well suited for a landing against opposition, constitute the principal source of boat procurement and, because of their availability, are used. they are suitable for landing reserves and supplies when the beach is fairly well protected from enemy fire or when the landing is lightly opposed. The Army 36-foot Higgins

boat and the 45-foot tank lighters carry armor plate, sufficient to protect the boat crews and other personnel against small-arms fire.
67. Table of Characteristics.--Characteristics of standard Army and Navy boats are shown in the tables below. The explanation given in the paragraphs which follow should be considered when using the data given in the tables.

68. Capacity in Boat Spaces.--

    1. Referring to column 2 of the table, "boat space" is a term employed to indicate the space and weight required for one soldier with his individual equipment. A solder so equipped is assumed to weight 224 pounds (¹/10 of a long ton) and to occupy 13.5 cubic feet of space.

    2. Boat spaces available for troops or matériel are computed as 60 percent of the rated maximum personnel capacity of the boat, less the number of men in the crew. This loading is approximately 80 percent of the maximum capacity of the boat by weight.

    3. Boats are not filled to capacity under adverse conditions of weather, sea, or surf. If under fire, there should be room to keep troops low in the boat. If weapons are to be fired from the boat, space is allowed for their operation.

Standard Army Boats

1	2	3	4		5	6	7
Type	Boat spaces (in addition to minimum crew)	Speed (miles per hour)	Time to load (minutes)		Minimum crew	Mean draft loaded (approx- imate)	Weight (approx- imate)1
			Day	Night
						Ft. In.
Higgins boat, 36-foot	86	10	6	8	4	2   9	16,534
Navy launch, 40-foot	36		8	10	3	2 10	9,800
Gasoline		10
Diesel		143/4
Tank lighter, 45-foot	(2)	10			6	2 10	50,500

1 Includes hull, engines, standard equipment, and fuel.
2 1 tank (27,000 pounds).

Standard Navy Boats

1	2	3	4		5	6	7	8
Type	Boat spaces (in addition to minimum crew)	Speed (knots)	Time to load (minutes)		Desig- nating letter	Mini- mum crew	Mean draft loaded (approx- imate)	Weight (approx- imate)1
			Day	Night
Motor launch							Ft. In.
50-foot	110	7	15	20	A	4	3 1	21,400
40-foot	50	6	8	10	B	4	2 5	14,500
36-foot	38	6	6	8	C	4	2 2	11,100
33-foot	27	4	5	7	D	3	2 2	8,400
30-foot	21	5	4	6	E	3	2 2	8,400
24-foot	10	5	3	4	F	2	1 11	5,600
Motorboat:
50-foot	25	10	5	7	I	4	3 1	19,500
40-foot	18	9	4	6	K	4	2 8	15,000
35-foot	12	8	3	4	L	4	2 9	13,600
26-foot	8	6	3	4	M	3	2 1	6,200
Motor whaleboat,2 26-foot	11	51/2	3	4	N	3	2 1	5,300
Whaleboat:
30-foot	22	(3)	4	6	O	2	1 9	3,300
28-foot	17	(3)	4	6	P	2	1 8	2,900
24-foot	12	(3)	3	4	Q	2	1 7	2,300
Dinghy:
20-foot	7	(3)	3	4	R	1		1,200
16-foot	5	(3)	3	4	S	1		700
Wherry:
14-foot	3	(3)	3	4	T	1		600
12-foot	2	(3)	3	4	U	1		400

1 Includes hull, Diesel engine, standard equipment, and fuel.
2 Unsuited for landings in heavy or even moderate seas.
3 Pulling boat; must be towed.

4. Consideration is given to the dimensions of each vehicle and to the height of the center of gravity of the load as they affect stability afloat. For example, only one tractor and two trailers requiring (together with boat rig A) by weight 71 boat spaces can be loaded in a 50-foot motor launch which has a rated capacity of 110 boat spaces (see par. 73). The remaining capacity can be utilized for personnel or general cargo.

5. The space and weight of any protective armor, boat guns and ammunition, and extra anchors reduces the capacity of a boat.

6. The capacity of a boat in tons is one-tenth of its rated capacity in boat spaces.

7. In planning landing operations, tables are prepared showing the boat spaces for Army equipment. The following examples are from Navy tables for Navy boats:

   Ammunition, 100 rounds, 75-mm pack howitzer, H.E. boxed (4 rounds per box)	11.4
   Boat rig A and ramp	34.0
   Container, water, 10-gallon, filled	.5
   Caisson, ammunition, 75-mm gun, with load	15.0
   Car, cross-country, empty	12.0
   Gasoline, 1 case of two 5-gallon cans	.4
   Gun, 75-mm	12.0
   Motorcycle, with side car	5.0
   Rations (1 day for 100 men)	2.5
   Reel, wire, hand	2.0
   Truck, light, 1/2-ton, empty	10.0
   Truck, light, 11/2-ton, with load	28.0

69. Speed.--The speeds (in miles per hour for Army boats and knots for Navy boats) indicated in column 3 of the tables are average speeds with loaded boats, engines in good order and fairly smooth water. Speeds will vary and should be determined by actual tests under various conditions of weather, sea, and load. The speed of a boat used in towing is cut approximately 50 percent when the combined load of the boats in tow equals the rated capacity of the towing boat.

70. Time to Load.--The loading times in the tables are based upon debarking under average conditions, using cargo nets over the side of the transports in place of ladders and gangways. An allowance of about 50 percent has been made for delays which are expected under war conditions. the time given includes delays incident to placing the boat alongside transports. The time of loading a boat will carry according to the relative amount of personnel and matériel comprising the load, the facilities of the transport for discharging, the training of the personnel, and the condition of the sea.

The loading time for each boat should therefore be determined by tests conducted under various conditions, using the actual load to be transported by the boat.
71. Designating Letters.--In boat diagrams and orders relative to debarkation it is convenient to designate each type of boat by a letter, using the designating letters listed in column 5 for Navy boats. For example, the designation "A-1" is used instead of "50-foot motor launch No. 1." These designating letters are placed on the boat. Similar procedure is advisable for Army boats.

72. Crew.--

    1. The figures shown in column 5 for Army boats and column 6 for Navy boats indicate the minimum number of men required to handle the boat. The figures do not include boat officers, gunners, additional personnel for handling lines, signalmen, or hospital corps men for ambulance boats. Army personnel to be landed may be used as gunners. Members of the beach party can be detailed to duty such as boat officers and linesmen. The number of additional officers and men is determined for any particular situation, and the number of boat spaces shown in column 2 of the tables is reduced accordingly.

    2. the exact strength of the crew and other Navy personnel that will embark in each boat must be determined early. This information is furnished the landing force commander before the boat assignment tables are initiated.

73. Boat Rig and ramp.--

    1. For landing tractors, trailers, trucks, light artillery, and other vehicles from standard 50-foot motor launches, the Navy provides a special boat rig (boat rig A) and ramp (see figs. 3 and 4). Boat rig A consists of a wooden platform and runway to the bow, the necessary support therefor, and the gear for securing the ramp to the bow. The rig weighs about 4,700 pounds (not including the weight of the ramp) which reduces the capacity of the boat accordingly.

    2. The rig is designed to fit a 50-foot motor launch, without modification of either boat or ramp. Because of variation in design of 50-foot motor launches in service, minor alterations are sometimes necessary to fit the rig. After fit has been assured, the rig can be installed before lowering or when the boat is alongside in about 30 minutes.

Figure 3.--Boat rig A installed in 50-foot motor launch.

Figure 4.--Unloading tractors from 50-foot motor launch equipped with boat rig A and ramp.

3. The ramp is pivoted at the bow of the boat, permitting both vertical and lateral movement. the shore end of the ramp is fitted with two rounded bearing lugs which ride in the grooves of angle irons laid on the bottom, permitting a free fore-and-aft movement of about 6 feet. The ramp is carried disassembled in the boat. The heaviest piece weighs 260 pounds, and the total weight of the ramp is 2,800 pounds. Upon arrival at the beach the ramp can be assembled and made ready for use by 8 men in about 10 minutes.

4. When the boat is unloaded and it is intended that repeated landings at the same place will be made, the ramp may be left assembled on the beach. In this case, the same ramp may be used for unloading several boats, reducing the relative number of ramps that will be required at this landing beach. An assembled ramp can be connected to an incoming boat in about 5 minutes.

5. Upon favorable conditions, vehicles up to 5-ton weight can be landed from standard 50-foot motor launches by means of boat rig A and ramp. After the ramp is connected, about 1 minute is required to land a tractor and two trailers.

6. A disadvantage of this rig is the relatively high center of gravity of the boat with a vehicle load, limiting or precluding its use under adverse conditions of weather, sea, or surf. Ammunition, rations, or other heavy matériel should be loaded in the boat to provide ballast when boat is used for vehicles.

7. Special type lighters, especially artillery lighters and the 45-foot tank lighter, are preferable to boat rig A.

8. The Army 45-foot tank lighter carries already installed equipment similar to the Navy rig which must be fitted to the 50-foot Navy launch. The Army tank lighter is designed to carry one light tank with its crew and equipment.

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