Supply, Movements and Evacuation
1. OUTLINE OF SYSTEM OF SUPPLY. a. General. (1) The executive control required for maintaining a force in the field is provided by the services, under the supervision and direction of both the Administrative Staff and the Transportation Section (or Department) of the General Staff. The Chief of the General Staff is responsible for planning and policies, and the Transportation and Communications Bureau of the General Staff is responsible for the technical details of both land and sea transportation to implement the Chief of the General Staff's plans.
Section I. SUPPLY
(2) The services--intendance, ordnance, medical, and veterinary--each have their respective bureaus (Directorates) in the Ministry of War, and are represented by their staffs on the lines of communication, army, division, and unit headquarters.
(3) In the Japanese Army, the Intendance Bureau in the Ministry of War is responsible for the supply and maintenance of provisions (rations and forage) , equipment (clothing etc.) , and pay; the Ordnance Bureau, for the supply and maintenance of arms, ammunition, engineer and transport equipment. The transportation of supplies, except within the forward units, is controlled by the Transportation Section of the General Staff. The transport of supplies within the forward units themselves is undertaken by the transport regiments and the various trains, such as the regimental and battalion trains.
(4) Variety in means of transportation is a characteristic of the Japanese Army; animal transport is largely used, and the most commonly employed vehicle is a 2-wheeled cart with a carrying capacity of 400 to 500 pounds. In mountainous country or places where roads are absent, pack horses are frequently used. In jungle terrain, the use of porters is common. Throughout the island areas of the Southwest Pacific barges and small craft are extensively employed. Motor transport is found where roads are available, though its exclusive use anywhere is exceptional.
b. Functions of lines-of-communications units. (1) The line-of-communications units establish and maintain a series of supply and evacuation centers along a main supply line (road, rail or waterway) extending from the communication zone, (or from the base ports of an oversea force), forward into the areas of the front-line divisions. Their general functions are--
(a) To establish depots, where required, for the handling of all classes of supplies.
(b) To receive, stage, ration, and forward men and animal replacements.
(c) To receive, store, and forward supplies.
(d) To evacuate casualties, prisoners of war, surplus supplies, salvage, and captured equipment.
(e) To provide medical and veterinary service for transients.
(f) To assess local supply resources and to requisition them as required.
(g) To provide local defense of line-of-communications establishments.
(2) The layout of a line-of-communications system is shown in figure 150. It will be noted that supplies may be passed direct from the base to the field-maintenance center (sea, road or rail-head) , or an advanced base may be interposed when the line of communications is long and liable to interruption; also that the introduction of supply relay points is dependent upon the necessity for changing the type or method of transportation between various delivery centers.
c. Line-of-communications headquarters, depots and units. (For more detailed organization see chapter III.)
(1) Line-of-communications headquarters. The headquarters administers the line of communications and its branches as ordered by the army line-of-communications command. It is able to provide up to 14 line-of-communications branches (garrison or sector units) .
(2) Line-of-communications garrison (or sector) units. Branches are formed in order to decentralize the administration on a long line of communications. The number required will depend on the distance from the base of the force being supplied. Each branch will be given its own headquarters and signal communications and includes a combat defense force.
(3) Line-of-communications signal units. Usually there are two or more companies, the personnel of which are allotted to the line-of-communications headquarters and branches.
(4) Combat units in reserve. Used to provide local protection and escorts as required along the line of communications.
(5) Transportation units. (a) Line-of-communications transport units--land.
- Line-of-communications transport headquarters, also referred to as field Transport Headquarters or commands, administer several transport regiments and several transport supervision detachments.
- Independent transport companies (drafthorse transport). Each company has a carrying capacity of about 60 tons and a strength of about 350 men. They are attached on the approximate scale of 4 per division with a variable number for army troops.
- Independent transport companies (motortransport). Each company has approximately the same carrying capacity as a wagon company and a strength of about 200 men. They are attached on the scale of 1 per division with a variable number for army troops.
- Independent transport companies (packhorse transport). When necessitated by the terrain, pack-horse companies are employed. The carrying capacity of two pack-horse companies equals that of one wagon company.
- Provisional transport units. These areengaged in transporting food, supplies, and ammunition to line-of-communications dumps but may be attached to armies or divisions. In the Southwest Pacific Area many of these units are formed as required and often have to operate without motor transport or horses. Each unit contains from 200 to 800 men.
- Line-of-communications transport-supervision detachment (transport escort--port facilities. A transport-supervision detachment, with a strength of about 200, may operate 6 or 7 locally-formed transport companies.
- Railway units (railway commands, railway regiments, armored train units, etc.)
- Tractor units.
(b) Line-of-communications transport units (sea).
- Shipping headquarters. All water transport is under the Shipping Headquarters, a branch of the Transport Section of the General Staff. The headquarters is located at Ujina, a port near Hiroshima in Japan, and allocates, as well as commands the various units necessary for the preparation of transport vessels and the actual operation of sea transportation. The following units are under its command:
Shipping transport headquarters (or commands).
Shipping transport area headquarters.
Shipping transport battalions.
- Shipping groups. These branch offices,established by the Shipping-Transport Headquarters, are located at the principal base ports--Singapore, Manila, and Rabaul--in theaters of operations. They control a variable number of Shipping engineer regiments and debarkation units.
- Shipping Engineer regiments. These units are used for getting troops and supplies ashore, particularly in landing operations. They operate barges, speed boats, armored craft, etc., and man the craft on coastal and inter-island runs. Strength is approximately 1,100 men with about 150 assorted small crafts.
- Debarkation units. The functions of these units are vague. They would appear to be responsible for the actual unloading and landing of troops and supplies on and from the transports to the small craft operated by the shipping engineers, when no anchorage unit is present as in the case of landing operations. Strength is approximately 1,000 men.
- Shipping transport headquarters (or command). These are directly responsible to the shipping headquarters at Ujina. Shipping transport headquarters are located at the principal base ports where they are responsible for the required installations such as wharves and warehouses, the fueling and provisioning of ships, the storage of cargoes (exclusive of unit equipment) , and the planning and writing of sea transport in conjunction with the Navy. They also supervise the embarkation of troops.
- Shipping transport area units. These units control shipping ordnance, antiaircraft artillery, and signal troops detachments of which are assigned for the defence and armament of shipping and for intercommunication within and from convoys on transports.
- Anchorage. These units are port administrative organizations. They are located at the principal base ports as well as at the smaller bases. In addition, they may establish branches at small subsidiary bases. Anchorages are composed of a variable number of so-called Land Duty, Sea Duty and Construction Duty Companies.
- Land duty companies. These are stevedore companies of approximately 350 men.
- Sea duty companies. These are barge and lighter operating units of approximately the same strength as the Land Duty Company.
- Construction duty companies. These are used for general construction work, such as roads, warehouses, etc.
- As there might appear some confusion between the duties of Debarkation Units and Anchorages, it is well to remember that the former are responsible for getting troops ashore in actual landing operations where port facilities may be non-existent, whereas the latter function in established areas. 6. Shipping transport battalions. It is assumed that these units are responsible for the operation of small craft, other than those operated by the shipping engineers.
(6) Ordnance units. (a) Field ordnance depots. These depots stock, issue, and repair ordnance equipment and supplies other than ammunition, motor transport, and air stores, and collect and dispose of ordnance salvage. A depot is able to provide 2 branch depots and 4 advanced sections, and may have 4 mobile repair sections attached. Branch depots are installed at field maintenance centers (sea, road, or rail-heads) and at advanced bases during temporary maintenance stage. On a line of communications for a single division, a field ordnance depot combines the functions of the field ordnance depot and the field ammunition depot. In this case it is able to provide one advanced section and one mobile repair section.
(b) Field ammunition depots. These depots stock, issue and repair all types of ammunition, chemical warfare equipment, and salvage. A depot is able to provide 2 branch depots and 4 advanced sections. Branch depots are installed similarly to the Field Ordnance Branch Depots.
(c) Field motor-transport depots. Furnishes and maintains motor transport.
(d) Field shipping ordnance depots. See under "Shipping Transport Area Units."
(7) Intendance units. (a) Field freight (supply) depots. Also known as Field Clothing and Ration Depots, they stock and issue rations, forage, canteen supplies, clothing, etc., and make, repair, and sterilize clothing. They collect and dispose of the same type of salvage. A depot is able to provide two branch depots and four advanced sections and may have 4 mobile clothing repair sections attached. Branch depots are installed similarly to the field ordnance branch depots. On a line of communications for a single division a field supply depot includes the functions of a field medical supply depot. It is able to provide one advanced section, and may have one mobile clothing repair section attached.
(b) Pay. The Intendance Service is responsible for the pay and accounts of the Army.
(8) Engineer units.
Engineer stores depot.
Field road construction unit.
Field construction units.
Field fortification units.
Field water supply units.
Labor and carrier units.
Field military police units.
Personnel for staging camps.
Personnel for labor camps.
(10) Army Air Force.
Field air depot.
Field air repair depot.
Horse purchasing depot.
Field remount depot.
(12) Medical and Veterinary. (a) Line-of-communications Hospitals and field reserve hospitals. These have a capacity for 500-1,000 patients each. If necessary each type of hospitals can be divided into two hospitals.
(b) Line-of-communications Veterinary Depots. These have a capacity for 700 horses.
(c) Field Medical Supply Depots. These stores, issue and repair medical supplies, patients' clothing, veterinary supplies and horse shoes. A depot is able to provide two branch depots and four advanced sections. The branch depots are usually installed similarly to the Field Supply Branch Depots. On a line of communications for a single division, the field supply depot may combine the functions of the field supply depot and the field medical supply depot.
(d) Casualty Clearing Stations.
(e) Ambulance Transport Units.
(f) Field quarantine department.
(g) Veterinary quarantine hospital.
d. Maintenance of line of communications (see fig. 150). (1) General. The supply columns of a line of communications are organized, oaded and dispatched from the base area of the base depots. The base area is seldom moved; however, an advanced base may be interposed when the line of communications is long or liable to interruption. The forward terminal of a line of communications is the point where the units transfer their supplies to the divisions transport regiments. The forward terminal is kept as close as possible to the front line and may be either the Division Maintenance Center (the more normal) or the Field Maintenance Center, whichever is the more accessible.
(2) Maintenance terminals on the line of communications. (a) Advanced base (see figures 150 and 152). The establishment of an advanced base will depend on the maintenance requirements
Figure 150. Japanese supply system and layout of lines of communications.
Figure 151. Field Maintenance Center (sea-, road-, or rail-head).
of the supported force; the length of the line of communications, the possibility of enemy interference, and climatic conditions. Advanced depots of the base installations are usually represented at the advanced base.
(b) Supply Relay Points (see figures 150 and 152). These points are established on the line of communications as required. The organization of each will depend on its location on the line of communications and the weight of traffic to be handled. Relay points are maintained for reloading and dumping supplies, as staging points for transients, and as terminals and technical maintenance points for transport echelons.
(c) Field Maintenance Centers (see figures 151 and 153). These are also referred to as either Sea, Road or Railheads. Their size and organization will depend upon the size of the force being maintained, and the extent to which reserve stocks must be held in the area. Main service depots will be normally represented here by their branch depots or their advanced sections.
(d) Division Maintenance Centers (see figure 150). With the division administrative area are located ordnance and supply depots under the control of the division administrative staff.
e. Operation of line-of-communications supply system (see figure 150). Supplies are shuttled between Relay Points, Division Maintenance Center and from the Field Maintenance Center in one of three ways, depending on the distance between each.
(1) A loaded supply column moves forward from the supply Relay Point next closest to the Division Maintenance Center, unloads its supplies, and returns empty to the Relay Point for reloading.
(2) A Supply Column moves empty from one Relay Point to the Relay Point nearest to the Field Maintenance Center (assuming more than one Relay Point is established between the Divisional Maintenance Center and the Field Maintenance Center) loads and returns to its original Relay Point for unloading.
(3) (a) A loaded supply column moves from the Field Maintenance Center directly to the Divisional
Maintenance Center, by-passing the Relay Points, if any. This method is considered to be the most expeditious.
(b) When the rate of advance of the force being supplied necessitates a forward movement of the depots, this is generally done by pushing forward a branch or advanced section of the main depot and after the forward branch has been established and functioning, the balance of the depot will be moved up.
(c) Supply Relay Points are introduced when the type and method of transportation between delivery points or terminals must be changed, or when reserves must be held in the rear of the Field Maintenance Center but forward of the Base or Advanced Base and between Divisional Maintenance Center and Field Maintenance Center. For example, during the Japanese occupation of Guadalcanal, in 1942, the advanced base was Rabaul and a relay point was established on Shortland Island. The Field Maintenance Center was on the northwest coast of Guadalcanal. Supplies were delivered from the advanced base or direct from Japan to either the relay point or the Field Maintenance Center. The size of theforce, the nature of the campaign, the quantity of stores to be held in reserve, and the extent to which permanent maintenance has replaced temporary maintenance will modify the layout of the line of communications. Thus at one stage the Division Maintenance Center may operate at the Field Maintenance Center, supplied direct from base or advanced base. Then as the force advances, the Division Maintenance Center may move forward, and the Field Maintenance Center may be developed as an advanced base.
2. SUPPLY IN THE FIELD. a. Maintenance requirements. (1) There are few or no figures available (except on rations) which indicate the exact maintenance requirements of the Japanese soldier in the field. As in all Armies, maintenance requirements will vary depending on the theater of operations. It is generally accepted that the daily requirements of the Japanese soldier are considerably less than for soldiers of the Allied Forces.
(2) Ration and ammunition may be considered the principal items of daily requirements. The weight of the Japanese ration (except emergency
Figure 152. Japanese advanced base served by a railway system.
Figure 153. Supply Relay Point.
ration) is approximately two-thirds that of the American ration, or slightly above 4 pounds. Ammunition requirement is also smaller due to less employment of artillery by the Japanese, however, it is worthy of note, that the Japanese estimate as high as 4.2 pounds a day per man for active operation, compared with 5.17 pounds for United States forces. In the southwest Pacific Area, the daily ammunition requirement of the Japanese has been estimated by Allied Forces to be as low as 1 pound a day.
(3) As to other items of maintenance requirements, there is no agreement as to the exact amounts required. In the absence of detailed information no definite amount can be stated, but in making an estimate it is well to keep in mind that there is no substitute for many of the daily requirements and in the absence thereof, the ability to fight is considerably curtailed. For example, without fuel the Japanese cannot operate. The item of fuel is given as an illustration to show that while the individual soldier may be able to live for awhile on emergency rations, he cannot survive unless other necessary supplies are brought. Any estimate which leaves out fuel is therefore likely to be erroneous. While allowing for variation in need, it should be remembered that there are many irreducible requirements in operation. Roads cannot be used, ordinarily,without repair and the poorer the road the greater the need for repair. Likewise medical attention cannot be neglected if health is to be maintained. The Japanese realize the necessity of meeting daily requirements and their doctrine states that it is well to establish Advanced Supply Bases wherever possible.
(4) To summarize while no definite figures can be given at this time for daily requirements, due consideration should be given to all essential items when an estimate is attempted. The daily maintenance requirements have been roughly estimated from 10 lbs. to over 30 lbs. a day per man, depending on the operation and availability of local supplies.
b. Rations and forage. (1) Garrison. In garrison the Japanese ration consists of about 1.25 pounds of rice and a certain amount of barley plus a cash allowance which is made for each soldier to be spent on the purchases of meat, fish, and vegetables. This ration is both varied and adequate. On maneuvers rations are somewhat increased. The following are common constituents of the purchased ration:
(a) Cereals and staples. Rice, wheat, barley, canned rice cakes, canned powdered rice dumplings,
canned rice boiled together with red beans, biscuits, hardtack, vitamin biscuits, sugar, soy bean flour.
(b) Canned meat and seafood. Beef, salmon, sardines, mackerel, seaweed, clams, trout, tuna fish, cod livers, seaweed and beans packed in layers, crab meat.
(c) Dried meat and fish. Flounder, salmon, bonito, squid, cuttlefish, laver meat.
(d) Canned fruits and vegetables. Tangerines, pineapples, bamboo sprouts, bean and burdock, boiled lotus root, sprouted beans, arum root paste, spinach, mushrooms, beanflower, mixed vegetables, carrots.
(e) Vegetables and fish in barrels. Pickled salted plums, pickled radishes, sea cucumbers in curry powder, smelts in oil.
(f) Dried fruit and vegetables. Apples, carrots, Chinese greens, red beans, onions, potato chips, mushrooms, squash, kelp.
(g) Seasonings, etc. Soy bean sauce, dehydrated soy bean sauce, soy bean paste, vinegar, curry powder, salt, ginger.
(h) Beverages. Tea, sake, condensed milk.
(2) Field. (a) Rations and forage supplies in the field may be both "imported" or "local." The former are manufactured and purchased by base supply depots operated by the Intendance Bureau in Japan. The latter are obtained by purchase, requisition, or confiscation. The field ration in the Japanese Army is fixed by regulation as consisting of the following:
- Standard, or normal field ration (total,about 41/8 pounds), consisting largely of rice and barley, fresh meat and fish, fresh vegetables, and various condiments and flavorings.
- Special field ration (total, 3 pounds),consisting largely of rice, dried, canned, or pickled items. This ration is the one most likely issued in combat.
- Reserve (emergency) ration: Class A(total, 21/4 pounds) consisting of rice, canned meat, and salt; Class B (total,13/4 pounds) consisting of rice or hardtack, canned meat, and salt.
- Iron rations, weighing about one-halfpound for one meal, include special Japanese biscuits and extracts that have been successfully tried out in various climates.
- Nutritious rations, consisting of extraamounts of all kinds of food are allowed to men who need them.
- Substitute items according to a regularsystem.
- Supplementary articles, to be issued asavailable, consisting of cigarettes, either sake or sweets.
(b) There are indications that the average ration in active theaters is about 31/2 pounds, and thatbecause of failure of supply, this ration has often been reduced to a half or third of the normal amount. The Japanese use local provisions whenever possible and encourage the local cultivation of vegetables by units. Vitamin pills are a part of the regular issue, and delicacies, especially canned fruits, are issued occasionally.
Type Item Standard ration Special ration Reserve emergency ration Cereal Rice 23.3 20.5 30.7(A) Barley 7.4 Hardtack 8.1 24.4(B) Meat Fresh Canned (5.3) (5.3) (5.3) Dried (2.1) 2.1 2.1 Vegetable Fresh 21.2 Dried 4.2 Pickles Vegetables, etc 2.1 1.8 Condiments Salt .18 .18 .18 Sugar .7 .7 .35 Flavoring Soy 1.4 1.1 1.1 Bean paste (2.6) 1.1 Extras Tea .11 .11 Sweets (4.2) Sake 2.4 Cigarettes 120 120 Total 364/69 340/45 4
Fuel: 2.8 oz per man.
Water (drinking and cooking) 4-6 liters (4.2 to 6.3 quarts U.S.) per man.
 Pieces.  Quarts.  Ounces.  34/38 Ounces (A).  28/31 Ounces (B.)
Figure 154. Table of ration scales. All weights are in ounces.
Items in parentheses are alternatives in the same type of commodity.
(c) The calorie content of the above Japanese rations has been calculated as being as follows:
Calories Standard ration 3,470 Special ration 3,540 Reserve ration (A) 3,140 Reserve ration (B) 3,000
- Method of supply of rations. The system forward of the base area is shown in figure 150, page 174. From the field supply depots the line-of-communications transport units carry provisions to the division maintenance area, where the division transport regiment picks them up and carries them to supply points, usually in regimental headquarters areas. Here supplies are broken into unit lots and issued to units under the supervision of the Intendance personnel. The unit trains carry them to forward delivery points, which may be unit or company kitchens.
- In peacetime under normal conditions 5-days rations were carried at one time: 2-days on the man, 1-day by the unit train, and 2-days by the division transport regiment. In active theaters the amount of rations carried by forward troops is apparently ordered
for each operation, and is a combination of special field and emergency scales varying from 3 to 10-days rations. The method of transportation varies locally, but supplies are packed for ease of handling in bags or packages no heavier than 88 pounds or larger than 9 cubic feet. In the southwest Pacific Area, provisions have been floated ashore from barges or destroyers in drums and in rubber bags holding 132 pounds.
(3) Forage. The standard amount of forage per horse per day is approximately 10-12 pounds of grain, 9 pounds of hay, and 8 pounds of straw, but normally only the grain is taken into the field.
c. Ammunition. Provision and handling of ammunition is an Ordnance service responsibility. The system of supply is shown in figure 150, page 174. Bulk ammunition is stocked and issued in the base area by ammunition depots; in the forward line-of-communications through the Ordnance Depots. Distribution on the forward line-of-communications is much the same as for rations. The line-of-communications transport units carry from field ammunition depot or field ammunition branch to the division maintenance area where an ammunition column of the division transport regiment picks up regimental bulk supplies and transports them to the ammunition point. Here, unit requirements are issued under supervision of the regimental ordnance staff to unit or regimental ammunition parties, who in turn hand over to battalion ammunition parties, again under supervision.
d. Fuel, oil and lubricants. These are Ordnance issues, handled through ordnance depots, field motor-transport depots and field motor transport branch depots, to the division maintenance area. Fuel is transported in the Southwest Pacific Area by tanker or cargo vessel in either bulk or in drums up to 50-gallon capacity. Storage and filling is done in advanced base areas.
e. Ordnance. Engineer stores are supplied through their respective service depots.
f. Medical and veterinary supplies. Medical stores, which include medical supplies and patients clothing, are handled through field medical supply depots and branch depots to the line-of-communications medical units or to the division maintenance center for forward medical units. Veterinary supplies are similarly handled through field veterinary supply depots to veterinary units.
g. Army Air Force maintenance. Army Air Force supplies of all kinds, excluding rations, are handled by the Army Air service personnel and are provided from an Army Air service maintenance or branch depot in the base area. In the advanced base area are located army air service arsenals (or air maintenance stores) which include a workshop section. These issue to field air supply parks and field air depots on the forward line-of-communications, which in turn issue to the air force units.Field air repair depots are also established on the forward line-of-communications for technical maintenance, assembly, and repair of aircraft stores.
Section II. MOVEMENTS
1. SEA TRANSPORTATION. a. General. Various means of sea transportation, depending upon existing conditions and circumstances, are employed by the Japanese Army for troop movements. Cargo and passenger vessels, some converted to troop carriers, from 3,000 to 10,000 tons, are used for basic transportation; frequently, ships of less than 3,000 tons are employed. In one theater of operations "sea trucks" and various types of barges have been used for short runs. In extreme cases and under adverse combat conditions, reinforcement, maintenance, and evacuation are accomplished by means of warships such as cruisers, destroyers, and submarines.
b. Regular transport and cargo vessels. (1) Shipping Measurements. Several types of tonnage are used to denote the size of a ship or its cargo carrying capacity, namely, gross registered, net, deadweight, displacement, and measurement tonnage. An explanation of these measurements is given below:
(a) Gross registered tonnage (GRT), or simply gross tonnage is the entire inclosed space of a ship expressed in units or "tons" of 100 cubic feet.
(b) Net tonnage is the ship's volume of useful cargo space in units of 100 cubic feet.
(c) Displacement tonnage is the weight of the water displaced by the ship in tons of 2,240 pounds (long tons). Displacement loaded is the weight of the water displaced by a fully loaded ship including cargo, passengers, fuel, water, stores, dunnage, and other items necessary for use on a voyage. Displacement light is the weight of the water displaced by the ship minus the items listed above. Displacement tonnage usually is used to designate the size of naval vessels and only rarely that of cargo or passenger ships.
(d) Deadweight tonnage is the ship's total carrying capacity, expressed in long tons, and represents the difference between displacement loaded and displacement light. The effective pay load of an average cargo vessel is 80 percent of its deadweight tonnage.
(e) The shipping or measurement ton is a volume of 40 cubic feet. The size of Japanese ships usually is given in gross tons. There is no absolute relationship between the gross tonnage of a ship and its cargo carrying capacity. However, as an approximation, it may be assumed that for an average cargo ship the effective deadweight tonnage is equal to its gross tonnage multiplied by a factor of 1.5.
(2) Tonnage requirements. The amount of tonnage required to transport troops will depend upon the type of units transported; the amount of cargo; and the type of loading used; i.e., commercial, combat,
organizational, or convoy. The following figures may be used as a guide:
Classification Tonnage 1 man 3 1 horse 9 (equals 3 men). 1 field gun 18 (equals 6 men).
In moving large bodies of troops and their usual impedimenta, over long distances where proper loading facilities are available and cargo can be stowed with the least loss of space, an estimated average of 5 gross tons per man will be required. Such conditions will prevail in moving troops from home ports to theaters of operation. The following table gives the amount of estimated tonnage required to transport various units:
Unit Tonnage Army headquarters 3,400 Divisional headquarters 2,800 Infantry regiment 14,000 Field artillery regiment 24,000 Engineer battalion 3,000 Division signal unit 1,000 Transport company 5,500 Division medical unit 5,000 Field hospital 1,400
A division with a proportion of Army Troops is estimated to require 125,000 tons when making a long haul. In moving troops within the theaters of operations, particularly where opposed debarkation may be expected, or where rapid unloading is of paramount importance, light loading is employed. Thus in Rabaul-Guadalcanal movements tonnage figures averaged about 9.0 gross tons per man. The following chart is an example of this latter type of loading for various ships in a convoy:
Personnel Horses Items of freight Gross tons/man 5,823 699 167 990 8.4 4,130 477 975 8.8 5,467 457 165 2,202 12.0 5,425 491 9 595 10.9 5,859 803 309 2,127 7.3 7,006 816 166 1,698 8.6 6,498 688 113 2,230 9.5 40,208 4,431 929 10,817 9.0
(3) Convoys. Ships carrying troops usually assemble at a predetermined point, where convoys consisting of at least five ships are formed. These then proceed under a naval escort directly to their final destination, or to a staging area for transshipment to the theaters of operation. For illustration of convoy, see figure 158.
(4) Speed of convoys. The speed of convoys depends on the speed of the slowest ship in the convoy and on the extent of zigzagging. Average speed is estimated at 200 nautical miles per 24 hours; small convoys of fast ships may average a speed as high as 15 knots.
(5) Escort of convoys. Convoys are escorted most frequently by destroyers or smaller escort vessels. A convoy of 10 ships usually is accompanied by 3-4 destroyers, but larger or more important convoys may have heavier protection. Convoying distances will vary according to the safety of the passage. Changes of escorts may take place at intermediate points, particularly where a convoy passes from one patrolling area to another.
(6) Loading and discharging. Japanese are expert at handling ships and have achieved a considerable degree of efficiency in loading and discharging military cargo. The rate of loading and discharging will depend on many factors, such as availability of piers, cranes, trained stevedores, etc. It is estimated that in well equipped ports loading and unloading of a ship combat-loaded averaging 5,000 gross tons, using shore or ship's gear, could be accomplished in 3 days (operating 24 hours a day). Where piers are not available, but an adequate number of Motor Barges (MLC) can be utilized, the same rate could be achieved for combat-loaded ships. Where lighters have to be used, as many as 6 days may be required to unload a ship. Harbor congestion or lack of an adequate number of lighters and stevedoring crews may extend the required time to several weeks. General cargo can be unloaded at an average rate of 1,500 long tons per 24-hour day at piers or with MLC, and at 800 long tons per 24-hour day by lighters.
c. Transport by small craft, "sea trucks", and barges. (1) Sea trucks. These are small coastal cargo boats, luggers, and the like, generally stack aft, and varying in size from 120 to 1,000 gross tons. To these may be added latest types of wooden craft (100-300 gross tons) now being built by the Japanese on a large scale. These vessels are chiefly employed in combat zones and for coastal and inter-island transport. They can navigate in shoal waters, can be easily concealed along the coast, and generally are well adapted for the transport of small bodies of troops.
(2) Barges. In view of the danger of attack on large vessels in close waters, the Japanese Army has used landing barges extensively in the Southwest Pacific area for the transport of troops and supplies. They travel by night over set routes and hide during the day in small coves or along a stretch of coast overhung by trees. Figure 157 shows the characteristics and capacities of the barges and small transport craft used in a supply and replacement role.
d. Transport by naval vessels. (1) Cruisers may carry an average of 300 to 400 troops on long runs, and perhaps as many as 1,500 or more on short ones, but few instances of the latter type have been noted.
(2) Destroyers have been used extensively in the Southwest Pacific Area for reinforcement, evacuation,
Transport No. I No. II No. III No. IV No. V No. VI Sea truck Gross tonnage 5,493 6,493 6,869 3,793 2,746 2,883 953 29,230 total Speed (knots) 10 10 10 8.5 9 10 Unit and personnel: Army Hq 2 56 21 2 2 83 2d mixed Arty Brigade 97 100 99 50 346 AA Bn (less 2 coys) 96 90 96 80 362 Army Sigs 18 20 32 70 Ind. Eng. Regt 50 50 Ship. Eng. Regt 70 150 150 50 50 100 570 Debarkation unit 150 150 176 50 50 100 676 Div. Hq 27 67 71 7 172 Inf. Regt 500 389 828 488 2,205 Fd. Arty. Regt 81 159 134 374 Eng. Regt (less 1 coy) 50 206 225 481 Div. Sig 38 30 68 Fd. hospital 102 50 152 Unassigned troops 10 5 55 100 150 320 Water purifying unit 25 25 Total 1,203 1,324 1,923 1,052 252 200 5,954 Equipment: AA 3 3 3 3 12 Bn gun 2 1 2 2 7 Regt. gun 1 1 2 Anti-tank gun 1 2 Mt. gun 2 2 4 Light mortar 4 1 2 2 9 Machine guns 6 7 8 7 28 105 mm How 2 1 3 150 mm How 2 2 4 Rapid fire guns 3 3 Gun limbers 4 4 4 2 14 Vehicles: Wagons 26 23 23 5 77 Trucks 4 14 8 2 28 Tractors 2 4 2 1 9 Passenger cars 1 1 2 Rear cars 1 1 Landing craft: Collapsible boats 10 1 15 15 40 Large MLC 4 8 6 4 5 11 38 Outboard motors 8 6 6 20 Unsinkable drums 500 300 500 200 1,500 Logs 25 25 25 75 Planks 125 125 125 375 Various freight: Munitions (cu. m.) 2,000 2,000 1,500 200 300 1,000 7,000 Provisions and cargo (cu. m.) 500 500 1,000 Aircraft ammunition (cu. m.) 120 120 240 Belly tanks (cu. m.) 100 100 200 Aviation gasoline (drums) 540 540 1,500 2,580 Boat fuel oil (drums) 150 250 500 900 Motor gasoline (drums) 150 150 Unit baggage (pcs.) 1,911 1,678 2,559 1191 7,339 NOTES 1. Additional 958 personnel, 14 small MLC, 48 collapsible boats and 420 unsinkable drums carried on 8 destroyers.
2. Horses were not included in this transport.
Figure 158. Example of sea transportation in convoy.
and supply. Their employment as carriers usually is limited to extremely urgent cases. Such trips are short and usually made at night with loads varying according to circumstances. An average load for a 1,500-ton ship may be assumed to be 200-300 troops with some equipment or stores. On some occasions destroyers were known to have towed barges loaded with troops.
(3) Submarines are constantly employed to carry supplies and small parties of troops. Average capacity of submarines is 10 to 15 men plus stores, in addition to their crew. I-class submarines are reputed to be able to carry 50 troops and 20-40 tons of cargo, depending on whether deck cargo is carried and large submarines were reported to have carried as many as 100 troops. For transport by naval vessels, see figure 159, page 182.
LIGHT CRUISERS Class Displace-
Dimensions At maximum speed At economical speed Draft Example of loads Over-all length Beam Knots Range Knots Range Troops Cargo Ft. In. Ft. In. Miles Miles Ft. Yubari 2,890 463 40 33 1,400 10 5,500 11.8 360 Plus 42 tons, equipment and for supplies. DESTROYERS Fubuki 1,700 3796 34 34 1,100 15 4,700 10 280 Asashio 1,500 3616 33 34 960 15 5,700 9 270 3 vehicles; 2 bn guns, 2-105 mm hows; 29 boxes amm.; 20 collapsible boats, 2 MLC; 10 outboard motors. Mutsuki 1,315 336 30 34 960 15 4,350 9-10 250 Averaged 250 men, plus 60-70 tons of equipment and/or supplies. Shigure 1,368 3413 319 34 1,020 15 6,000 Hatsuharu 1,368 344 326 34 1,020 15 6,000 9-10 250 Kamikaze 1,315 336 30 34 960 15 4,350 9-10 240 Momo and Kuri 770 287 266 31 800 15 3,000 8 SUBMARINES Class Displace-
Speed on surface (Knots) Speed, submerged (Knots) Personnel carried Cargo carried (tons) Remarks New type, I class 1,150/2,200 14/20 9 Up to 40 (largest types reported to be able to carry up to 100). 350 Unconfirmed. Latest I class reportedly carry an aircraft in a deck hangar and have fittings to secure midget submarines and Daihatsu (type A MLC). RO class 650/1,000 13/17 10 Figure 159. Japanese warship classes used for transportation in Southwest Pacific Area.
2. RAIL TRANSPORTATION. a. General. (1) Japan, proper. The Japanese have considerable experience in rail transportation, both in Japan proper and on the Asiatic continent. Their railroad system is well managed, and their rolling stock is normally in good repair. Honshu, the main island, is encircled by the principal trunk lines, and the interior is well traversed with branch lines and a few trunk lines. The other prominent islands of Japan proper, Hokkaido, Shikoku, and Kyushu are also well served with railroad transportation. The rolling stock of Japan proper is estimated to consist of 6,300 locomotives, 120,000 freight cars, and 16,000 passenger cars.
(2) Korea. The railroads on the Korean peninsula run in a generally north-south direction and link the chief Korean ports with the Manchurian railroad net. There are several east-west connecting lines. The rolling stock in Korea is estimated at 600 locomotives, 7,500 freight cars, and 1,500 passenger cars, exclusive of rolling stock used on approximately 670 miles of narrow gauge railroads.
(3) Manchuria. The Manchurian railroad system, which is characterized by a series of parallel and inter-linked north-south and east-west lines, is built mainly around the South Manchurian Railways' double-tracked Dairen-Harbin line. The Manchurian rail net connects with the Korean system at five points and with the North China system at three points, while numerous strategic lines have been built to the Manchurian-Russian border.
(4) Gauge. The gauge in Japan proper is 3 feet 6 inches, while in Manchuria and Korea, except for a few narrow gauge lines in the latter, it is standard (4 feet 81/2 inches).
(5) Capacity. The average load capacity of freight cars in Japan proper is 13 tons, in Manchuria 35 tons, and in Korea 30 tons. In actual movement of freight, it generally may be assumed that the Japanese freight car capacity is half that of freight cars used in the United States. In Manchuria and Korea the capacity would be the same as for similar American freight cars. Third class passenger cars have a seating capacity of 64 passengers in Japan, while in Manchuria and Korea they accommodate from 80 to 100 passengers.
b. Troop trains. (1) Composition of trains. In Japan proper, military trains on the main trunk lines may consist of as many as 35 cars, while smaller trains which must be used on branch lines reduce the number of cars to as low as 20. In Manchuria and Korea military trains average 27-30 cars each. So far as it is practicable, complete units travel as such in separate trains; the composition of the train will vary depending on the type of material belonging to the unit. Officers usually travel in first or second class passenger cars (coaches) ; other troops travel in third class passenger cars (coaches) or freight cars used temporarily for troop movement. Livestock cars are used for horses; box cars for supplies; and flat cars for vehicles, tanks, and guns.
(2) Dispatch and speed. Troop trains can be dispatched at the rate of one every hour on the main trunk lines in Japan and Manchuria; on the branch lines the rate of dispatch will vary between 10 and 15 trains a day, depending on siding facilities. About 15 miles an hour is the average estimated speed of troop trains on the principal trunk lines in Japan, while in Manchuria it is about 20 miles
an hour. On branch lines, the average speed is reduced to 10 to 12 miles an hour.
(3) Loading. In Japan proper, a flat car will carry one 75-mm gun and two caissons; a gun tractor, limber, and gun; two large vehicles; or a large vehicle and two motorcycles. In Manchuria and Korea, the loading may differ only slightly from practices in the United States, since much of the rolling stock was purchased in the United States or followed American standard of construction. The box cars used for troop movements will accommodate between 50 and 60 men. Equipment, when loaded, is secured by blocks and ropes and usually covered by canvas. End, as well as side, ramps are used in loadings and if necessary, ramps are carried by the unit moving by rail. In Japan, entraining ordinarily can be accomplished in 1--1.5 hours, while detraining may be done in less than an hour. For movements in Manchuria or Korea, the time required would be about the same as elsewhere where standard railroad equipment is used.
(4) Illustrations. Troop movements in Japan and Manchuria are shown in individual tables below, followed by comparative figures of the estimated number of cars required for rail movements in these two regions.
Figure 160. Troop trains in Japan proper.
Train 1 2 3 Troops 510 officers and men belonging to Infantry and Artillery units. 760 officers and men belonging to Infantry. 500 officers and men belonging to Infantry. Horses 70 40 90 Material 1 gun carriage, 14 vehicles, machine guns. Infantry guns, machine guns. 4 gun carriages, 3 vehicles, machine guns. Cars 1 passenger coach, 24 closed freight cars. 1 passenger coach, 24 closed freight cars, 3 open freight cars. 1 passenger coach, 25 closed freight cars, 4 open freight cars.
Figure 161. Troop trains in Manchuria.
Trains A total of 41 trains: average length 27.5 cars. Troops 1,019 officers and warrant officers; 22,679 other troops. This force consisted of a regular infantry division with several units attached including 1 Bn. Mt. How.; 1 Tk. Bn; 4 AA units, etc. Horses 5,100 Material As required by the force. Cars 29 first and second class passenger coaches; 26 third class coaches; 315 temporary coaches (covered freight cars) ; 60 partly covered boxcars; 467 livestock cars; 115 boxcars; 115 flat cars; total, 1,127.
Figure 162. Estimated number of cars needed for Japanese troop movements by rail.
Unit Trunk lines
Army headquarters 54 26 Division headquarters 45 22 Infantry regiment 153 82 Field artillery regiment 452 242 Engineer company 15 8 Transport company 94 42 Field hospital (1) 23 11 A division with a proportion of Army troops is estimated to require 1,500-1,700 750-860
3. MOTOR TRANSPORTATION. a. General. The Japanese have several types of trucks, varying in carrying capacity from 3/4 ton to 3 tons. The most common type called the Nissan, is of 1 1/2 tons carrying capacity. In most data on motor transport movements it will be found that calculations usually are based on the employment of the
Figure 163. Standard chart showing transportation capacity of motor trucks.
Material 11/2-ton truck 1-ton truck 3/4-ton truck Soldiers, equipped 18 12 9. LMG 3 guns, 3 boxes of amm., 16 men. 2 guns, 2 boxes of amm., 11 men. 1 or 2 guns, 1 or 2 boxes of amm., 8 men. HMG, Model 92 1 gun, 3 boxes of amm., 15 men. 1 gun, 4 boxes of amm., 10 men. 1 gun, 4 boxes of amm., 7 men. Howitzer (70-mm.) Model 92 1 gun, 6 boxes of amm., 15 men. 1 gun, 3 boxes of amm., 10 men. 1 gun, 6 boxes of amm., 6 men. Mortar (50-mm.) Model 98 1 gun, 20 boxes of amm., 11 men. 1 gun, 8 boxes of amm., 9 men. 1 gun, 6 boxes of amm., 5 men. Field artillery gun (75-mm.), Model 38. 1 gun, carriage or limber, 7 men. 1 gun, carriage or limber, 1 man. Mountain (Infantry) gun, Model 41 1 gun, 10 men 1 gun, 3 men 1 gun. Rifle ammunition, Model 38 32 boxes 22 boxes 16 boxes. HMG ammunition, Model 92 60 boxes 40 boxes 30 boxes. Mortar (50-mm.) Model 98 57 boxes 38 boxes 28 boxes. Hand grenades 42 boxes 28 boxes 21 boxes. Field artillery Gun amm. (75-mm.) Model 38. 38 boxes 26 boxes 19 boxes. Provision, forage, clothing, etc. 1 1/2 tons 1 ton 3/4 ton. Gasoline 100 cans (5 U.S. gals.) 66 cans (5 U.S. gals.) 50 cans (5 U.S. gals.). Remarks: Trucks are loaded at full capacity. A fully equipped soldier's estimated weight is 150 pounds.
Figure 164. Chart of the standard rates and length of march.
Force classification Speed of march in kilometers per hour (figures in parentheses are miles per hour) 1 day's march Daytime Nighttime Km. Miles A force composed of all arms 4 (2.48) 3 to 4 (1.87 to 2.5) 24 to 40 (14.9 to 24.84). Mounted cavalry force 6 to 10 (3.73) to 6.21 4 to 5 (2.5 to 3.11) 40 to 60 (24.84 to 37.26). Fast march of horse-drawn artillery force. 10 (6.21) 8 (4.97) Motorized artillery force (field artillery). 10 to 20 (6.21 to 12.42) Dimmed lights; 6 (3.73) No lights; 4 (2.48) 100 to 120 (62 to 74.52) Motor-car company 12 to 20 7.45 to 12.42 Dimmed lights; 6 to 10 (3.73 to 6.2). No lights; 4 (2.48) Tank company: Medium tanks 12 (7.45) Dimmed lights; 6 (3.73) No lights; 4 (2.48) 80 (49.7) Light tanks 16 (9.94) Dimmed lights; 8 (4.97). No lights; 4 (2.48) 100 (62.1) Tankettes 16 (9.94) Dimmed lights; 8 (4.97). No lights; 8 (2.48) NOTES: 1. A short rest every hour was included in determining average speeds.
2.The length of march is the average distance covered per day in marching lasting a number of days.
3. The roads are considered to be average ones in level country.
11/2 ton truck. For capacity of trucks, see figure 163.
b. Requirements. Motor transport required for moving of troops is as follows:
Unit (personnel with combat equipment) Number of trucks Infantry company 16 Infantry battalion 100 Regimental gun company 25 Infantry regiment 375 FA battalion (75-mm) 80 Engineer battalion (105-mm) 120 Engineer company 16 Division signal unit 22 Division, total 3,000
(1) Estimate based on 11/2-ton capacity trucks.
(2) Unit combat and field trains included.
(3) Horses and vehicles excluded.
(4) For moving horses and vehicles, it is estimated that, generally, the additional number of trucks required would be equal to the number needed for moving troops and combat equipment.
4. MARCH TABLES AND ROAD SPACES. a. General. The Japanese Army, in its training, has for years stressed marching, and the ability to make long marches. This has resulted in the marching ability shown in Malaya, Burma, and the Pacific islands where Japanese columns have made 10-12 miles per day through heavy jungle and over terrain considered impassable. In New Guinea, a Japanese column, burdened by its heavy weapons, averaged 8--9 miles a day along jungle trails. Jungle marches are ordinarily made on a basis of 20 minutes marching and 20 minutes rest.
b. Marching ability of the various arms. See figures 164 and 165.
Section III. EVACUATION
1. GENERAL. The Division Medical Service consists of a Headquarters, three to five Field Hospitals with a capacity of 500 patients each, a Medical Unit, and Regimental and Battalion medical personnel. The Medical Unit is divided into Headquarters; Stretcher; and Ambulance Companies, whose duty is to collect the wounded, bear them to Advance Dressing Stations, give them first aid treatment, and transport them, ordinarily by horse-drawn or motor ambulance, to the Field Hospitals in the rear. The medical officer of the Regimental Headquarters supervises the medical personnel within the Regiment. Each Battalion, supervised by a Battalion medical officer, has certain medical personnel assigned to companies and platoons at the rate of one medical orderly to each platoon.
2. DETAILED ACTION. When a soldier is wounded in action he is attended by the medical orderly of his platoon who renders first aid. If necessary, the medical orderly directs the companion of the wounded soldier to help move the wounded to a place where he can be found by the stretcher bearers of the platoons of the collecting companies. The stretcher bearers carry the casualties to the First Aid Station (or Dressing Station) where supplemental first aid is rendered, and a tag attached to the patient giving details of injury and treatment. Thereafter the patient is taken to a Casualty Clearing Station (Transfer Station) and evacuated, probably by ambulance, to a Field Hospital. If seriously wounded, the patient may be transported by the Patient Evacuation Section of the Line of Communications to the Line of Communications Hospital. A variation of the above may occur if the division advances and moves up its Field Hospital. In such event, the Reserve Field Hospital of the Line of Communications moves in and takes over the serious cases of the Division Field Hospital and continues the treatment of the patient until evacuated to the Line of Communications Base Hospital.
3. EVACUATION SYSTEM. See figure 166.
Figure 165. Road space table.
Name of units Length of column
Length of column
Army headquarters 200 200 Infantry: Division headquarters 150 150 Infantry rifle company 75 Machine gun company 110 8 Battalion (less train) 440 95 20 Battalion (with train) 580 (135) 20 Regimental gun company 170 (35) 25 Regiment (total) 2,100 (500) 370 20 Cavalry: Cavalry company: In column of 2 210 15 In column of 4 120 15 Cavalry regiment: In column of 2 400-670 (320) 20 In column of 4 260-440 200 20 Horse artillery unit 1,000 Machine gun unit 550 Cavalry brigade (less trains) 3,500 800 Cavalry brigade (with trains) 1,900 800 Field artillery: Company (less train) 220 20 Company (with train) 300 Battalion (less train) 1,050 270 30 Battalion (with train) 1,230 270 30 Regiment (less train) 4,000 1,000 Regiment (with train) 4,500 1,000 Mountain artillery: Company (less unit train) 220 Company (with unit train) 330 Battalion (less unit train) 1,230 (390) 30 Battalion (with unit train) 1,400 (390) 30 Regiment (less unit train) 4,400 (1500) 30 Regiment (with unit trains) 5,400 (1500) 30 105-mm gun regiment 4,000 150-mm howitzers: Company (less train) 320 20 Company (with train) 480 20 Battalion (less train) 1,550 400 30 Battalion (with train) 2,000 400 30 Regiment (less train) 4,100 1,050 30 Regiment (with train) 4,950 1,050 30 Heavy arty brig tnpt unit 5,000 Field AA arty unit 300 Engineers: Company (less train) 120 50 8 Company (with train) 190 (60) 8 Regiment (less train) 260 120 Regiment (with train) 400 (150) Bridge building company (6,200) Transport: Company (draft) 1,600 Company (pack) (1,610) Company (MT) 1,200 Horse depot (160) 130 Signals: Signal unit (230) 200 Medical unit (240) 800 Field hospital (440) 375 NOTES: 1. Figures in parentheses indicate pack formations.
2.Foot units are calculated as marching columns of four.
3. All distances are in meters.
Figure 166. Japanese Army evacuation system.
Figure 157. Japanese small transport craft.
Types Draft (feet) Dimension (feet) Equipped men Horses Supplies (tons) Alternative loads Crew Endurance (hours) Speed (m. p. h.) Armament Uses Remarks Length Beam Field artillery gun carriage Field artillery store wagon Field artillery ammunition wagon Field ammunition car (observation) Guns (75-mm AA) Guns (105-mm) Guns (Howitzers 15-cm) Howitzers (70-mm) Guns (37-mm TK/A) Tanks Motors Provision wagon Bicycles with personnel Full Empty Tokubetsu Daihatsu Special large MLC. 69 14.8 170 20 22 6 2 light or 1 medium tank. 2 8/10 13 9.5 10.5 20 mm gun; 2 LMG fwd; 2 LMGs aft. Special large landing barge. Often used to carry tanks, heavy guns and other big eqpt. Daihatsu, Army type, "A" large MLC. 3/4 49.3 11.5 70/90 10 10/15 3 3 4 3 2 or 1; 40 men 2 3 2; 40 men 2; 28 men 1 light tank and 10 men; 2 light armored cars. 36 36 5/7 9.5 6.2 10 One or more 13, 20, or 37 mm guns and HMGs or LMG. Transport of troops and supplies. After section compartmentation capable conveying 100/120 on short runs. Will also carry 1 armored car and 15 men. Daihatsu, Navy type, "A" large MLC 3/4 45.5 10.8 80 10/15 9.8 3 3 4 3 2 or 1; 40 men 2 3 2; 40 men 2; 28 men do 7/9 9.5 6.2 10 do do Do. Shohatsu Types "B" and "C" small MLC. 2/32.7 }30/35 6.5 8.7 }30/40 3.5 15 14 3/5 10 8 7.7 mm HMG Principally for landing tps in face of the enemy, or landing light stores. Loading figures for short runs only for sea journey 1 week 10 equipped men and supplies. Barge, type "C" 49 13 50 25 2 MG fwd 1 MG aft Reconnaissance, fire support for landing operations Barge, type "D" 38.5 11 60 8 Nil Lighter work in harbors Yammasen or sampan, Barge type "E". 63.2 8.9 60 10 1 or 2 MG To penetrate shallow waters Flat bottom, airscrew propulsion. Barge, type "F" 21 7 20 2 8/10 Nil. Used as MLC at Guadalcanal Two section collapsible wooden boat. Barge, type "G" 52 13.2 50 8 Large lighters 41.2 9.9 70 10 15 3 3 4 2 2 3 30 2 Small lighters 30.8 7.9 40 6 3/4 2 2 3 2 1 1 2 15 2
Table of Contents
Previous Section (VIII) * Next Section (X)