38. INFANTRY

a. Pistols

The Japanese have two types of pistols. One, known as pattern 26 (1893), is described in the Handbook on Japanese Military Forces (TM 30-480). The other, known as the 8-mm. 14 type, was first observed in the Malayan campaign.

b. Machine Guns

The Japanese are using two types of machine guns, a light and a heavy gun. Both are improvements over similar equipment adopted several years ago.

(1) Light type.—This gun was designed to replace the Nambu light machine gun, Model 1922.² First observed during the Malayan campaign, it is known as Type 96, and is patterned after the French Hotchkiss light machine gun, although it incorporates several features of the British Bren gun. It has a sling, attached to the butt stock and to the gas-cylinder bracket, for the purpose of carrying the weight from the shoulder. This feature enables the gun to be fired from a position generally used in operating a submachine gun, and it is believed that the weapon may have been referred to erroneously as a "Tommy" gun in previous reports on Japanese warfare. "Tommy" guns are not believed to be part of Japanese organizational equipment. However, it is possible that a limited number, purchased from foreign powers, may have been scattered among advance units fighting in the jungles.

The light machine gun is gas-operated, magazine-fed, and air-cooled, and may be fired automatically or semiautomatically. It has a carrying handle connected in front of the magazine, a bayonet attachment, and a bipod mount. The bipod has two positions, either folded or perpendicular to the gun barrel. The bipod has no adjustment for height. Other characteristics include the following:

Weight	_ _ _ _ _	19.18 lbs.
Weight of barrel	_ _ _ _ _	5.83 lbs.
Length, over-all	_ _ _ _ _	42 in.
Caliber	_ _ _ _ _	6.5-mm. (0.256 in.).
Rifling	_ _ _ _ _	4 grooves, right twist.
Muzzle velocity	_ _ _ _ _	2,400 ft. per sec. (approximately).
Cyclic rate of fire	_ _ _ _ _	550 rounds per min. (approximately).
Bipod mount	_ _ _ _ _	16 in. high.
Magazine capacity	_ _ _ _ _	30 rounds (approximately).

(2) Heavy type.—The heavy machine gun, 7.7-mm. (0.303 in.), was designed to replace model 3 (1914), which was 6.5-mm. caliber.³ It is of the Hotchkiss type and is air-cooled. The gun is mounted on a cross-head stand which is supported on collapsible tripod legs. The height of the stem can be adjusted. A special mounting is provided for using the gun against aircraft.

The gun and tripod usually are transported on one horse. Another horse carries four boxes of ammunition. The boxes are of two sizes, one having a capacity of 450 rounds and the other 600 rounds. The gun can fire 3,000 to 3,500 rounds continuously before becoming overheated.

Other characteristics of the gun are as follows:

Weight of gun	_ _ _ _ _	61.6 lbs.
Weight of tripod	_ _ _ _ _	60.5 lbs.
Length of gun	_ _ _ _ _	43 in.
Length of bore	_ _ _ _ _	25 in.
Rifling	_ _ _ _ _	4 grooves, right twist
Life of barrel	_ _ _ _ _	100,000 rounds (approximately)
Muzzle velocity	_ _ _ _ _	2,700 ft. per sec.
Cyclic rate of fire	_ _ _ _ _	450 rounds per min.
Maximum effective rate of fire	_ _ _ _ _	200-250 rounds per min.
Maximum range	_ _ _ _ _	4,587 yds.
Most effective range	_ _ _ _ _	850 yds.
Traversing angle	_ _ _ _ _	30° (approximately 35° graduated in mils)
Maximum angle of elevation	_ _ _ _ _	11°
Rear sight	_ _ _ _ _	Graduated from 300 to 2,700 meters

c. Mortars

At least two types of mortars, possibly three, have been used by the Japanese to date. It is known definitely that they have been using an 81-mm. mortar, similar in many respects to the United States 81-mm. mortar, and a 90-mm. chemical mortar. The British reported the capture of a 125-mm. mortar in Burma, but no details have been received.

(1) 81-mm. This mortar has the following characteristics:

(2) 90-mm. This chemical mortar has the following characteristics:

d. Grenades

Two types of hand grenades, both of cylindrical shape, have been used extensively by the Japanese. One is known as the 91 type and the other as the 97 type. The 91 type has a time fuze of 6 to 7 seconds. The fuze is ignited by tapping it sharply on some hard surface after removal of the safety pin. The 97 type is detonated by the percussion created when the grenade strikes its object.

In addition, it is reported that some use has been made of a hand grenade of the "potato-masher" type—a cylindrical cast-iron pot which is 2 inches long, 2 inches outside diameter, and 1 1/2 inches inside diameter. It is open at one end and closed at the other. Inserted in this shell is a charge consisting of 2 ounces of lyddite. A 5-inch-long wooden handle is screwed to the top of the iron cylinder. The grenade weighs about 1 pound, 3 ounces.

A gas grenade also has been developed by the Japanese, but, as far as is known, it has not been used. The gas used is hydrocyanic acid, which is classified as a casualty agent. Tests conducted with duplicates of the Japanese grenade indicate that a tank hit by one of them at vulnerable openings would be filled with a concentration of the gas 20 times the amount necessary to kill the occupants unless they were wearing adequate gas masks. The gas, which has a characteristic odor of bitter almonds, is highly volatile and is not considered very dangerous outdoors or in a large open space. The grenade, according to information found on prisoners, is designed for Use against tanks and pillboxes. It is not possible to get a high concentration of the gas inside a tank unless the grenade strikes at or near an opening. The grenade consists of about 1 pint of the acid in a round flasklike glass container. Upon impact the container breaks and the fluid acid vaporizes quickly. The M4, M8, and M9A1 canisters of service gas masks issued to United States troops give protection if the mask has been properly fitted to the wearer and is worn at the time a grenade of this type breaks. Canisters of the gas masks should be replaced as soon as possible after the attack.

e. Grenade Discharger

A grenade discharger, known as the 10-year type, model 1921, was used by the Japanese in the Malayan campaign. This type is of 50-mm. caliber and has a range of from 65 to 250 yards. It has a smooth-bore barrel 10 inches long and weighs 5 1/2 pounds unloaded. The discharger is muzzle-loaded and is fired by a striker which is operated by a lever outside of the discharger body. The weapon is fired from the ground, where it rests on a small base plate. The grenade fired from it weighs a little less than 1 pound.

f. Antitank Bombs

The Japanese are believed to have three types of antitank bombs. One consists of a soda-pop bottle filled with gasoline and fitted with a fuze and stopper. Another has a magnetized metal covering, hemisphere-shaped, and sticks to a metal surface. It explodes 5 seconds after the safety pin has been removed. The third type, very similar to the second, consists of a metal disk, to the outer edges of which small magnetized explosive charges adhere. It also explodes after 5-seconds' contact. The charges can be utilized individually in much the same fashion as hand grenades are used.

39. ARTILLERY

a. General

Before the present conflict the Japanese were known to have numerous types of artillery (see TM 30-480). At least one new type of field artillery—possibly three—has been reported since the war began. Reliable sources credited the Japanese with using an 88-mm. howitzer in the Philippines and a 77-mm. howitzer in Burma. However, no details have been received to confirm their existence or use.

b. New Field Piece

The Japanese are known to have a new split-trail field gun designed primarily for use against tanks. The gun is believed to be 75-mm. It has muzzle brakes and pneumatic tires, and the trails have driven spades to stabilize the piece for firing. The estimated range is 10,000 yards. The gun closely resembles the French Schneider field gun and may been purchased from the French.

c. 240-mm. Gun

In the Philippines the Japanese used 240-mm. railroad guns—they were known to have possessed 30 of these. The guns are adapted to transportation on either standard or narrow-gauge railroads.

A 240-mm. shell recovered in the Philippines had the following characteristics:

(1) Projectile casing—manufactured in Hiroshima, 1941; base not streamlined; narrow rotating band near the base;

(2) Projectile filling—TNT;

(3) Weight—approximately 440 lbs.;

(4) Fuze-base type, made of brass.

d. 20-mm. Antiaircraft Gun

This gun was manufactured originally by the Oerlikon Arms Co., Switzerland. Its characteristics are as follows:

Diameter of bore	_ _ _ _ _	20-mm. (.78-in.).
Weight of gun in action	_ _ _ _ _	836 lbs.
Length of barrel	_ _ _ _ _	45 in.
Muzzle velocity	_ _ _ _ _	2,720 ft. per sec.
Maximum horizontal range	_ _ _ _ _	5,450 yds.
Maximum vertical range	_ _ _ _ _	12,200 ft.
Weight of projectile	_ _ _ _ _	55 lbs.
Practical rate of fire	_ _ _ _ _	120 rounds per min.
Elevation	_ _ _ _ _	10° to 85°.
Traverse	_ _ _ _ _	360°.

e. 75-mm. Antiaircraft Gun

This gun, model 1928, is an improvement over a similar weapon, model 1922. Its characteristics are as follows:

Weight	_ _ _ _ _	5,390 lbs.
Muzzle velocity	_ _ _ _ _	2,450 ft. per sec.
Maximum horizontal range	_ _ _ _ _	15,200 yds.
Maximum vertical range	_ _ _ _ _	32,800 ft.
Practical rate of fire	_ _ _ _ _	15 rounds per min.
Weight of projectile	_ _ _ _ _	14.3 lbs.
Elevation	_ _ _ _ _	0° to 85°.
Traverse	_ _ _ _ _	360°.
Length of barrel	_ _ _ _ _	10 ft. 11 in. (approximately).
Transportation	_ _ _ _ _	Apparently tractor-drawn.

40. ARMORED VEHICLES

a. General

The Japanese have more than a dozen models of tanks,⁴ some with only slight differences, and they appear to be concentrating on five main types, namely: tankettes (or small armored reconnaissance vehicles), light tanks, cruiser tanks, heavy medium tanks, and light amphibian tanks. These are modifications of earlier models, and they have incorporated features from United States, British, French, and Russian types. Some of the tanks are said to be fitted with airplane engines, giving a high power-weight ratio.

b. Types

The following types of Japanese tanks have been encountered since the start of the current war:

(1) Tankette.—This is a light-tracked armored vehicle with one machine gun mounted in a turret. It weighs 3 to 4 tons and has two bogies and four rubber-tired wheels on each side. The crew consists of a driver and a machine-gunner. Late models of this tank are believed to be amphibian.

(2) Light tank (model 35).—This type weighs 7 tons, and carries one 37-mm. gun and two machine guns. One machine gun is located forward in the hull and the other aft in the turret. The 37-mm. gun fires armor-piercing shells. The tank has four bogie wheels, in pairs, mounted in two bogies and fitted with thick, solid-rubber tires. The bogie wheels are about the same size as the front and rear sprockets. They are not protected by skirting. The track is supported at the top by two rollers. The crew probably consists of four: a driver, a turret gunner, and two machine-gunners. The length of the tank is roughly estimated to be 15 or 16 feet and the width about 7 feet.

(3) Medium tank (cruiser tank).—This type, manned by four men, weighs 15 tons and is armed with a 47-mm. gun and two machine guns. It has armor on the sides and 1-inch armor on the front plate and turret. The turret has a 360° traverse. The tank has six bogie wheels, evenly spaced and slightly smaller than the front sprocket and rear idler. The wheels have thick solid rubber tires but no protective skirting. The tanks make no more noise than a large used truck. Their tracks are supported at the top by three rollers. The front and rear rollers have flanges or rims to prevent the tracks from slipping off, but the center roller has no outside flange and is hardly visible from a distance. The maximum speed is believed to be about 25 miles per hour. The length of the tank is believed to be about 22 feet and the width about 8 1/2 feet. A prominent feature on at least some of these is a circular handrail around the top of the turret to enable the tank to carry about 10 extra men in a field emergency.

(4) Flame-throwing tank.—In Malaya, the Japanese had a flame-thrower in an Ishi-108 tank, which is believed to weigh 38 tons. Besides the flame-thrower, the tank carried two 37-mm. guns and two machine guns. There was no report of this tank's having been used in combat.

(5) Tank trailer.—This is a small tracked vehicle with one pair of bogie wheels on each side. The suspension is of the rocker-arm type, similar to that used on Japanese tanks. The trailer, towed by various types of armored vehicles, is utilized to transport ammunition and various other types of supplies. The capacity load of the trailer is about 3,000 pounds.

(6) Armored cars.—Although several old types of armored cars are still in use, the type generally employed by the army is the Sumida six-wheel car-trolley, which is armed with one machine gun and has seven rifle or light automatic slits. By changing the wheel rims (which takes only 10 minutes), the car may be transformed into an armored trolley for running on railways. Railway guard troops use the vehicles, but to what extent is not known.

41. BOATS AND SHIPS

a. Special Transports

The Japanese have developed a special type of transport to carry troops and small landing craft. The transports have sliding or rolling doors on their sides, permitting landing craft berthed on rollers to be rolled into the water fully loaded with men and equipment. At least some of the transports also have rear slide hatches, or ramps with which to load and unload heavy equipment.

b. Landing Craft

Six types of these have been developed. Most of them are featured by double keels (for stability and strength) and by armored bows which can be dropped to permit field guns and small tanks to be run off the boats onto the beach. The armored fronts are capable of stopping 50-caliber bullets, but 30-caliber fire will penetrate the sides. The different types and some additional characteristics of the boats are as follows:

(1) Type A.—This is a large, open boat on the bow of which is a landing ramp which falls forward onto the beach, thus enabling guns to be wheeled off. The engine and coxswain usually are protected by bulletproof plating. It is used by main landing forces. The approximate overall length of the boat is 50 feet and the length at the water line is 41 feet. The length of the beam is 12 or 13 feet. The boats are propelled by low-speed two- or four-cylinder gasoline or Diesel engines and attain a speed of about 10 knots. It is estimated that the boats can carry 110 to 120 fully-equipped men.

(2) Type B.—This boat, small and of open type and holding 50 to 60 men, is used by the initial covering party. It has an over-all length of 20 to 40 feet and is powered with a two- or four-cylinder gasoline or Diesel engine. Only some of the boats have bullet-proof shields and light machine guns in the bow.

(3) Type C.—This is an armored motor launch used for close support, reconnaissance, and maintenance of communications. It is approximately 40 feet long and has a beam of 12 to 13 feet. The boat, constructed of steel plate, is believed capable of attaining a speed of 15 knots.

(4) Type D.—It is used solely as a towboat, supplementing Type A. The boat has an approximate over-all length of 30 feet and a beam of 10 feet. It is constructed of wood, similar to a standard motor launch.

(5) Type E.—This is an airplane-propeller-driven boat, about 50 feet long and 10 feet wide, which was designed for use in shallow or weed-infested water. About 10 feet of the forward underwater body rises above the water when the boat is going full speed. The draft at light load appears to be not over 2 feet.

(6) Type F.—It is constructed of steel plates and is of two sizes—30 feet over-all and 40 feet. It has a beam of 12 feet and a speed of about 9 knots.

c. Motor Torpedo Boats

The Japanese were reported several months ago to be building 70 motor torpedo boats. Some of them undoubtedly have been completed. Characteristics of the boats are as follows:

d. Tonnage Calculations

Various tonnage calculations for sea movement of Japanese forces, armament, and supplies have been estimated to be as follows:

(1) Personnel and horses.—The tonnage allowances for troops and horses vary according to the length of the voyage, route taken, and season of the year. In each case a margin is allowed for a certain quantity of stores, coal, ammunition, and vehicles.

		Long sea   voyages		Short sea   voyages   (3 days)
For each man	_ _ _ _ _	5 tons		3 tons
For each horse	_ _ _ _ _	10 tons		9 tons

(2) Matériel.—For every 1,000 tons of Japanese shipping, various vehicles (loaded), tanks, and other equipment can be shipped as shown in the below:

Trucks (3-ton)	_ _ _ _ _	12
Trucks (30-cwt.—approximately 1 1/2 tons)	_ _ _ _ _	23
Trucks (1-ton)	_ _ _ _ _	40
Tractors (field artillery)	_ _ _ _ _	50
Cars	_ _ _ _ _	40
Ambulances	_ _ _ _ _	30
Howitzers (105-mm.)	_ _ _ _ _	50
Infantry guns (37-mm.)	_ _ _ _ _	100
Tankettes	_ _ _ _ _	30
Light tanks	_ _ _ _ _	25
Medium tanks	_ _ _ _ _	15

(3) Ship dimensions in relation to tonnage.—The length, breadth, and draught of Japanese vessels in relation to tonnage is given in the following table:

Draught   feet		Length   feet		Breadth   feet		Approximate   tonnage
15		230		33		1,000
19		280		39		2,000
21		330		44		3,000
23		360		48		4,000
25		390		51		5,000
26		420		53		6,000
27		440		55		7,000
28		450		57		8,000
28		460		58		9,000
29		470		59		10,000

42. AIR FORCE⁵

a. Aircraft

Until the present time, the Japanese have used five types of bombers, five types of fighters, four types of floatplanes, and one type of flying boat, as follows:

b. Bombs

Japanese bombs are classified as army or naval. They usually consist of three parts: nose, body, and tail—either welded together, or, in addition to being welded, riveted, screwed, or double-screwed together. None of their bombs is cast or forged in one piece. Also, the three parts of the bomb are of different thickness and therefore have different degrees of fragmentation. Poor detonation is frequent. Scattered powder, large fragments, or undetonated bodies are found near bomb craters after a bombardment.

The size of bombs used by the Japanese ranges from a 2-pound antipersonnel bomb to 1,000-pound demolition bombs. Large numbers of 100-pound fragmentation types have been dropped as well as a small number of 500-pounders. A dual-purpose bomb, weighing 110.23 pounds, was used in Malaya. It is made of both high explosive and incendiary material. The incendiary part consists of 1 by 3/4 inch cylinders, which are filled with black rubber impregnated with phosphorus. The bomb explodes upon impact and its 8-inch drawn-steel casing shatters into fragments which cover a radius of 50 yards. Water will extinguish the pellets. Upon drying out, however, they will reignite up to 10 hours after the bomb has exploded. The Japanese also used white phosphorus as a filler in bombs for its incendiary effect.

The British Navy reports that the Japanese have dropped delayed-action incendiary bombs by parachute. The bombs, with a delayed action up to 12 hours, were painted black and had a small red band 6 inches from the nose. They are 6 inches in diameter and 3 1/2 feet long.

Over Corregidor the Japanese used a new type of bomb, which burst with a huge flame. Two of the bombs dropped on April 3 exploded about 500 feet above the ground.

c. Detachable Gasoline Tank

The Japanese are using an extra, detachable gasoline tank on some (probably all) of their fighter planes. The type 97 fighter, for instance, carries 70 gallons of gasoline in a fixed tank and 66 in the detachable tank. Use of the latter tank is calculated roughly to increase the range of the fighters by 560 miles.

d. Observation Balloons

These were used by the Japanese during the sieges of Singapore and Corregidor. No details of their make-up are available.

e. Barrage Balloons

The Japanese were utilizing barrage balloons in the Tokyo area when it was bombed by United States Army bombers recently.

f. Two-Way Radio

A Japanese two-way aircraft radio set removed from a crashed plane showed that it was designed and constructed to perform very efficiently, and that good materials and components were used throughout. Most of the parts appeared to be of Japanese make and apparently were copies of United States manufacture. The construction showed both United States and German influence. The set has a positive radius of communication of about 450 miles. The reception and transmission range is 300 to 500 kilo-cycles and 5,000 to 10,000 kilocycles, respectively. The set was detached when found, and it is not known from what type of plane it came. However, previous information indicated that the set was designed for use in light bombers and long-range fighters.

(1) Receiver.—The receiver is a superheterodyne and has:

(a) One radio-frequency stage, first detector; one intermediate frequency stage, second detector; power output;

(b) Plug-in coils for various bands of frequencies;

(c) Beat-frequency oscillator for continuous wave telegraphy.

(2) Transmitter.—The transmitter, which could not be removed from the mounting chassis, has the following characteristics:

(a) Plug-in coils for various bands of frequencies;

(b) Crystal-controlled (6,200 kilocycles).

(3) Generator.—No clue could be obtained as to whether the generator was run by a windmill or a battery, but the voltage regulator (in the bottom right-hand corner of the transmitter panel) was fitted in the very best technical manner. The supply of the fitting indicates that the generator may be battery-driven.

(4) Voice Transmission.—The voice can be transmitted straight or "scrambled."

43. MINES

In the Philippines the Japanese used a light, disk-type road mine.

44. CLOTHING

a. General

The dress of the Japanese soldier has not been uniform or exactly military in some respects—probably due in a large measure to clothing improvised to meet particular tactical situations. For instance, white clothing of varying types were used in the Malayan campaign so that the Japanese would not mistake the identity of each other in the jungle. Sometimes Japanese were seen dressed almost completely in white; sometimes they wore a white vest-type garment over shirts; on occasion they wore white bands on their caps or arms. In all cases clothing was very light.

b. Uniform

The regular uniform is khaki or khaki-green, with the trousers either tapered or tied at the ankles. Naval landing troops normally wear a grey-green colored uniform. On reconnaissance and infiltration missions the Japanese frequently wore only shirts, shorts, and light shoes with rubber soles. For night operations men on patrols stripped except for shorts or a loin cloth. Bicycle troops wore white undershirts over khaki or green shirts, and about half of them wore trousers and the others shorts of varying descriptions.

c. Headgear

These include skull caps, peaked caps, topees (tropical hats), and metal helmets. The topee sometimes is worn over the metal helmet. The naval landing troops wear the metal helmet with an anchor on the front. Army troops have a star on their helmets.

d. Footgear

The types vary. Besides conventional shoes, for special missions some wear light rubber-soled sneakers of the athletic type. Others wear hobnailed shoes to facilitate movement over rough terrain.

e. "Sennimbari" (1,000 Stitches)

This is a red sash worn around the waist and under the uniforms by a few Japanese soldiers. It is supposed to confer upon the soldier luck, courage, and possibly immunity from the opposition fire. One thousand stitches are used to make the sash. Members of the Japanese Patriotic Women's Association stand at street corners in Japan and ask passersby to make one stitch—thus 1,000 persons help to make a sash. A slogan on the sash reads: "Buun Chokyu" ("Everlasting Success in War").

f. Individual Items

Usually the Japanese soldier carries a minimum of equipment in addition to arms and ammunition. He wears a leather belt and a canvas haversack with an attached bag for personal belongings. Small entrenching tools are part of the normal equipment. Also, rubber belts which can be inflated for use in crossing rivers are usually carried.

g. Sniper's Equipment

Reports from the Philippines indicate that the Japanese sniper carries the following equipment:

Gas mask, green combination mosquito net, camouflage hood covering his helmet, head, and shoulders; green corded net to camouflage the rest of his body; black wire eye-screen for protection from sun glare; coil of rope to use in climbing and tying himself to trees; 5-inch-long sack of rice; small bag of hardtack; one-half pound of hard candy; package of concentrated food; can of field rations, can of coffee; can of vitamin pills; can of chlorine to purify water; mess kit; canteen; antidote for mustard gas; quinine; stomach pills; gauze pads, roll and triangular bandages; spare socks; gloves; toothbrush; flashlight with rotating varicolored lenses (one color apparently for recognition signal); and six spare lenses for eyeholes of gas mask (some usable in subzero weather).