Japanese Flame Throwers, Intelligence Bulletin, April 1943 (Lone Sentry)

1. INTRODUCTION

While the Japanese have as yet made little use of flame throwers, they are believed to possess them in some quantity. These weapons are not carried as organic equipment by units, but are held for issue to specially trained personnel when the weapons are needed.

The information in succeeding paragraphs of this section is paraphrased from a Japanese document titled: "Use and Effectiveness of Flame Throwers." The document mentions four types of Japanese flame throwers, but gives a description of only two. One of the latter, "No. 1 Flame Thrower," has a maximum range of approximately 30 yards--according to the Japanese document--while the other, "No. 2," has a maximum range of nearly 45 yards. The No. 1 weapon will maintain a steady flame for 10 seconds as compared to 12 seconds for No. 2, and No. 1 has a fuel-tank capacity of about 4 gallons as compared to more than 10 gallons for No. 2. The two flame throwers mentioned but not described are known as Type 95 and Type SS.

The fuel capacity of the No. 2 flame thrower indicates that it is of a type too heavy for one man to carry. It is probably a two-man load.

A Japanese flame thrower, designed to be carried by one man, was captured by U.S. forces on Bataan. It has been examined by the U.S. Chemical Warfare Service, and was described in Tactical and Technical Trends, No. 18, February 11, 1943.

2. HOW THEY OPERATE

Although the Japanese document as a whole speaks of flame throwers in general, it is believed that the Japanese charts refer to a type which is carried by one man and which throws a flame approximately 30 yards.

a. Flame Chart

The Japanese chart given below is measured in meters (1 meter=39.37 inches).

b. Fuel

The fuel for flame throwers usually is a mixture of gasoline, crude oil, and kerosene. Sometimes only two of these are used. The crude oil prolongs the burning and increases the length of the flame.

During an emergency, or when no kerosene is available, a mixture composed of equal parts (by liquid measure) of gasoline and crude oil may be used. When no gasoline is available, the mixture should be composed of 2 parts of crude oil and 4 parts of kerosene.

During hot weather, the mixture should be 1 part of gasoline, 3 parts of crude oil, and 6 parts of kerosene. For cold weather, the proportion of the more volatile component should be increased: the mixture should be 1.5 parts of gasoline, 2 parts of crude oil, and 6 parts of kerosene.

For burning out emplacements, the mixture should be 1 part of gasoline, 4 parts of crude oil, and 5 parts of kerosene.

c. Safety Features

With the fuel tank full and ready for use, the flame thrower can be dropped from a height up to 6 feet without affecting the fuel tank, air pressure, or air-tight seal.

With the weapon charged and ready for use, a direct hit on the air container by small-arms fire from a distance of 110 yards will not cause it to explode or burst.

[Figure 6. Combustion chart for Japanese Flame Thrower.]

Figure 6. Combustion chart for Japanese Flame Thrower.

If the same test is applied to the lower part of the fuel tank, fuel will spread over a radius of about 7 yards. If the upper part of the tank is hit, only gas will escape; the tank will not burst or explode.

3. TACTICAL AIMS

Flame throwers are designed to kill enemy troops, to set afire or explode certain objectives, and to build up the morale of our own forces by striking fear into the enemy. They are used during an assault to break up flank defenses, or in mopping up. They also are used in the capture of centers of resistance, obstacles, and key positions, and to attack tanks at close range.

4. TRAINING

The essential objects of training are to:

a. Impart thoroughly the details of the construction and operation of the flame thrower;

b. Teach the importance of maintaining the fuel supply and of being economical with it;

c. Teach the proper maintenance of equipment;

d. Teach the importance of observing strict discipline, because of the dangers involved in training;

Use water instead of fuel in training, but act as if it were real fuel.

5. TACTICAL EMPLOYMENT

a. Against Key Positions or Emplacements

A partly consumed discharge (imperfect combustion, see fig. 6) will attain the best results against an objective. However, for momentary neutralization, such as the initial subjugation of flank defenses, a perfectly burning discharge will achieve the purpose.

In attacking special positions (such as flank defenses), temporary neutralization is achieved by inflicting casualties among the defenders and rendering their ammunition temporarily unfit for use. To insure success, follow up with an attack using explosives. Because of the black smoke and noxious gases emitted, it is impossible for the enemy to post fresh guards for 5 to 10 minutes.

In attacking enclosed positions, direct the flaming oil through the loopholes. The stream will strike an inside wall, be reflected, and reach every part of the interior.

b. Against Tanks at Close Range

Our experiments show that flame throwers at close range can temporarily neutralize tanks by inflicting casualties among the crew and by stopping the engines. Complete destruction is possible if the action of flame throwers is followed by attacks with explosives. However, best results are obtained by settingfire to combustible parts inside the tanks.