Load N°2


When prepared for manual transport the 4.2″ Chemical Mortar M-2A2 is broken down into three loads consisting of the barrel, base plate, and the standard with spade and stakes. Tools and accessories, and ammunition, comprise two additional loads. The barrel is carried by two men, each equipped with a single loop, cotton web, and cross-body shoulder strap. The barrel is suspended at the side of the men slightly below the waist level. It is supported, by shoulder straps, one strap being attached to each end of the barrel. Two men carry the base plate in the manner of a litter by means of the extended metal carrying handles. Each pair of handles is supported by a cotton web strap that passes from one of them up in front of the carrier’s shoulder, across the back of his neck, and thence in front of his other shoulder and down to the other handle. The standard, stakes, and spade are carried by two men employing one plywood litter. The standard and spade are fitted into wooden slots on the top surface of the litter, where they are bolted into place with wing nuts.

The three aiming stakes are suspended from the underside of the litter, held in a diagonal position by a single wooden slot furnished with wing nuts. The tools, sandbags, and other accessories are carried by one man using a standard plywood packboard to which there is fitted a shallow plywood box with a hinged cover. The handle of the pick mattock is carried in wooden slots fastened to one side of the box. Two 4.2-inch Chemical Mortar Shells are carried by using the standard plywood pack board which is fitted with one plywood support and two cotton web straps. The frame and straps hold the shells in position while they are transported. The shells are packed in waterproof fiber containers.

E-6 Man Pack 4.2 INCH

US Marine carrying an M-2 flamethrower light a pipe while Iwo Jima burns behind him


The Portable Flame Thrower, E-3, can be employed to project a flame to a maximum range of 80 yards. It may be used against personnel in the open or in bunkers and other field fortifications. It consists of two fuel tanks of four gallons capacity and a 205 cubic inch pressure tank combined in a portable unit; a dual connecting hose, and a gun assembly for projecting the flame. A remote control cut-off valve in the nozzle of the gun effects a quick fuel cut off which eliminates drip. The fuel is propelled by compressed air supplied by a gasoline engine-driven air compressor of the air-cooled, 4-cylinder, 3-Stage, V type. The minimum air pressure is 2300 pounds per square foot. Power consumption is approximately 5.5 Brake Horse Power, and the rate of delivery is 7 cubic feet per minute at 2000 pounds per square inch. The compressor is designed for continuous operation.

Ignition is by means of five slow-burning incendiary charges loaded into a molded plastic cylinder. These charges are ignited by the forward movement of a match head-coated push pin. The duration of burning for each charge is approximately ten seconds. For distance and long burning, a thickened fuel (Napalm) is utilized. Unthickened fuel consisting of crankcase drainings plus 10% gasoline is used for the short-range where high temperature and smoke are required. The fuel discharge is a continuous flow of approximately 8 to 10 seconds duration. Pressures in the fuel tanks are 350 pounds per square inch for thickened fuel and 250 pounds per square inch for unthickened fuel. Air pressure in the pressure tank is 1800 pounds per square foot. The effective range of the Flame Thrower E-3 with 4% Napalm is 50-60 yards, although a maximum range of 70-80 yards is obtainable. Using unthickened fuel, the difference range is 25-30 yards and the maximum range is 35 yards.

M-2 FT 1944

The M2 flamethrower saw combat use in the Pacific theater, being deployed to combat strongly fortified and entrenched Japanese positions. Following the success of the M1 flamethrower, the M2 was developed and put into combat use in 1943. Towards the end of the conflict, later models of the M2 were equipped with the fuel-thickening agent known as napalm


The development of a canister for the 4.2″ Chemical Mortar, M-2A2 is being investigated. Studies have not yet reached the point where characteristics can be determined.


Development of an incendiary shell with Pyrotechnic Mix for use in the 4.2″ chemical mortar is now underway.


The filling for incendiary projectiles developed by the Chemical Warfare Service (CWS) and designated Pyrotechnic Mixture burns intensely for a period ranging from three to fifteen minutes. The mixture is in the form of a thick jell which has a high burning temperature due to its magnesium content. The composition of the Pyrotechnic Mixture consists of a magnesium compound known as Perminetty Goop, Isobutyl-Methylaculate, Coarse Magnesium, Barium Nitrate, Ammonia Perchlorate, Gasoline, and Oil. When assembled in a projectile the Pyrotechnic Mixture surrounds a burster tube contained in an igniter tube of white phosphorous (WP). Ignition of the Pyrotechnic mix is accomplished by the white phosphorous, which is blown into the mixture upon detonation of the burster charge. Destruction of the projectile allows the ignited mixture in gobs ranging in size from a walnut to a football to be distributed over an area where it burns fiercely. The time of burning is dependent on the size of the Pyrotechnic Mixture gobs. The consensus of opinion held by CWS is that white phosphorous for incendiary purposes should preferably be replaced by Pyrotephnic Mixture in projectiles of greater weight than 100 pounds.

4.2 Inch Ammo


Burning fuel introduced into bunkers in quantity by means of flame throwers is effective in the elimination of enemy troops occupying the bunkers and will result in damaging or destroying the bunkers. Protection for flame thrower operators and the ability to bring the flame thrower within range of its objective is enhanced by mounting the Q flame thrower on an M-3 or an M-5 light tank. In addition to its use against fortified positions, it can also be employed as an antipersonnel or antitank weapon. The Q Flame Thrower, as now designed for use in a light tank, is mounted in a cylindrical basket which replaces the conical basket containing the 37-MM gun. It consists essentially of a gun assembly with an electric ignition system and air-operated fuel valve, six cylindrical fuel tanks, twenty-one compressed air drums, and a secondary fuel system. Elevation and depression are provided for by means of support in the gun base, while traverse is by rotation of the turret. The flame thrower and basket are assembled as a unit, which permits Service Forces in the field to convert a tank to flame thrower use by lifting out the 37mm gun turret basket and inserting the flame thrower basket in its place. Accessories and service kits for maintaining and filling flame throwers in the field accompany each flame thrower unit.

Image & Caption Source EUCMH & WIKIPEDIA


Fuel capacity: 125 galons
Maximum Range: 135 yards
Effective Range: 75-100 yards
Total time of fuel discharge: 50 seconds
Traverse: 3600
Depression: -10°
Elevation: +30°
Ignition System:
A – Air Atomized Gasoline
B- Electric Spark
Propellant: Compressed air or Nitrogen
Fuel: 8% Napalm


Due to the dense vegetation in the jungle, it is often impossible to detect the emissions of ordinary signal projectiles. Branches, thick foliage, and lianas interfere with the passage of signal devices and conceal them when they function. It was, therefore, considered that the use of colored smoke or flame in flame throwers would have a greater chance of being visible, inasmuch as the flame could be projected at a high angle and burn its way through intervening obstructions. The smoke incidental to the use of a flame thrower is black, and so far efforts to color it have not been successful. The investigation has, therefore, been instituted in an attempt to color the flame. So far this attempt has been without success.

Flamethrower training in England before 1944

Marines M3A1 Stuart Satan D-11 Flame Thrower Tank In Action On Saipan. Tank of the 4th Tank Battalion

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