Flamethrowers

A flamethrower is a mechanical incendiary device designed to project a long, controllable stream of fire. They were first used by the Greeks in the 1st Century AD. In modern times, they were used during World War I, and more widely in World War II.

Some flamethrowers project a stream of ignited flammable liquid; some project a long gas flame. Most military flamethrowers use liquids, but commercial flamethrowers tend to use high-pressure propane and natural gas, which is considered safer. They are used by the military and by people needing controlled burning capacity, such as in agriculture (e.g., sugar cane plantations) or other such land management tasks. They can be designed to be either carried by the operator or mounted on a vehicle.

Modern flamethrowers were first used during the trench warfare conditions of World War I; their use greatly increased in World War II. They can be vehicle mounted, as on a tank, or man-portable.

The man-portable flamethrower consists of two elements: a backpack and the gun. The backpack element usually consists of two or three cylinders. In a two-cylinder system, one cylinder holds compressed, inert propellant gas (usually nitrogen), and the other holds flammable liquid—typically petrol with some form of fuel thickener added to it. A three-cylinder system often has two outer cylinders of flammable liquid and a central cylinder of propellant gas to maintain the balance of the soldier carrying it. The gas propels the liquid fuel out of the cylinder through a flexible pipe and then into the gun element of the flamethrower system. The gun consists of a small reservoir, a spring-loaded valve, and an ignition system; depressing a trigger opens the valve, allowing pressurized flammable liquid to flow and pass over the igniter and out of the gun nozzle. The igniter can be one of several ignition systems: A simple type is an electrically-heated wire coil; another used a small pilot flame, fueled with pressurized gas from the system.

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