Flare gun is basically a machine that spits out flares, with bright illumination, but without explosions. The 'flare' from the flare gun is mostly used to indicate distress calls or signals either from sea or land. In 1877, Edward Very designed the first flare gun because of which it is also called Very pistol and the US navy used it for the first time. Later after World War I, it was used throughout the world. In the case of emergency in the sea, they are used in the ships to signal, for want of help from the nearby ships. They are usually made up of plastic material and are extremely useful to ground rescuers also.
Parts of a Flare Gun
- Trigger: It is a mechanism that prompts the gun to fire. Triggering is made by pulling the lever, usually done with our index finger.
- Firing Pin: Firing pin transfers the mechanical energy from the hammer to the igniter that starts the combustion process in the gun.
- Hammer: The hammer strikes the firing pin in the flare gun.
- Shot Shell: It is a cartridge or a container that contains the materials that are required to produce the gas that is used to exert out the flare out of the barrel.
- Barrel: Barrel is a hollow metallic tube like structure through which the flare propels out with great velocity due to the expansion of gases.
Its diameter is 12 Gage (1 Gage = 18.5 mm). It works best in dry and moderate areas. The flare from the gun can reach a height of 400 feet. The speed of the flare in a projectile is around 1450 Hammer Units (HU) which is approximately 0.06858 kph. The 'flare' from the gun extinguishes when it comes in contact with an enemy flare or a solid surface. It is quite understandable that it cannot be used inside water and also the flare cannot travel inside water. The modern flare guns are small as compared to the old model flare guns.
When the trigger is pulled, the propellant is ignited and a very high pressure is created due to the combustion of the propellant and that causes the flare to propel at a high speed. The fuel takes 5 to 10 seconds to ignite and the flare leaves the gun due to deflagration or burning of the fuel. Due to the combustion, gas is produced and it expands at a very high rate, inside the flare gun. When the pressure of the gas inside the flare gun reaches to a certain level, it pushes the flare out of the barrel. The flare fuel is composed of chemicals such as strontium nitrate, sulfur, potassium perchlorate, sawdust, magnesium, dextrin, PVC, black powder, paraffin wax, etc., depending on the color of the flare required. The black powder present in the propellant helps in the process of ignition of the fuel. The temperature range due to the combustion process inside a flare gun is 1800 to 2000º F.
Types of Flares
- Red Flares: Red flares are produced due to combustion of a chemical called strontium nitrate, along with the gun powder. Red flares are used during emergency situations and to cause alerts among the public, in case of a fire emergency, etc.
- SOLAS Flares: Safety of Life at Sea is the abbreviation for SOLAS. As the name itself suggests, it is used in ships to send distress signals.
- Aerial Signals: It is a signal to get the attention of rescuers, who help to rescue during disasters.
- Parachute Flares: Using the parachutes, the flares hover around in the sky for a few seconds, thereby attracting public attention.