A rocket launcher is a means of propelling a rocket-driven projectile from one point to another. Such launchers are different from guns, canons and grenade launchers because the rocket is self-propelled while others depend on a force within the launcher. In this respect, rocket launchers are a platform used to guide the rocket.
The term rocket launcher is usually applied to portable and hand-held or shoulder-carried devices. It can also be applied to launchers on tanks, trucks and submarines. The largest rocket launcher is the space rocket platform. This is a far more complicated device, however, and is usually not considered a rocket launcher per se.
At its most basic level, rocket launchers are a simple frame. A basic example is the bottle rocket. Air is pumped into the bottle, transferring energy into air pressure. When the air is released, it pushes out of the exhaust and expands rapidly. This propels the bottle through the air.
General rockets work on a similar propulsion basis. The exhausts produced by ignition push the rocket away from its current location. A rocket launcher facilitates this in several ways. Firstly, it provides a simple tube to house and aim the rocket. Secondly, it provides an independent ignition system. Thirdly, it avoids recoil by having vents in the back of the tube, which still allows the rocket to propel itself through the air.
The most common form of rocket launcher is the shoulder-launched rocket. This is more commonly known as the bazooka. The bazooka was originally invented by a University Professor in America called Robert H. Goddard during World War I (WWI). Goddard successfully tested the idea; however the Armistice treaty was signed a few days later. With his subsequent bout of tuberculosis, the project stalled for a number of years.
Goddard’s design is a natural evolution of mankind’s search for long distance weaponry. The aim of such weaponry is to maximize damage while minimizing risk. The inspiration for the rocket launcher is not the gun or rifle, but the mortar. This was a medieval weapon which fired a ball of stone into the air and then down onto a besieged city or castle. The mortar, in turn, owes its origin to the Roman ballista, or bolt thrower, and further back to the humble bow and finally the hunting spear tipped with flint.
The bazooka and other rocket launchers were used far more in World War II (WWII) by both the Allies and their enemies. They were designed to take out machine gun nests and to be used as anti-tank weapons. Since WWII, they have undergone developments such as the use of laser-guided rockets and the use of surface-to-air missiles against aircraft, but the basic design remains the same.