Rockets and Missiles

Missiles can be classified in a number of different ways. Some are said to be unguided because, once they are launched, there is no further control over their flight. The German V-2 rockets were unguided missiles. Such missiles can be directed at the launch site in the general vicinity of a target, but once they are on their way, there is no further way that their path can be adjusted or corrected.

The vast majority of missiles, however, are guided missiles. This term refers to the fact that the missile's pathway can be monitored and changed either by instruments within the missile itself or by a guidance station.

Missiles can also be classified as aerodynamic or ballistic missiles. An aerodynamic missile is one equipped with wings, fins, or other structures that allow it to maneuver as it travels to its target. Aerodynamic missiles are also known as cruise missiles. Ballistic missiles are missiles that follow a free-fall path once they have reached a given altitude. In essence, a ballistic missile is fired into the air, the way a baseball player makes a throw from the outfield, and the missile (the ball) travels along a path determined by its own velocity and the Earth's gravitational attraction.

Finally, missiles can be classified according to the place from which they are launched and the location of their final target. V-2 rockets were surface-to-surface missiles since they were launched from a station on the ground in Germany and were designed to strike targets on the ground in Great Britain.

An air-to-air missile is one fired from the air (usually from an aircraft) with the objective of destroying another aircraft. One of the best known air-to-air missiles is the United States' Sidewinder missile, first put into operation in 1956. The first Sidewinders were 9.31 ft (2.84 m) long and 5.00 in (12.7 cm) in diameter, with a weight of 165 lb (5 kg) and a range of 0.68 mi (1.1 km).

A surface-to-air missile is one fired from a ground station with the goal of destroying aircraft. The first surface-to-air missile used by the United States military was the Nike Ajax, a rocket with a weight of 2,295 lb (1,042 kg), a length of 34.8 ft (10.6 m), a diameter of 12.0 in (30.5 cm),and a range of 30 mi (48 km).

Some other types of missiles of importance to the military are anti-ship and anti-submarine missiles, both of which can be launched from ground stations, from aircraft, or from other ships. Military leaders were at one time also very enthusiastic about another type of missile, the anti-ballistic missile (ABM). The ABM program was conceived of as a large number of solid rockets that could be aimed at incoming missiles. U.S. engineers developed two forms of the ABM: the Spartan, designed for long-distance defensive uses, and the Spring, designed for short-range interception. The former Soviet Union, in the meanwhile, placed its reliance on an ABM given the code name of Galosh. The ABM program came to a halt in the mid-1970s when the cost of implementing a truly effective defensive system became apparent.