In modern warfare the missile supplements traditional artillery; both are remote delivery systems, the missile however, can operate over much larger distances.
There are many different types of missile. Perhaps one of the most commonly known is the cruise missile. The idea of the cruise missile is certainly not new. To describe it simply, this missile is an aircraft which has no pilot and has its own air-breathing jet engine. Within the missile there is a guidance system which predetermines the course to be taken and the destination. This type of missile, more often than not, travels at subsonic speeds and entirely in the atmosphere. The concept of the cruise missile can be dated back to the experimental radio-controlled flying bombs of World War I.
The first cruise missile went into service in 1976. It was one of the new US missiles, called the McDonnell Douglas Harpoon. This particular missile has a wide variety of features. It is turbojet powered, has radar homing and its range is up to 100 kilometres (62 miles). Its guidance system consists of a radar altimeter which is used when flying at sea-level. In addition it has a mid-course correction unit and also a target-detection radar. The weapons are fired from 533 millimetre (21 inch) torpedo tubes. Perhaps one of the most impressive features, is that the McDonnell Douglas Harpoon can detect two widely separated targets and head for the larger one.
