Military helicopters are divided according to their primary uses. The United States Military has a universal system of classification that allows easy recognition of a helicopter's purpose by its designation. The types of helicopters most in use are: A - Attack, C - Cargo transport, H - Search and rescue, R - Reconnaissance, S - Anti-submarine warfare, M - Multi-mission or Multi-role, T - Trainer, and U - Utility.
Attack military helicopters, or AH, receive the greatest amount of recognition. The image of an AH-1 Huey Cobra coming over the trees in Vietnam is one that many Americans associate with the Vietnam War. It was originally developed to be a light, easily navigated helicopter and therefore carried light armaments. The AH-1 was later enhanced to become the Super Cobra that carries 9.5 inch (24.15 cm) Hydra rockets and Tube-launched Optically-tracked Wire-to-command-Link (TOW) anti-tank missiles.
The AH-64 Apache was designed to be a tank killer. It carries a 30 mm cannon and the choice of either 16 Hellfire laser guided rockets or 76 70mm rockets. In early 2009, the Army was testing the latest version of the AH-64, called the Apache Longbow or AH-64D. The first round of testing showed this newest version to be 400 times more accurate, and therefore more lethal, than the AH-64A.
Training military helicopters, or TH, are used for various training exercises. The Bell Th-67 is used by the US Army to train pilots, while the Navy variation is a TH-57.
The most recognizable of the cargo transport military helicopters is the double rotor CH-46 Sea Knight. The CH-57 Chinook is another twin rotor and engine helicopter that transports both cargo and troops. The CH-3 was modified to become the HH-3E, or Jolly Green Giant, that can land on water or earth in transport and rescue missions.
Some of the most successful military helicopters have been modified to several uses. For example, the Army's UH-60L Blackhawk is a modified version of the Navy's Anti-Submarine SH-60 Skyhawk. This one helicopter has also been modified to be the Air Force's multi-role MH-60G Pave Hawk as well as the Coast Guard's HH-60J Jayhawk. Each of them serves a very different purpose with the same basic machine.
Multi-role military helicopters are arguably the most useful type. Helicopters like the MH-60G are able to complete infiltration missions like supplying special forces and performing under any weather or light conditions while providing its own protection. The MH-60L is a highly upgraded Blackhawk that can be adapted to an attack helicopter when needed. These versatile machines provide much of the precision ground work that is necessary for special missions to be successful.