Transport aircraft are crucial to maintaining supply lines to forward bases that are difficult to reach by ground or waterborne access, and can be used for both strategic and tactical missions.
Air assault helicopters are usually the smallest of the transport types, and designed to move an infantry squad or section and their equipment.
This armament may be in the form of door gunners, or the modification of the helicopter with stub wings and pylons to carry missiles and rocket pods.
For example, the Sikorsky S-70, fitted with the ESSM (External Stores Support System), and the Hip E variant of the Mil Mi-8 can carry as much disposable armament as some dedicated attack helicopters.
The lower speed, range and increased fuel consumption of helicopters are offset by their not requiring a runway.