High Quality Content by WIKIPEDIA articles! The Lockheed AH-56 Cheyenne was an attack helicopter developed by Lockheed for the United States Army. It rose from the Army`s Advanced Aerial Fire Support System (AAFSS) program to field the service`s first dedicated attack helicopter. Lockheed designed the Cheyenne using a four-blade rigid-rotor system and configured the aircraft as a compound helicopter. It also featured low-mounted wings, a tail-mounted thrusting propeller, and a single General Electric T64 turboshaft engine. The Cheyenne was to have a high-speed dash capability to provide armed escort for the Army`s transport helicopters, such as the Bell UH-1 Iroquois.