TITLE: Utility Tactical Transport Aircraft System
The Utility Tactical Transport Aircraft System (UTTAS) was a United States Army program to develop an utility transport helicopter beginning in 1972. After evaluating industry proposals, the UTTAS competition was reduced to offerings from Sikorsky and Boeing. Following a flight test evaluation of prototypes, Sikorsky's YUH-60A was selected development and production.
Background
editThe US Army considered lessons learned during the Vietnam conflict in which developed an proved its airmobile operations concept. However, the rotary wing assets utilized during the conflict evolved into combat aviation platform from commercial designs. The Bell UH-1 Huey, developed for the Army, was still fundamentally a commercial helicopter. It lacked the combat hardening needed to survive the intensity of combat operations. Consequently, it was highly modified during the war to incorporate survivability technologies to overcome this deficiency. Many UH-1's and their aircrews was lost in battle until improvements were integrated, but shortcomings remained.
In 1971, the Army initiated the UTTAS program to develop a new utility helicopter that would incorporate all the technology needed to survive in battle and protect its passengers. Army requirements were developed that defined minimum performance and survivability requirements for the future utility platform. The platform would operate in all combat intensity levels and during peacetime. The UTTAS would utilize the General Electric T700 engine being developed in parallel. Survivability features included two-engines with single engine inoperative requirement (95oF at 4000 feet), 30 minute run dry gearboxes, ballistically tolerant flight controls, r