Several variants of the type were promptly introduced. The first combat use of the type occurred during the following year when it was deployed to the Vietnam theatre the CH-53 quickly proved its value for moving heavy payloads, particularly in the recovery of damaged aircraft. On 14 October 1964, the YCH-53A performed its maiden flight the first deliveries of production CH-53s to operational units commenced on 12 September 1966. In July 1962, Sikorsky's proposal, which was basically a scaled-up S-61R fitted with twin General Electric T64 turboshaft engines and the dynamic system of the S-64/ CH-54, was selected. The Sea Stallion was originally developed in response to a request from the United States Navy's Bureau of Naval Weapons made in March 1962 for a replacement for the Sikorsky CH-37 Mojave helicopters flown by the United States Marine Corps (USMC).
The CH-53 Sea Stallion ( Sikorsky S-65) is an American family of heavy-lift transport helicopters designed and built by the American manufacturer Sikorsky Aircraft. HH-53 'Super Jolly Green Giant'/MH-53 Pave Low
