<div class="htmlview paragraph">The Heavy Lift Helicopter (HLH) is the airborne component of a container ship and helicopter logistics system. The U.S. Army initiated a program for development of advanced-technology components (ATC) for the HLH in June 1971 to reduce the risk associated with future procurement of an air vehicle. The components now under development by Boeing Vertol include the rotor and drive systems, flight-control system, and cargo-handling system. In addition, Boeing Vertol selected and procured representative HLH engines for use on an integrated rotor- and drive-system test rig. The HLH program has now been extended to include construction and flight-test demonstration of an austere prototype aircraft to evaluate the ATC components in a dynamic environment.</div> <div class="htmlview paragraph">This paper describes powerplant aspects of the HLH program including engine sizing, selection, and development of the Detroit Diesel Allison 501-M62B engine for the test rig, and discusses the current development program for XT701-AD-700 flight engines for use in the HLH prototype.</div>