The U.S. Joint Heavy Lift program has dropped two of five original proposed concepts, but plans to extend its concept design and analysis phase by two years, giving new money on the same terms to companies developing the remaining designs.
A multi-service effort to develop a cargo and troop transport as big or bigger than a C-130 with vertical takeoff and landing capability, the JHL program is run by the Army Aviation Applied Technology Directorate at Fort Eustis, Va. Its goal is to foster an aircraft capable of carrying 20-30 tons internally, and external loads as well, into unimproved landing zones.
Program officials are refining model performance specifications for the next phase of concept design and settling with the armed services and the Defense Advanced Research Projects Agency on how much funding they will chip in. Program officials are seeking about $40 million in Fiscal 2008 and 2009, said Jack Tansey, JHL contracts technical representative. Some of the money might be used to build or refurbish government-owned test equipment, such as a rotor stand. In the next phase, the challenge to contractors will be to "tell us how you would modify your design in light of this new spec," Tansey said.
Following that phase, JHL officials want to hold an open competition to build two technology demonstrators, the program director, Bruce Tenney, said. That would include an engine competition and other work as well, he added.
Program officials in May said a government Joint Technology Team had decided the JHL must be able to refuel fixed-wing aircraft at 220 kt or better. That eliminated a giant flying crane proposed by Sikorsky Aircraft based on its X2 technology and a mammoth Advanced Tandem Rotor Helicopter proposed by Boeing. Those companies remain in the competition. Sikorsky has also offered an X2-based High-Speed Lifter, a C-130-sized compound helicopter. Boeing is teamed with Bell Helicopter in offering their Quad Tilt-Rotor two-wing evolution of their V-22 Osprey.
The third remaining JHL contender is Karem Aircraft’s Optimum-Speed Tilt-Rotor, a cargo aircraft-sized bird with twin rotors whose speeds would vary depending on the flight condition.
Karem’s tilt-rotor most closely resembles a concept that Tenney and other Army officials unveiled at the American Helicopter Society Forum in Virginia Beach, Va., last May called the High-Efficiency Tilt-Rotor. The HETR — "heater," as program officials pronounce it — would be a conventional, twin-rotor, single-wing tilt-rotor.
Despite the resemblance to Karem’s design, Tenney said the HETR’s purpose was merely to "crystallize the description" of the JHL and provide a vehicle for focusing on performance specifications. It wasn’t meant to imply that a twin tilt-rotor would be the only suitable candidate, he said. — By Richard Whittle