This article first appeared in Aerospace Daily & Defense Report.
Work to refine concepts for a large cargo rotorcraft is moving ahead under the U.S. Army-led Joint Heavy Lift (JHL) technology effort.
JHL is the vertical take-off and landing candidate for the U.S. Air Force/Army Joint Future Theater Lift (JFTL) requirement.The first of three contracts to extend previous concept definition and analysis (CDA) work for another two years has been awarded, with the others to follow over the next week or two, says the Army's Aviation Applied Technology Directorate (AATD).
Contracts are being awarded to Bell-Boeing for the Quad Tilt Rotor, Karem Aircraft/Lockheed Martin for the Optimum Speed Tilt Rotor and Sikorsky for the coaxial-rotor X2 High Speed Lifter. The teams will update their designs to meet the new JHL model performance specification (MPS), which includes several new mission profiles that drive different aspects of the design.
The contractors ''have a requirement to provide an immediate assessment of the impact of the new MPS within 30 days of contract award," says Bruce Tenney, AATD associate director for technology. ''The government is going to do a gut check on the MPS changes and decide if a near-term update is needed for completion of the CDA."
Previous CDA studies assumed a payload of 20 tons and a C-130-size cargo box, but growth in the weight of Army Future Combat Systems vehicles has pushed the requirement closer to 30 tons and an A400M-size cargo box. The merger of JHL with the Air Force's Advanced Joint Air Combat System requirement under JFTL has also placed a greater emphasis on speed.
Work under the CDA extensions will help decide whether JHL needs two or four engines and whether folding will be required for seabasing operations. AATD also plans to demonstrate flight control laws that could reduce airframe loads and lower empty weight. These will be tested in the Army/NASA Rascal flying laboratory, a modified UH-60 Black Hawk helicopter.