Lockheed Martin is to modify a Dornier 328Jet regional aircraft to demonstrate advanced composite airframe technology for a future tactical airlifter. The company has been selected over Aurora Flight Systems to build the US Air Force Research Laboratory's Advanced Composite Cargo (ACCA) flight demonstrator.

The 328Jet will be delivered to Lockheed's Skunk Works in Palmdale, California in November for modification, says Mike Swanson, ACCA programme manager. The fuselage aft of the flightdeck will be replaced with a new airframe built using advanced composites. This will be wider than the 328Jet fuselage and fitted with a rear loading ramp to allow the X-plane demonstrator to accommodate two 463L-standard cargo pallets.

Lockheed 328JET ACCA demonstrator
                                                                                                          © Lockheed Martin

The vertical tail will also be replaced, but the flightdeck, wing, engines, horizontal tail and systems of the 328Jet will be retained. The ACCA demonstrator is scheduled to fly in September 2008. Lockheed looked at building an all-new demonstrator, says Swanson, but cost and time constraints would have made the aircraft too small. After an extensive search, the 328Jet was selected for its size, speed and the availability of design data, he says.

The advanced composite airframe will use "out-of-autoclave" materials and processes allowing cheaper tooling and lower-temperature curing of larger components than would fit inside an autoclave. The composite fuselage will have 90% fewer parts than the original 328Jet structure. Swanson says the X-plane will be available to demonstrate other future airlifter technologies and Lockheed is working on a roadmap with AFRL.

ACCA is one of several AFRL projects developing technologies for the Advanced Joint Air Combat System, which is planned as a replacement for the US Air Force's Lockheed C-130s. These include the Speed Agile project to windtunnel-test a design capable of short take-off and landing and efficient cruise beyond Mach 0.8.

Source: Flight International