6/8/2009
NEWS BRIEFS
Flight Heard ‘Round The Fastener World?

Heralded as “a new era of aircraft manufacturing technology and performance,” the Air Force Research Laboratory and Lockheed Martin completed an initial test flight of the Advanced Composite Cargo Aircraft, a jet with nearly 90% fewer mechanical fasteners than traditional aircraft, the U.S. Department of Defense reports.

The 87-minute flight was made June 2 at Air Force Plant 42 in Palmdale, CA.

“The ACCA is a modified Dornier 328J aircraft with the fuselage aft of the crew station and the vertical tail removed and replaced with completely new structural designs made of advanced composite materials fabricated using out-of-autoclave curing,” according to the Defense Department.

Despite its wider and stronger fuselage tailored for military applications, the jet’s composite material cut the number of mechanical fasteners from 30,000 to about 4,000.

The flight marks the final and most significant milestone of Phase II of the Air Force Research Laboratory ACCA program, said Barth Shenk, an ACCA program manager from AFRL’s Air Vehicles Directorate at Wright-Patterson Air Force Base.

“This has the potential to change aircraft manufacturing as we presently know it, for the better,” ACCA program manager Barth Shenk was quoted as saying. “Today’s successful flight is the culmination of years of teamwork between government and industry labs involving hundreds of dedicated researchers across the country to fundamentally change the way we make airframes.”

The composite structure is manufactured “without complex tooling and the bonding process yields a 90% reduction of structural components and fasteners.”

Lacking traditional fasteners such as rivets, the composite structure is inherently aerodynamic. Likewise, composite structures could address “many of the corrosion and aging issues associated with all-metal aircraft, reducing airframe lifetime maintenance,” DoD reports.

What’s most likely to be adopted for commercial aircraft is the manufacturing processes which reduce the cost and complexity of building large airframes.

“The ACCA’s large composite sections are essentially formed, cured and bonded together in room-sized ovens, instead of using expensive autoclaves, which use a combination of heat and high pressure” which minimized part count, according to the Defense Department.

More efficient tooling, raw materials, fabrication man-hours, quality control and floor space utilization “greatly reduce cost, design and manufacturing complexity.” ©2009 GlobalFastenerNews.com