Guy Norris/Los Angeles
Boeing Commercial Airplane Group is drawing on expertise at the former McDonnell Douglas (MDC) Phantom Works to study composite primary wing structures.
Before the recent merger, Boeing and MDC were separately involved in NASA's $130million Advanced Composites Technology (ACT) effort. MDC focused on wing research, while Boeing's involvement was tied to fuselage structures. The merger gives Boeing de facto involvement in the wing-structure research as well.
"We have started discussions with key people at Boeing-there are no definite targets yet," says ACT-wing programme director Allen Penton. While the MD-90 remains one of the most likely test applications, Penton believes that the scope could include production versions of the 737 Next Generation family, the 757 and others.
The ACT programme, which is co-ordinated by NASA's Langley Research Center, aims to achieve a 20% reduction in cost and a 25% cut in weight compared to conventional aluminium structures.
Boeing and NASA are pinning their hopes of achieving the targets on the Advanced Stitching Machine (ASM) which has been developed by Illinois-based Ingersoll Milling Machine in conjunction with Pathe Technologies. Based at Boeing's Huntington Beach site, the 28m-long machine has been designed to stitch textile composite material up to 15.25m long and almost 3m wide. It can stitch up to 20 layers of carbon fabric to a thickness of more than 30mm.
Automated ply cutters, laser projectors for positioning the plies, an autoclave and environmental controls for infusion of resin film into the stitched material are all part of the ASM installation. "We will be making a total of 14 cover panels to verify cost and weight savings," says Penton, who adds that results will be known in late 1998. "After that, we will be making a full-scale wing for a test starting in 1999 and running to 2001." This structure will be mounted on an MD-80 fuselage section for full-scale tests in the rig built for static tests on the C-17 military transport, says Penton.
Source: Flight International
