Laboratory testing is under way on a resin-infused composite spar, developed through a European Fifth Framework research project, which is made more quickly and cheaply than spars using other composite manufacturing processes. The testing will deepen the European industry's knowledge of composite structural performance for use in major airframe components for future aircraft, such as the Airbus A400M.

The spar was produced using the resin-infused method because it was expected to be faster and cheaper than using carbonfibre pre-preg.

One of the engineering problems that had to be overcome by GKN Aerospace researchers in developing the spar was assuring the uniformity of moulding forces during production. Differences in moulding force can result in dimensional inaccuracies, but researchers solved those problems and achieved expected production cost savings.

"It's much cheaper, there is no autoclave, the capital costs for production are halved and it reduces the size of the factory space needed [because of the fewer operations]," says research participant Philip Granger, technical director of GKN Aerospace group.

The spar was designed for an A310 widebody twin-type aircraft, which is the focus of the €85 million ($114 million) Fifth Framework's Technology Application to the Near Term Business Goals and Objectives of the Aerospace Industry (TANGO) project. TANGO aims to achieve major cuts in industry operating costs and improvements in airframe structural efficiency through large-scale validation work with composite structures.

Source: Flight International