Automated Repair Method for Composite Aircraft Structures

Feb. 1, 2012
"Rapid Repair": fast and efficient repair of structures built from fiber composite materials.

Lufthansa Technik AG has for the first time developed a method for the partially automated repair of fiber composite materials on aircraft structural components. Using the new method it will be possible in future to repair the outer skins of aircraft, which these days are increasingly built from composite materials, more quickly and more efficiently. The repair method will primarily be used on aircraft fuselage and wing structures, but it can also be applied to helicopter rotor blades. A patent application has already been submitted for the method developed under the research project, which is supported by the Federal Ministry of Economic Affairs (BMWi) and which will continue through April 2012.

The actual repair process kicks in after a damage assessment has been carried out and the affected component has been cleaned. First of all the surface and contour are precisely scanned and captured to the nearest hundredth of a millimeter using an optical measurement technique (strip light projection). The bonding surfaces are then created by a computer-controlled milling machine. This process makes use of software specially developed for this project. Perfectly matching pre-cuts of individual composite layers are then produced, superimposed on the damage component, bonded and cured.

Dr. Franz-Josef Kirschfink, Director Technology Projects at Lufthansa Technik, underscores the benefits of the new method: "Thanks to close cooperation with our partners from industry and research, iSAM AG, Cassidian, GOM - Gesellschaft für optische Messtechnik, Electro Optical Systems (EOS) and Eurocopter, we have succeeded in automating virtually the entire repair process chain. The new method from Lufthansa Technik will make it possible to cut the repair time by up to 60 percent compared with the manual repair."

As most of the work is performed by robots, at the moment the method can only be applied at a fixed installation. However, this is set to change in the foreseeable future. Jan Popp, Rapid Repair project manager at Aircraft Base Maintenance, Lufthansa Technik, provides a foretaste of how the revolutionary repair method might be applied in the future: "A three-year follow-up project has already been planned to start seamlessly when the present research project finishes in April 2012. This is intended to create the basis for a mobile application so that in the long-term customers can enjoy the benefits of having their airplanes repaired on-site."

Lufthansa Technik

With 32 subsidiaries and affiliated companies and more than 26,000 staff worldwide, the Lufthansa Technik Group is one of the world's leading manufacturer-independent providers of aircraft-related technical services. Lufthansa Technik's portfolio covers the entire service spectrum of maintenance, repair, overhaul, modification and conversion, engines and components for passenger aircraft.