The ALCAS CFRP Door Surround Structure from scratch to the final Test Component

Abstract

Design und Fertigung vollintegrierter Türrahmenstrukturen für Passagierflugzeuge

Autoren: Markus Kleineberg, Tobias Ströhlein, Robert Kaps DLR Braunschweig, Institut für Faserverbundleichtbau und Adaptronik

The ALCAS CFRP Door Surround Structure, from scratch to the final Test Component Even though it is unquestionable that continuous fibre reinforced composite structures have an extraordinary potential to increase weight efficiency, it is still an open question if composite struc-tures are competitive when all production and assembly aspects are taken into account. Assembly of composite structures typically means bolting or riveting and this in turn means that geometric accuracy is a dominating factor besides the bare laminate properties. Integral structures like the ALCAS CFRP Door Surround Structure (DSS) are advantageous be-cause they minimise joining activities and reduce the number of critical interfaces. On the other side highly integral structures have the tendency to increase the manufacturing risk because every small local flaw can ruin the complete structural component. The way ahead within the ALCAS project was to generate a variety of possible options and than challenge these options by considering the crucial boundary conditions given within the project. The major steps in the project were the definition of the global design approach, the development of an appropriate preforming concept, the definition of suitable primary and secondary moulds and last not least the set-up of a mature resin infusion curing and demoulding strategy. To analyse the result the structure was mounted on a typical fuselage skin and was successfully tested under representative boundary conditions. The conclusion is, that today even ambitious concepts can be realised with composite structures to demonstrate the feasibility of both design and manufacturing strategies. To achieve a fully competi-tive low cost high performance CFRP structure, it is most important to link all disciplines together, beginning with systems engineering to stress and design up to production and also certification..