Assistant chief, NASA Langley Research Center, Hampton, Va.
The paper reviews briefly the current design philosophies for achieving long, efficient, and reliable service in aircraft structures. The strengths and weaknesses of these design philosophies and their demonstrated records of success are discussed. The state of the art has not been developed to the point where designing can be done without major test inspection and maintenance programs.
A broad program of research is proposed through which a viable computerized design scheme will be provided during the next decade. The program will organize and correlate existing knowledge on fatigue and fracture behavior, identify gaps in this knowledge, and guide specific research to upgrade design capabilities. An early application of the scheme leads to an objective choice of materials to provide maximum reliability between inspections. An analytical tool has been developed that assesses the resistance of a structural configuration to fatigue and static crack propagation.
Paper ID: JTE11595J