Full-Scale Static and Fatigue Testing of Composite Fuselage Section

Abstract

The influence of efficiency in new design concepts and green imperatives are on the horizon for next generation aircrafts. Bombardier Aerospace is exploring greener aircraft and has been evaluating sandwich composite structure for use in a fuselage. Two thin sheets of a high performance material, the facesheets, are adhesively bonded to each side of a thick but considerably lighter core. The benefits of using this configuration layup are the high stiffness and strength to weight ratios, high thermal insulation, energy absorption and integrated manufacturing with reduced part count. As a part of this green aircraft initiative Bombardier Aerospace has been actively engaged in fatigue and static testing of full-scale sandwich fuselage sections as a part of a composite fuselage project. The ground testing consisted of various aspects of the damage tolerance and resistance study of the fuselage section as per FAR-25 guidelines. The damage resistance was measured using drop impactor and damage tolerance testing has been carried out through pressure cycle loading. The damage resistance of the sandwich structure was evaluated using multiple impactor sizes. The various parameters like impactor size, energy imparted, visual and barely visible damage effects, as well as hidden damage levels were studied. The damage tolerance (fatigue and static testing) of the fuselage consisted of various test stages where additional parameters such as moisture ingress, freeze thaw and repairs etc. were evaluated. New NDI techniques were developed and evaluated during this multiphase project to support current ground testing and future in-service inspection methodology development. The current paper outlines impact testing on sandwich construction, NDI results of impact sites using new generation of NDI instruments and DADT results of full-scale testing. Testing is currently on-going with further studies like advanced repair technologies, moisture ingress etc. on sandwich structure and continued improvements to existing design from the test results.

Oral presentation.