Abstract
This chapter presents a series of full-scale structural and nondestructive inspection (NDI) tests that were conducted to investigate the performance of boron-epoxy composite doublers under realistic flight conditions. Full-scale tests were conducted on fuselage panels cut from retired aircraft. These full-scale tests studied stress reductions, crack mitigation, and load transfer capabilities of composite doublers using simulated flight conditions of cabin pressure and axial stress. Nondestructive inspections were conducted throughout the test series to validate appropriate techniques on actual aircraft structure. The test results showed that a properly designed and installed composite doubler is able to enhance fatigue life, transfer load away from damaged structure, and avoid the introduction of new stress risers (i.e., eliminate global reduction in the fatigue life of the structure). Aircraft repair practices must be continuously revisited and expanded to take advantage of new materials, new processes, and new techniques that offer both engineering and economic advantages. Through the steady and comprehensive introduction of test data, analyses, and in-service composite doubler installations on commercial aircraft a critical database is being assembled to accurately guide enhancements to formal maintenance programs. This is an important step in the evolution of composite doubler applications since it will eventually eliminate the need for each bonded composite repair to be preceded by a lengthy research and testing program.
Published Version
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call