Crashworthiness of Helicopter Composite Structures

To determine the crashworthiness characteristics of helicopter composite structures, a program was conducted for the design, fabrication, design support testing, analysis and crash testing of two full-scale composite helicopter cabin sections. The cabin section design evolved from the Bell Helicopter Textron, Inc. , (BHTI) preliminary design for the Army's Advanced Composite Airframe Program (ACAP). Crash tests were conducted for and 20-degree roll impact attitudes at a vertical impact velocity of 30 ft/sec, which is representative of the Army's vertical impact velocity requirement for noninjurious loadings if the landing gear absorbs approximately 50 percent of the crash energy. Test results from both drop tests indicate that the structural deformation was restricted to the areas designed to crush and absorb energy and that the Army's crashworthiness requirements could be met by a composite structure. Additionally, two computer crash simulation programs to aid in the design of crashworthy structures were evaluated - KRASH and DYCAST. Both proved to be very useful design tools.