Crash-Resistant Crewseat Limit-Load Optimization through Dynamic Testing with Cadavers

摘要

The threshold of spinal injury for seated humans subjected to +Gz loading was investigated. The +Gz loading was induced by simulating crash conditions typically found in helicopter crashes, and modified by the use of energy-absorbing mechanisms incorporated in the seat structure. Fifteen tests were conducted with unembalmed cadavers as human surrogates at various limit-load settings to attempt to identify the load threshold causing spinal injury. Bone strength analysis was used to normalize the results of the cadaver test program. Performance data and autopsy results for the 15 crash tests are presented. A correlation was derived relating the frequency of spinal injury to the energy absorber limit-load factor for use in design of crashworthy seating systems. Comparison of the incidence of spinal injury between the experimental test data developed through testing with cadavers and field performance of production energy-absorbing seats is discussed. The report also contains a discussion of the biomechanics of trauma associated with the human spine, including mechanical properties of the spine, typical injury mechanisms for +Gz loading, and theoretical models for predicting injury.