Evaluation of the Safety Performance of Ejection Seat Cushions

Several operational and prototype ejection seat cushions were selected for the evaluation of their performance for the prevention and reduction of spinal injuries. The evaluation was performed using impact tests on the vertical deceleration tower, where a cushion was placed between the seat pan and the occupant (a 50 percentile Hybrid III manikin) and was subjected to +Gz impact at 8, 10, and 12 g, respectively. For comparison, tests were also conducted on a bare seat pan without a cushion. Based on the test data, analyses were performed to determine the dependency of certain occupant responses and structural responses on the cushions. The cushions were ranked in the sequences illustrating their performance merit in terms of the peak values of the lumbar force and other responses.