Performance of CH-46 Pilot seats in NASA Full Scale Crash Test

This paper analyzes the performance of two CH-46 crew seats that were included in the full-scale CH-46 airframe crash test conducted on 28 August 2013 at the NASA Langley Research Center. The CH-46 crashworthy armored crew seat is an adaption of the H-53 Sea Stallion crashworthy armored crew seat and was qualified by similarity. During the crash tests, the CH-46 crew seats met the required structural performance for the test; specifically, they remained attached to the floor of the aircraft (without failing the floor structure), maintained the seat's structural integrity, and restrained the occupants. This paper compares the full-scale test performance to the qualification test performance of the seat. For the co-pilot seat, the MA-16 inertia reel was augmented with a Pre-tensioning Aircrew Restraint System (PARS), which may have resulted in some differences in the test results compared to the pilot position, most notably an improvement in the measured lumbar load. The test results indicate that the crew seats' performance in the airframe crash test was satisfactory, despite significant differences in the full-scale crash test input pulse as compared to the historical qualification test pulse. It should be noted that this seat design is decades old and the airframe crash test has resulted in substantially better visibility of the seat's performance in a "real-world" situation. This, coupled with improved crashworthy seat design practices, could lead to seating systems that would not only provide good energy-absorption, but would also accommodate additional features to further improve crash injury mitigation.