Citation

Laananen DH, Winkelman KL. Int. J. Crashworthiness 1996; 1(4): 355-368.

Copyright

(Copyright © 1996, Informa - Taylor and Francis Group)

DOI

unavailable

PMID

unavailable

Abstract

The vertical component of impact forces that is often present in aircraft crashes makes an energy absorption capability essential for seats in small aircraft and helicopters. The US Army has required dynamic testing of seats for its aircraft since 1971, and the energy-absorbing seats that have been designed to meet its requirements have proven successful. Amendment of the Federal Aviation Regulations (FAR) in 1988 and 1989 to require dynamic testing of civil aircraft seats has generated increased interest among airframe and seat manufacturers in development of new energy-absorbing seat concepts. New analytical techniques are required to model these new seat concepts efficiently. The research effort described in this paper has involved a comparison of the performance of various energy-absorbing seat concepts with respect to the FAR-specified dynamic test criteria for general aviation and for rotorcraft. Three different energy-absorbing configurations were modelled using the SOMLA program, which has been developed for aircraft seat analysis. For a type of seat with guided energy-absorbing stroke, energy absorber parameters were determined that would limit the maximum lumbar force in the 50th-percentile dummy to 1500 lb (6.7 kN), as required by the FAR. Seats with energy absorption systems designed for the 50th-percentile occupant were found to limit lumbar force to tolerable levels for other sizes of occupant as well, based on assumptions of simple scaling rules. The seat models and results obtained with the models are described.

Language: en