Design and Analysis of an Energy Absorbing Restraint System for Light Aircraft Crash-Impact

Abstract

The application of a miniaturized energy absorbing mechanism to a light airplane occupant restraint system is presented. The mechanism absorbs energy through the continuous plastic deformation of a steel wire, closely approximating a constant force energy absorber. The design philosophy and the installation details for the aircraft are presented. A mathematical model is used for determining the occupant response during aircraft crash. The model considers plane motion of the aircraft and the human body, the latter being approximated by five rigid body segments. Occupant displacements and curves for accelerations and restraint forces are presented for a typical survivable light aircraft crash. The experimental results and the mathematical model response suggest that incorporation of the energy absorbing mechanism would produce a significant decrease in occupant injuries and fatalities. A parametric study of the occupant/restraint system is presented. Recommendations are made on steps towards improved crash protection and survival in general aviation.