Emergency landing dynamic conditions: a comparison with accident impact conditions

Abstract

Emergency landing dynamic conditions for small airplanes include two tests to demonstrate that seat/restraint systems of small airplanes provide protection against occupant injuries to the head, chest and spine during the principal impact of a crash sequence. The dynamic conditions for these two tests were derived from accident data for small helicopters and test data for small airplanes; accident data for small airplanes were not available before the derivation of these dynamic conditions but were available shortly after. The purpose of this study is to compare the emergency landing dynamic conditions with the helicopter accident data and airplane test data accessible before the derivation of these dynamic conditions and with the airplane accident data accessible after. The conclusion resulting from this study is that supplementary accident data for small airplanes need to be collected and the correlation of prescribed emergency landing dynamic conditions with observed accident impact conditions needs to be evaluated.