The Dynamic Environment During Emergency Descent of High Altitude/Multi-Mach Transport Aircraft.

During the post decompression emergency descent the occupants will be subjected to deceleration induced inertial loads in the direction of the flight path. According to the selected flight path the aircrafts attitude angle will fluctuate and may reach or exceed minus 10 degrees. The resultant G vector will therefore be increased and shifted forward, i.e. the resulting G-load will tend to displace the forward facing occupant forward-downwards. Experiments with chimpanzees have shown that the recovery from the decompression and subsequent hypoxic stress is faster for subjects in semi-supine position, as compared with those in seated postion. It is suggested to simulate both, the atmospheric and dynamic events in centrifuge experiments, comparing the behavioral and physiological reactions of forward as well as aft facing subjects. The results could serve for a reassessment of the value of aft-facing versus forward-facing passenger seats. Author