Inertially Controlled Recovery System

Ejection seat systems must operate over a wide airspeed range (0 to 600+ knots) to decelerate and recover aircrew having a wide weight range (100 to 245 lb) without exceeding the physiological acceleration tolerance of the aircrew. Currently, in order to meet these requirements main parachute deployment is delayed until airspeed decays to approximately 230 knots. An optimized recovery system would meet these requirements while also minimizing total ¿forward throw¿ for all aircrew weights. This is achieved, in theory, by deploying the main parachute at the highest feasible airspeed and modulating the rate of opening for constant deceleration at the maximum physiological tolerance level. The proposed research will determine a ¿feasible optimum¿ operating profile and generate a preliminary design for an improved recovery system that can be installed in current ejection seats as a retrofit, including adjustment of mode boundaries as necessary, but not requiring basic sequence changes or changes to other seat hardware. The technical approach includes a reefed parachute configuration capable of the required low reefing ratio (approximately 0.01) and a mechanical, deceleration sensing, continuous disreef controller.