Numerical calculation of ejection process and injury crisis evaluation

A series of math models were built to describe different movement phases and forces during the whole working process of ejection seat, from the very beginning of ejection process to the pilot's landing on earth. These models were based upon flight mechanics equations, parachute theory equations, experimental data and CFD data, and could take into consideration complicated initial ejection conditions such as rolling and diving. The working process of some ejection seat was calculated with respect to its specific parameters and aerodynamic force. The result of numerical calculation was contrasted with experimental data. The aerodynamic force's impact on pilot at different velocities was analyzed, and DRI model was employed to predict the injury crises of the ejection seat under different initial ejection condition. The result revealed that catapult and rocket could cause moderate and high injury risk to pilot, and aerodynamic force could cause high injury risk when the initial velocity of fighter was greater than 850 km/h.