Preliminary Investigation of the Seated Height Limit for Safe Through-the-Canopy Ejection from the CT 114 Aircraft.

摘要

In a number of ejections from the CT 114 aircraft, the canopies have failed to jettison. The potential for head or neck injuries exists if the helmet were to contact the canopy ahead of the canopy breaker. A study was conducted to determine the seated height limit for safe through-the-canopy ejections, and the number of pilots whose seated height exceeds the safe seated height. The study involved correlating the seated heights of a number of subjects with static measurements, taken in a CT 114 ejection seat, of the vertical distance between the top of their helmets and the canopy breaker. The safe seated height was found to be 88.0 cm. for dual visor helmets, and 90.6 cm. for the helmet shell alone. These limits would cut off about 75% and 45% of the pilots respectively. It is recommended that further studies be conducted to determine what effect the actual shape of the canopy may have on the safe seated height, and what effect the ejection forces have on pilot's seated height during the first moments of ejection. (Author)