Design and Qualification of a New High-Altitude Bailout Survival Ensemble

The S1034 Pilot’s Protective Assembly worn by U-2 pilots is designed to provide hypobaric protection in the event of cabin depressurization, and bailout capability in the event of ejection. The ensemble recently required a design update and re-qualification to incorporate the Combat Survivor Evader Locator (CSEL) survival radio. This paper describes the design, development and qualification of the new ensemble. The retainer assembly, which is worn exterior to the pressure suit and integrates the parachute harness and flotations, has been redesigned to include a unique pocket to accommodate the CSEL. It is critical that the CSEL is quickly accessible post-ejection, and the pocket must be easily operable by either hand. Remaining secure through all phases of nominal flight and any potential contingencies, including ejection, was also a driving requirement. A tether feature was integrated within the pocket to ensure that the CSEL would not be lost if dropped in a post-ejection scenario. Several prototype units were developed and subjected to myriad tests including cycle testing, lanyard pull tests, gloved hand accessibility, and subjective fittings within the ejection envelope of the cockpit. Once finalized, the new design required requalification for ejection. Critical testing performed included wind-blast testing and vertical drop tower testing. The wind-blast testing was conducted to ensure that the new pocket would not open during ejection, nor cause secondary effects to the suit/seat system. Vertical drop tower testing verified the ensemble’s integrity when subjected to the large shock loads associated with ejection and parachute opening. Cockpit integration tests demonstrated that the CSEL and pocket did not preclude nominal flight functions within the cockpit and further served to certify that the new ensemble was qualified for flight use. The system is now qualified, and the designs and lessons learned from this effort will be applied to future high-altitude bailout efforts.