The Emergency Escape Sequencer System (EESS) was designed and qualified for the F-22 aircraft. While the ultimate design was for the single seat F-22, a dual seat version is also supported.
The system consists of Thermal Batteries with mechanical initiators, Digital Electronic Sequencer, Cabling, and customer provided Electro-Explosive Devices (EEDs) . A separate field test set, Emergency Escape Sequencer System Tester (EESST) performs both complete system continuity tests and operational tests of the total system while installed in the aircraft. The sequencer is programmable and can be used in any single or multi-seat escape system.
The system is powered by 28V thermal batteries. Based on the initiation point, Seat Handles, Internal or External Canopy Jettison Handles, the Sequencer provides firing pulses to the EEDs to support canopy removal, ejection seat inertial reel activation(s) and ejection seat catapult firing(s). Sensing capabilities are provided to determine canopy gone.