System Operation

during emergency conditions that require emergency ground egress, seat ejection, or ditching. The canopy must be clear of the cockpit before seat ejection. Through the use of pyrotechnics, the canopy is automatically un- locked and jettisoned when seat ejection is initiated. The canopy may be jettisoned without initiating seat ejection by pulling a canopy emergency jettison initiator handle (fig. 2-4), located inside the aircraft or externally (fig. 2-5) on either side of the aircraft. System Operation Pulling the pilot or NFO face curtain or secondary firing control handle initiates seat ejection (fig. 2-3). A system initiator is fired by sear removal. This sends an explosive signal through shielded mild detonating cord (SMDC) lines to the safe-and-arm firing pins, canopy- separation charge expanding SMDC, and canopy gas generator. Expanding SMDC lines, routed through the latch hooks, break the canopy latch frangible bolts and allow the hooks to rotate upward, releasing the canopy. The canopy gas generator produces high- pressure gas that forces the canopy hydraulic actuator shaft upward, ballistically jettisoning the canopy. As the canopy leaves the aircraft, the Figure 2-5.—Canopy external jettison initiator handle. lanyard for the backup initiator becomes taut and actuates linkage to remove the backup initiator sear. This fires the initiator to send an explosive signal through a 1.1-second time delay. This signal positions an explosive charge within Figure 2-4.—Canopy emergency jettison initiator handles. 2-7