Following ejection initiation, the lE-1 ESCAPAC system is fully automatic through rocket thrust and burnout, seat-man separation, and parachute opening. 

The 1E-1 ejection seat is a very reliable seat system that is initiated by pulling either the primary (face curtain) or secondary (lower) ejection control handle (fig. 6-1). Two cables attached to the primary ejec-tion control handle, or a single cable attached to the secondary ejection control handle, cause the firing control disconnect assembly to pivot for-ward. Two attached arms move two firing rods aft to actuate the acutating mechanism, which fires the M99 initiator( s) located between the guide rails. Through the aircraft-attached sequencing system, the power inertia reel hauls back the shoulder harness and stows the tactical air coordinator (TACCO) and sensor operator (SENSO) INCOS trays. Simultaneously, hot gas pressure from the M99 initiators( s) activates an

Figure 6-1.- Ejection seat system sequencing schematic.

aircraft-attached 0.3-second delay initiator, which fires the rocket catapult. On the for: ward two seats, an additional 0.5-second delay MK 11 MOD 0 initiator is in series with the 0.3-second delay initiator to delay forward seat ejection sequencing by 0.5 second after the rear seats eject. The eject mode selector handles on the pilot's and copilot's seat provide pilot or copilot control of individual or group ejection of crew members.

The first-phase propulsion of the rocket catapult starts the seat up in the guide rails. When the seat has moved approximately two-thirds the length of the guide rails, the second (or sustainer) phase of the rocket catapult ignites to provide boost for the additional height required during ejection. At sustainer separation, gas pressure from rocket ignition is used to ignite the seat stabilization control system, the yaw thruster, and the seat-attached 0.3-second delay ini-tiator for harness release. Before the seat clears the guide rails, the following five functions occur: crew member services to the aircraft is disconnected; the parachute arming lanyard is pulled, which arms the parachute release actuator; the lanyard con-nected to the aircraft structure actuates the emergency oxygen bottle in the survival kit to supply the crew member with emergency bailout oxygen; the yaw vane is deployed, and the quick-disconnect coupling on the right side of the seat separates. Following burnout of the yaw thruster rocket and sustainer rocket, and upon the completion of the pitch stabilization control function, the seat-attached 0.3-second delay initiator fires. Gas pressure from the initi-ator enters the harness release actuator, which drives the piston upward to rotate the bell crank mounted below the actuator to retract two survival kit retaining pins and shoulder harness pin from two inertia reel straps. Retraction of retaining pins frees the crew member and his survival equipment from the seat. The base of the clevis on the lower end of the actuator piston strikes the firing control disconnect actuating arm. Movement of the arm retracts a spring-loaded retaining pin from the firing control dis-connect assembly, and releases the ejection control handle cables from the assembly.

A crew member, who may still be holding one of the ejection control handles, is now freed from any restraints that would prevent the final separation from the seat. As the harness release actuator piston completes the stroke, the pressure within the actuator is ported to the man/ seat separator rocket, causing the rocket to ignite.

The thrust of the man/ seat separator rocket simultaneously rotates and propels the seat away from the crew member with a differential velocity of up to 25 to 30 feet per second. The probability of collison between the seat and a crew member or the parachute after separation is minimized, be-cause no attempt is made to decelerate the seat as the seat travels along a divergent trajectory. As the seat and crew member move into divergent paths, the parachute actuator is armed and the external pilot chute is deployed. After a 0.55-second de-lay, the main parachute is aerodynamically deployed. Just before the parachute shroud lines stretch, the ballistic spreading gun is fired to forcefully initiate parachute infla-tion.

If a crew member is above an altitude of 14,000 ( 500) feet, a preset aneroid in the parachute actuator delays parachute de-ployment until the crew member has de-scended to the correct altitude. The para-chute actuator delay cartridge then fires, causing parachute deployment. The crew mem-ber can select parachute deployment at any altitude by pulling the manual ripcord on the parachute.

If the automatic ejection system malfunc-tions, the crew member can pull the inter-nal jettison handle/ initiator( s) in the crew compartment to cut the window/ hatches away. Over-the-side bailout is initiated by pulling the harness release mechanism, which discon-nects the rigid survival kit and the para-chute from the seat structure. The crew member can then stand up and exit the crew compartment. When clear of the air-craft, the crew member pulls the parachute manual ripcord located on the left riser strap immediately above the parachute can-opy release fitting. The parachute flaps are thereby released, and the parachute deploys.

COMPONENTS 

Figure 6-2 shows the front and rear views of the ESCAPAC 1E-1 ejection seat assembly and its various components. Ejection Seat The ejection seat is the basic structure that supports the equipment and mechanisms necessary for crew member comfort and safety while in flight or during the ejection sequence. The seat and associated components are constructed almost entirely of aluminum. The seat is equipped with fixed window/ hatch breakers at each top forward corner to permit seat ejection through a 1/ 4-inch stretched acrylic window or hatch. At the upper center of the seat are headrest cushions that provide cushioning for the safety and comfort of the crew member. On each side of the seat are three seat rollers, which allow for vertical height adjustment during normal condi-tions and upward travel during ejection. Extended seat bucket sides protect the crew member's knees and legs from flailing during seat ejection. The seat structure supports the parachute assembly and survival kit.