Canopy Unlatch Thruster and Cartridge

The cartridge is mounted in the canopy unlatch thruster, as shown in figure 2-5. Pressure from the canopy jettison SMDC initiator fires the thruster mounted on the canopy deck. When fired, it moves the canopy aft to disengage the latches and separate the canopy from the actuation connecting link. Thruster ballistic gas is provided to the canopy jettison rocket motor initiators.

Canopy Jettison Rocket Motor Initiators

The rocket motor initiators are mounted on the canopy deck aft of the thruster as shown in figure 2-5. The initiators receive ballistic gas input from the thruster to produce SMDC detonation to fire the rocket motors.

Canopy Jettison Rocket Motor

The rocket motors are located on either side of the canopy frame. The rocket motors are fired by the rocket motor initiators and provide the vertical thrust required to separate the canopy from the aircraft.

SMDC/FCDC Initiators

The SMDC and flexible confined detonating cord (FCDC) are located between the various ballistic components. The SMDC and FCDC provide the energy transfer stimulus used in the emergency canopy jettison system. The SMDC is sealed in stainless steel tubing to protect the cord and to contain all gases produced by explosive detonation. The FCDC is sealed in a metallic sheath, which is protected by a braid overwrap.

Figure 2-12.-Canopy jettison system schematic.

PROCEDURES

The canopy can be jettisoned by internal or external means. The following discussion summarizes both jettison procedures.

Internal Canopy Jettison

Internal canopy jettison is initiated by the internal canopy jettison lever. (See fig. 2-11.) By removing the canopy jettison safety pin and pressing down the safety button and pulling the lever aft, the canopy jettison SMDC initiator is fired. Explosive stimulus produced by the initiator is transferred through the SMDC to the emergency escape disconnect. The one-way transfer valve prevents the explosive stimulus from continuing toward the ejection seat components. The explosive stimulus continues through the emergency escape disconnect, via the FCDC, to the canopy unlatch thruster cartridge, which fires the canopy unlatch thruster. Firing the unlatch thruster pushes the canopy aft to disengage the canopy latches and separates the thruster from the connecting link. Ballistic gas produced by firing the thruster is transferred to the canopy jettison rocket motor initiators. The rocket motor initiators convert ballistic-gas pressure to explosive stimulus, which is transferred through SMDC to fire the canopy jettison rocket motors. The rocket motors produce the vertical thrust required to separate the canopy from the aircraft. (See fig. 2-12.)

External Canopy Jettison

Ground emergency external canopy jettison is started by opening the door on either the left or right side of the aircraft and removing the canopy jettison handle from its retaining clip. The handle is attached to approximately 8 feet of cable. When the cable is fully extended and pulled, the canopy jettison SMDC initiator is fired, which, in turn, initiates the emergency canopy jettison sequence. From this point on, the sequence is the same as internal canopy jettison. The cable action merely bypasses the internal canopy jettison lever. When the canopy is jettisoned, all canopy jettison ballistic devices are spent.

WARNING

Ensure that the proper canopy jettison safety pin is installed whenever the aircraft is not flying or during any maintenance task performed on the aircraft.