cartridge, and a shackle plunger assembly. The
shackle plunger is secured in the scissor shackle
plunger housing to lock the scissor mechanism in
the closed position, as shown in figure 6-21. In
this position, the drogue shackle is secured to the
ejection seat. Gas lines connect the TRM to the
manual override initiator and to the secondarys
cartridge of the drogue gun. A piston located on
top of the upper body engages the parachute
mechanical lock to secure the personnel para-
The TRM 1.5-second time-delay mechanism
delays seat/man separation and deployment of the
personnel parachute until the drogue parachutes
stabilize and decelerate the ejection seat. The
barostat assembly delays the deployment of the
personnel parachute until the pilot and the
ejection seat descend to 14,500 feet. This
delay prevents prolonged descent in the upper
atmosphere. When ejection occurs above 7,500
feet, a barostat g-controller delays the deployment
of the personnel parachute until deceleration loads
are less than 3 gs.
DROGUE GUN. The drogue gun (1) (fig.
6-20) (also shown in fig. 6-26) is mounted on the
outboard side of the left beam. The drogue gun
deploys the drogue parachutes during the ejection
sequence. The drogue gun incorporates a
0.5-second delay to ensure that the ejection seat
has cleared the cockpit prior to deploying the
drogue parachutes. The gun consists of a body
and a barrel assembly.
The drogue gun body contains a time-delay
mechanism, a spring-loaded firing pin, and two
cartridges (primary and secondary). The barrel
assembly contains a piston that is held in place
by a shear pin. The barrel holds the primary
cartridge and water seal. The primary cartridge
is mechanically fired by a trip rod attached to the
A chamber connected by a gas passage to the
barrel holds the secondary cartridge and a gas-
operated firing mechanism. This chamber ensures
that actuation of either cartridge will fire the
piston from the barrel.
INERTIA REEL ASSEMBLY. The inertia
reel (12) (fig. 6-20) is mounted on the center cross
member of the main beam assembly. During
normal operation in the UNLOCK position, the
inertia reel is free to extend or retract as required
by the pilots movements, but an automatic lock
feature will prevent rapid forward movement.
When the rapid movement ceases, the inertia reel
returns to normal operation. When the inertia reel
is in the LOCKED position, it will retract the
straps but will not allow them to extend. When
the ejection sequence is initiated, a pyrotechnic
cartridge is used to activate the inertia reel. This
retracts and locks the pilot into the correct
position for ejection.
ROCKET MOTOR INITIATOR. The
rocket motor initiator (4) (fig. 6-20) is mounted
on the outboard side of the left beam. The rocket
motor initiator consists of a cartridge chamber,
a firing mechanism, and a coiled static line. The
chamber is attached to the trombone fittings (9)
by an outlet connector. The static line is coiled
into a plastic container. The upper end of the line
is attached to the quadrant lever and the lower.
end is attached to the drogue gun trip rod.
SEAT HEIGHT ACTUATOR. The seat
height actuator is mounted in the main beam
assembly forward of the catapult gun. The
actuator permits adjustment of the seat bucket
within a vertical travel of approximately 5 inches.
The seat height actuator consists of an electric
motor and housing, gearbox, bearing housing,
and jackscrew assembly.
AIRCRAFT SEAT PARACHUTE. The
aircraft seat parachute container (13) (fig. 6-20)
is located near the top of the main beam assembly.
The parachute consists of a 22-inch controller
drogue, a 5-foot stabilizing main drogue, and a
17-foot personnel parachute. The controller
drogue deploys the -stabilizing drogue that
decelerates and stabilizes the ejection seat during
the initial phase of the ejection sequence. The
personnel parachute provides the pilot with a safe
means of descent. The parachute container
provides support for the pilots head during for-
ward acceleration or wind blast.
The personnel parachute is packed in the
container first. It is secured by flaps and a closure
pin that is attached to the personnel parachute
withdrawal line. The withdrawal line attaches the
main drogue to the apex of the personnel
parachute. Then the main and controller drogues
are packed. They are secured by four flaps and
a closure pin, which is attached to the drogue
withdrawal line. The drogue shackle secures the
parachute withdrawal line and extender strap.
Then the drogue shackle is secured in the scissor