Figure 2-30. LH ballistic manifold (SJU-17(V)2/A thru 5/A).
2. Personnel services between the seat and
2. SJU-17(V)1/A thru 5/A and 9/A only. To the
aircraft are disconnected.
cartridge actuated initiator on the LH ballistic
manifold. Gas from the initiator passes to the
3. T h e c o m m a n d s e q u e n c i n g s y s t e m
LH inlet of the catapult manifold valve to
quick-disconnect is disconnected.
initiate the catapult.
4. The emergency oxygen supply is initiated.
3. SJU-17(V)6/A only. To the LH inlet of the
5. The URT-33/A beacon is activated.
catapult manifold valve to initiate the catapult.
6. The leg restraint lines are drawn through the
Gas from the cartridge actuated initiator(s) or the
snubbers and restrain the occupant's legs to the
command sequencing system is piped to the ejection
front of the seat bucket. When the leg restraint
gun initiator via the manifold valve. Gas pressure
lines become taut, the special break rings in the
developed by the ejection gun initiator passes down the
leg lines fail and the lines are freed from the
catapult to operate the ballistic latches, retaining the
aircraft. The lines being restrained by the
IMP lanyard end fittings. As the pressure increases
snubbers prevent forward movement of the
within the catapult, the catapult piston rises, releases
legs.
the top latch, and begins to move the seat upwards.
Further movement of the piston uncovers the catapult
Near the end of the catapult stroke, the IMP
secondary cartridge, which is fired by the heat and
lanyards become taut and operate the firing
pressure of the ejection gun initiator gas. Staggered
mechanisms. Gas pressure from the IMP cartridges
firing of the catapult cartridges provides a relatively
passes:
even increase in gas pressure during catapult stroke to
1. To the start switch plungers. Closure of the
eliminate excessive g-forces during ejection.
start switches commences sequencer timing.
As the seat ascends the guide rails:
2. To the barostatic release unit release piston
1. The IMP lanyards begin to withdraw.
(from the RH IMP only).
2-27
