is able to initiate command-sequenced ejec-
of surface contact, the occupant has oxygen from a
tion?
system in the survival kit. At an altitude between
14,500 and 11,500 feet, the barostat assembly releases
Q1-8. During ejections below 13,000 1,500 feet,
the time-release mechanism escapement, initiating its
what assembly will actuate at approximately
timed operation. Upon actuation of the time-release
0.5 second after ejection?
mechanism, occupant release and separation occurs the
Q1-9. What procedure must be initiated if the
same way as ejection sequence below 13,000 1,500
time-release mechanism fails?
feet.
EJECTION SEQUENCE FOR MANUAL
COMPONENTS
SEPARATION
LEARNING OBJECTIVE: Identify the ma-
If the time-release mechanism fails, or if the terrain
jor ejection seat components.
altitude is above the setting of the barostat, the occupant
The components discussed below include the
must initiate manual separation from the seat and
rocket motor (DODIC M938, M939, and M940), rocket
deployment of the personnel parachute. The following
motor initiator, color-coded brackets, main beam as-
will occur:
sembly, top latch mechanism, time-release mechanism,
1. The occupant puts the emergency restraint
personnel parachute, upper restraint harness, and
release in its full up unlock position, releasing
parachute harness sensing-release units.
the upper harness locks, personnel parachute
restraint locks, survival kit to seat lock, and
ROCKET MOTOR (DODIC M938,
leg-restraint line locks. This action reduces
M939, AND M940)
sticker clip tension and fires the guillotine
cartridge.
Each Martin-Baker MK GRUA-7 ejection seat has
2. The gas from the cartridge operates the
a rocket motor attached to the underside of the seat
guillotine unit to sever the personnel parachute
bucket (fig. 1-3). The rocket motor is connected by a
withdrawal line.
3. The occupant must now rotate forward and
push the seat bucket with his hands to separate
from the seat.
4. When free of the seat, the occupant must pull
the personnel parachute manual release (para-
chute ripcord handle) to deploy the personnel
parachute.
AFT
SEPARATION OF PARACHUTE FROM
FLEXIBLE GAS HOSE
CREWMEMBERS
CAM FOLLOWER
ENGAGED IN
INCLINED TRACK
Manually opening the canopy release assembly is
the primary means of separating the parachute from the
ATTACHMENT BOLT
crewmember. The SEAWARS (a backup mode) auto-
VIEW LOOKING UP
matically releases the parachute from the crewmember
within two seconds after seawater entry. When the
CAM FOLLOWER
parachute harness sensing release units are immersed in
NOZZLES
CENTER BODY
seawater, cartridges fire to separate the parachute risers
from the canopy release assembly. Immersion in fresh
GAS OPERATED
IGNITER UNIT
water will not activate the parachute harness sensing
AFT
release units.
DUST CAP
TYPICAL
Q1-6. During command sequenced ejection, the
6 PLACES
NOZZLES
sequence gas generator sear is extracted by
rotation of what assembly?
ROCKET MOTOR
(BOTTOM VIEW)
Q1-7. With the CMD EJECT SELECT handle in the
AMEf0103
ECMO command position, what crewmember
Figure 1-3.--Rocket motor (DODIC M938, M939, and M940).
1-7
