must use the utmost care in maintaining escape
system equipment. Proper handling and strict
compliance with the maintenance procedures
presented in the maintenance instructions manuals
(MIMs) and the maintenance requirements cards
(MRCs) are mandatory and cannot be
NOTE: The information presented in this
chapter must not be used in place of information
provided in the MIM.
The SJU-5/A ejection seat undergoes a variety
of functional checks during the 364-day special
inspection. In-depth testing of the firing
unit mechanisms, catapult gun, time-release
mechanism, drogue gun, and a complete
mechanical operational check is required. The
time-release mechanism and drogue gun checks
are discussed in the following paragraphs.
Drogue Gun Check-out
The drogue gun must be removed from the
ejection seat to accomplish the check-out. You
should make sure the drogue gun is disarmed
before performing any maintenance on it. Then,
you should remove the drogue gun barrel and
piston and inspect them for damage and
corrosion. The three tests used in the check-out
are the time-delay test, the firing pin protrusion
test, and the firing pin cocking test. These tests
must be done with the barrel and piston removed.
These tests are discussed in the following
TIME-DELAY TEST. To complete the
time-delay test, you should perform the following
steps in sequence.
1. Install the drogue gun adapter on the time-
delay test base. Connect the adapter electrical
cables to the time-delay test set timer. Then
connect the test set to a 110-volt ac 60-Hz power
supply. An air source regulated to 80 psi is
also required. Figure 6-25 reflects the correct
mounting of the drogue gun to the test set.
2. Extend the ram connecting plunger by
pressing the reset button on the test set. The reset
Figure 6-25.Drogue gun time-delay check-out.