TM 55-1520-240-T
16-1.4 EXTERNAL CARGO HOOK SYSTEM OPERATIONAL CHECK (Continued)
16-1.4
TASK
RESULT
10. Check FWD HOOK OPEN, MID HOOK
If FWD HOOK OPEN capsule (11) is lit, go to task
OPEN, AFT HOOK OPEN, and DUAL
16-1.11. If MID HOOK OPEN capsule (12) is lit,
HOOK FAULT capsules (11, 12, 13, and
go to task 16-1.12. If AFT HOOK OPEN capsule
14).
(13) is lit. go to task 16-1.13. If DUAL HOOK
FAULT capsule (14) is lit, go to task 16-1.14.
11. Check center cargo hook gage (15).
Gage shall indicate at least 2100 psi If it does
not, service center cargo hook actuator (TM 55-
WARNING
1520-240-23).
If gage indication is below 2100 psi,
inadvertent cargo hook operation could
occur resulting in loss of external load.
Injury or death can occur to personnel.
12. Press down on hook (16) on center cargo
Hook (1 6) on center cargo hook shall not move to
hook. Use wood plank.
open position. If it does, replace center cargo
hook.
WARNING
If a status light is on, it indicates that a first
failure has occurred in one of the redundant
protective circuits. A second failure while
the system is in this condition can result in
loss of external loads, resulting in personnel
injury or death.
13. Check ARMED SW FAIL status light
Light (17) shall be out. If it is on, replace HOIST/
(17).
CARGO HOOK panel.
14. Press and release ARMED SW FAIL,
Lights (17, 18 and 19) shall come on when
RELEASE SW FAIL, and GROUND
pressed and go out when released. If any light
RE LAY ACTIVATE lights (17, 18 and
does not come on. go to task 16-1.15.
19).
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Change 10 16-11
