TM 55-1520-240-T
3-1.4 PROXIMITY SWITCH OPERATIONAL CHECK (WITH )
3-1.4
INITIAL SETUP
Personnel Required:
Applicable Configurations:
Medium Helicopter Repairer
With
References:
Tools:
TM 55-1520-240-23
Aircraft Mechanic’s Tool Kit,
Equipment Condition:
NSN 5180-00-323-4692
Battery Connected
Jack 1214-151 or equal
Electrical Power On
Materials:
Aft Landing Gear Access Panels Open
None
TASK
RESULT
1.
2.
3.
Check that AFCS NO. 1 DC circuit breaker
(1) is closed.
Check that AFCS NO. 2 DC circuit breaker
(2) is closed.
Check that HYDRAULICS MAINT PNL
If AFCS NO. 1 DC circuit breaker (1) is open, close
it. If it opens again, go to task 11-3.6.
If AFCS NO. 2 DC circuit breaker (2) is open, close
it. If it opens again, go to task 11-3.11.
If HYDRAULICS MAINT PNL LTS circuit breaker (3) is
LTS circuit breaker (3) is closed.
CHECK LEFT PROXIMITY SWITCH
4. Check left GROUND CONTACT light (4).
5. Raise left aft end of helicopter with jack
(6) but do not install static lock (7). Jack
helicopter until wheel (8) is off the
ground and shock strut (9) is fully extend-
ed.
6. Lower jack (6) until clear of helicopter and re-
move it.
CHECK RIGHT PROXIMITY SWITCH
open, close it. If it opens again, go to task 8-14.10.
Left GROUND CONTACT light (4) shall be lit. If it is
not, go to task 3-1.5.
Left GROUND CONTACT light (4) shall go out. If it
does not, go to task 3-1.6.
7.
8.
9.
Check right GROUND CONTACT light (5).
Raise right aft end of helicopter with jack
(6) but do not install static lock (7). Jack
helicopter until wheel (8) is off the
ground and shock strut (9) is fully extend-
ed.
Lower jack (6) until clear of helicopter and re-
Right GROUND CONTACT light (5) shall be lit. If it is
not, go to task 3-1.7.
Right GROUND CONTACT light (5) shall go
out. If it does not, go to task 3-1.8.
move it.
FOLLOW-ON MAINTENANCE:
Disconnect battery.
Turn electrical power off.
Close aft landing gear access panels.
END OF TASK
Change 3
3-13
