TM 55-1520-240-T
12-4.3 WINDSHIELD WIPERS OPERATIONAL CHECK
12-4.3
INITIAL SETUP
References:
T M 5 5 - 1 5 2 0 - 2 4 0 - 23
FOLLOW-ON MAINTENANCE:
T M 5 5 - 1 5 2 0 - 2 4 0 - 2 3:
Electrical power off.
Battery disconnected.
Hose Disconnected
Applicable Configurations:
All
Tools:
Water Hose
Stop Watch
Materials:
None
Personnel Required:
67U10 Medium Helicopter Repairer
68F20 Aircraft Electrician
Equipment Condition:
T M 5 5 - 1 5 2 0 - 2 4 0 - 23
Battery Connected
Electrical Power On
Hydraulic Power Off
Visual Check Of Windshleld Wipers Performed
(Task 12-4.2)
Hose Connected To Water Supply
TASK
RESULT
1. Check that WSHLD WIPER circuit
breaker (1) IS closed.
Do not operate windshield wipers
on dry or dirty windshield. Wind-
shield can become scratched.
2. Spray pilot’s and copilot’s windshields with
water. Continue spraylng water until check is
complete.
3. Set WINDSHIELD WIPERS switch (2)
to SLOW.
If WSHLD WIPER clrcult breaker (1) is open, close
it. If it opens again, go to task 12-4.4.
Both windshield wiper blades (3) shall move back
and forth across pilot and copilot windshields ap-
proximately 80 times per minute without hitting
windshield framing. If blades don’t move or move
too slow, go to task 12-4.5. If blades hit framing,
adjust wiper arm (4) position.
4 Set WINDSHIELD WIPERS switch (2)
to MED.
5 Set WINDSHIELD WIPERS switch (2)
to FAST.
Both windshield wiper blades (3) shall move
faster. If not, go to task 12-4.5.
Both wiper blades (3) shall move back and forth
across windshields approximately 138 times per
minute. If not, go to task 12-4.5. If excessive noise
comes from direction of overhead panel, go to task
12-4.6
Both wiper blades (3) shall immediately stop. If
not, replace WINDSHIELD WIPERS switch (2).
6. Set WINDSHIELD WIPERS switch (2)
to OFF.
7. Set and hold WINDSHIELD WIPERS
switch (2) to PARK.
8 Release WINDSHIELD WIPERS switch
(2).
12-74
Each wiper blade (3) shall move to inboard edge of
it’s windshield (park position). If not go to task 12-
4.7.
WINDSHIELD WIPERS switch (2) shall return to
OFF position. If not, replace WINDSHIELD
WIPERS switch.
END OF TASK
