TM 55-1520-240-23-7
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TEST BAROMETRIC ALTIMETER
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INITIAL SETUP
Applicable Configurations:
All
Tools:
Electrical Repairer’s Tool Kit, NSN 5180-00-323-4915
Pitot and Static Systems Tester
Power Supply, 28 VDC
Stopwatch
Materials:
None
Personnel Required:
Aircraft Electrician
Inspector
References:
TM 1-1500-204-23
TM 55-4920-231-14
Equipment Condition:
Off Helicopter Task
Test Setup
Be careful when handling altimeter.
Rough handling will damage altimeter.
1.
Supply 28 vdc to altimeter vibrator during
following test.
1.1.
Set altimeter (1) to read 0 feet altitude.
2.
Connect altimeter to test set (2) (TM
55-4920-231-14).
3.
Turn on power supply (3).
Do not exceed 3,000 feet per minute
rate of increase.
4.
Turn on and adjust test set (2) to cause altimeter
(1) to read 18,000 feet (TM 55-4920-231-14).
5.
Shut test set valve off. Check altimeter (1).
Altimeter shall not lose more than 100 feet in 1
minute (TM 1-1500-204-23).
INSPECT
Do not exceed 3,000 feet per minute
rate of decrease.
6.
Adjust test set (2) to cause altimeter (1) to 0 feet
altitude reading (TM 55-4920-231-14).
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