TM 55-1520-240-23-7
8-38
TEST BAROMETRIC ALTIMETER
(Continued)
8-38
7.
Rotate adjustment knob (3) to bring barometric
scale (4) from 28.10 to 31.00. Check that
no binding occurs and that pointers (5) move
smoothly.
8.
Rotate adjustment knob (3) to bring barometric
scale to 29.92. Record altitude reading.
9.
Rotate adjustment knob (3) to bring barometric
scale to 28.50. Record altitude reading.
10.
Compare readings from steps 8 and 9. The
difference shall be between 1,315 and 1,365
feet.
INSPECT
11.
Rotate adjustment knob (3) to bring barometric
scale to 29.92. Record reading.
12.
Rotate adjustment knob (3) to bring barometric
scale to 30.90. Record reading.
13.
Compare readings from steps 11 and 12. The
difference shall be between 868 and 918 feet.
INSPECT
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