Technical data

13773-001
34-10
Page 2 30 Nov 2000
2. TROUBLESHOOTING
Trouble - Pitot Static Probable Cause Remedy
Low or sluggish airspeed indica-
tion. Normal altimeter and vertical
speed indication.
Pitot tube deformed.
Leak or obstruction in pitot line.
Repair or replace damaged com-
ponent.
Incorrect or sluggish response on
all three pitot-static instruments.
Leaks or obstruction in static line. Repair or replace line. Remove
obstruction.
Pitot tube does not heat or melt
ice.
Pitot Heat switch turned OFF. Turn switch ON.
Pitot tube does not heat or melt
ice. Pitot Light ON.
Circuit breaker out. Reset circuit breaker.
Break in wiring. Test and repair wiring.
Insufficient current. Check current drain of element.
Heating element burned out. Replace element.
Trouble - Vertical Speed Ind. Probable Cause Remedy
Pointer does not set on zero. Leaking or ruptured diaphragm. Substitute known-good indicator
and check reading. Replace or
repair instrument.
Pointer fails to respond. Obstruction in static line. Check line for obstruction. Blow
out lines. (Refer to 34-10)
Pointer oscillates or fails to
respond.
Leaks in static line. Check line for obstruction. Blow
out lines. (Refer to 34-10)
Defective instrument. Replace or repair instrument.
Excessive vibration caused by
loose mounting screws.
Tighten mounting screws.
Excessive tube vibration. Tighten clamps and connections.
Trouble - Airspeed Indicator Probable Cause Remedy
Pointer fails to respond or indi-
cates improperly.
Leak in instrument case. Replace or repair instrument.
Obstruction in pitot line. Check line for obstruction. Blow
out lines. (Refer to 34-10)
Incorrect indication or pointer
oscillates.
Leak in pitot or static lines. Repair or replace damaged lines.
Tighten connections.
Leaking or ruptured diaphragm. Substitute know-good indicator
and check reading. Replace or
repair instrument.
Alternate static source valve open. Close for normal operation.