(3)
Gages
(a)
Pitot system test gage - required to indicate 10 to 34 inches of mercury (absolute) with an accuracy of |0.16 (readable to |0.03) inch of mercury or |5 (readable to |1) knots.
(b)
Differential pressure gage - required to indicate 10 inches of mercury differential pressure (minimum) with an accuracy of |0.010 inch of mercury.
(4)
Flow restrictors, control valves, cutoff valves, pressure tape and port seals as required.
B. Consumable Materials
(1) G00000, Soft rag for wiping off pitot-static probe
C. References
(1) 34-11-01/601, Pitot-Static Probe
D. Access
(1) Location Zone
211 Passenger Cabin Nose to First Door, LH
E. Procedure
S 865-264
CAUTION: MAKE SURE THAT YOU DO NOT APPLY ELECTRICAL POWER TO THE PROBE
_______ HEATERS. YOU CAN CAUSE DAMAGE TO THE PITOT-STATIC PROBES.
(1) Open these circuit breakers and attach DO-NOT-CLOSE tags:
(a) P6 Main Power Distribution Panel
1) 6D30 PROBE HEAT PITOT L
2) 6E01 PRIM T/E FLAP CONT AC
3) 6E02 PRIM T/E FLAP CONT DC
S 485-021
WARNING:_______MAKE SURE THAT THE PROBE HEAT IS NOT ON. YOU CAN CAUSE INJURY TO PERSONS.
(2) Install the pitot-static probe adapter on the upper left pitot-static probe.
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CAUTION:_______DO NOT EXTEND THE SEALS INTO THE PITOT DRAINS. YOU CAN CAUSE DAMAGE TO THE SURFACE IN THE AREA WHEN YOU REMOVE THE SEALS.
(a) Seal the pitot chamber drain hole on the bottom of the probe with vinyl adhesive tape.
NOTE: You will find the drain hole, approximately 2.25 inches, aft of the probe tip.
CAUTION: MAKE SURE THAT YOU FLUSH THE PROBE ADAPTER WITH WATER
_______
BEFORE YOU ATTACH THE ADAPTER TO THE PROBE. YOU CAN CAUSE
DAMAGE TO THE PROBE OR THE ADAPTER.
(b) Flush the pitot-static probe adapter with water.
NOTE:____ Use equal parts of water and ethylene glycol when the
temperature is between 32 degrees F and -40 degrees F.
(c) Install the probe adapter on the probe.
S 485-022
CAUTION: MAKE SURE THAT THE PITOT-STATIC PROBE HAS NO ADDED WEIGHT FROM
_______ THE TEST HOSES. YOU CAN BEND OR TWIST THE PITOT-STATIC PROBE OUT OF TOLERANCE.
(3) Connect the pneumatic test set to the pitot-static probe adapter.
(a)
Connect the pitot (pressure) source in the pneumatic test set through the pitot control valve to the pitot cutoff valve.
(b)
Connect the pitot inlet of the probe adapter to the pitot cutoff valve through the test gage and flow restrictor.
(c)
Open the pitot cutoff valve.
S 795-023
(4) The Captain's Pitot System Leak Test.
CAUTION: MAKE SURE THAT THE PITOT LINE PRESSURE IS EQUIVALENT OR
_______ MORE THAN THE STATIC LINE PRESSURE. KEEP THE PITOT PRESSURE CHANGE BELOW 300 KNOTS FOR EACH MINUTE. MAKE SURE THAT THE DIFFERENTIAL PRESSURE STAYS BETWEEN 0 AND
10.19 INCHES OF MERCURY. YOU CAN CAUSE DAMAGE TO THE PITOT-STATIC SYSTEM.
(a) Apply pressure to the captain's pitot system equal to 300 |5 knots of airspeed (ambient pressure plus 4.53 |0.16 in. Hg).
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CAUTION:_______ HOLD THE PRESSURE, AS AN ALTERNATIVE, BEHIND THE CUTOFF
VALVES DURING THE CUTOFF TIME. YOU CAN CAUSE DAMAGE TO
THE EQUIPMENT WHEN YOU OPEN THE CUTOFF VALVE WITHOUT THE
PRESSURE.
(b)
Close the pitot cutoff valve to the system when the instrument shows the necessary airspeed.
(c)
Stop for 5 to 6 minutes to permit the system to become stable.
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