(g)
See that flow restrictors are always placed between cutoff valves and airplane pitot and static systems.
CAUTION: PITOT-STATIC PROBES ARE DELICATE INSTRUMENTS AND
_______ CRITICALLY ALIGNED ON THE AIRPLANE. EXTREME CARE MUST BE EXERCISED WHEN INSTALLING, REMOVING OR HANDLING.
(h) Before performing leakage test on No. 1 and No. 2 auxiliary pitot system: 1) Disconnect and cap pitot lines from stabilizer control
modules (Ref 27-41-04).
On AF 104; AZ 202; plus airplanes
incorporating SB 27-2027,
disconnect and cap pitot lines from elevator feel
computers (Ref 27-31-14).
On LH 004-099; AF 105-199; AZ 203-299; SN ALL; IB 405-499;
MD ALL; GN ALL; AT ALL; VM ALL,
disconnect and cap pitot lines from elevator feel
computers and stabilizer control modules by means of
quick-disconnects at station 2450, LBL 10.
CAUTION: PITOT LINES MUST BE DISCONNECTED, OR ELEVATOR FEEL
_______ COMPUTERS AND STABILIZER CONTROL MODULES COULD BE DAMAGED.
2) On AZ 201-202, 209-211; IB 405,
turn on, or remove magazine from ARINC 542 type flight recorder.
(2) Test Pitot Systems
(a) Connect test equipment as follows: (Fig. 501)
1) Connect pitot (pressure) source in pneumatic test unit through pitot control valve to pitot cutoff valve.
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34-11-00
2) Wet pitot-static probe adapters and connect pitot inlet of upper left pitot-static probe to the pitot cutoff valve through pitot system test gage and flow restrictor.
CAUTION: ENSURE THAT PROBE ADAPTER IS FLUSHED WITH WATER
_______ BEFORE ATTACHING ADAPTER TO PROBE, OR PROBE AND/OR ADAPTER MAY BE DAMAGED. A SOLUTION CONSISTING OF HALF PURE ETHYLENE GLYCOL AND HALF WATER SHOULD BE USED IN FREEZING TEMPERATURES DOWN TO -40.F. TO PREVENT PROBE MISALIGNMENT, TEST HOSES AND ADAPTERS MUST BE SUPPORTED IN SUCH A WAY AS TO ADD NO EXTRA WEIGHT ON PROBES.
3) Seal the pitot chamber drain hole on the bottom of the upper left pitot-static probe with vinyl adhesive tape.
NOTE: You will find the drain hole , approximately 2.25
____
inches, aft of the probe tip.
(b) Test captain's pitot system for leakage.
CAUTION: TO PREVENT INSTRUMENT/EQUIPMENT DAMAGE, KEEP RATE
_______ OF PITOT PRESSURE CHANGE BELOW 300 KNOTS PER MINUTE AND DIFFERENTIAL PRESSURE BETWEEN 0 AND 10 INCHES OF MERCURY.
1) Make sure that test equipment installation is complete and ready for operation.
2) Open cutoff valve. Use pneumatic test unit and pitot control valve to apply pressure of 4.53 (| 0.16) inches of mercury (gage) or 300 (| 5) knots to captain's pitot system as indicated on captain's airspeed indicator or pitot system test gage.
3) When system has stabilized, close pitot cutoff valve. Read and record value being indicated by the captain's airspeed indicator or pitot system test gage.
NOTE: Accuracy of reading and recording pressures must be
____ | 0.03 inch of mercury or | 1 knot.
4) After 1 minute, read and record value indicated on captain's airspeed indicator or pitot system test gage. The pressure must not have decreased by more than 0.16 inch of mercury or 5 knots.
5) Remove adapter and vinyl adhesive tape from upper left pitot-static probe.
CAUTION: TO PREVENT PITOT-STATIC PROBE DAMAGE VISUALLY
_______
CHECK PROBE AND VERIFY THAT NO PIECES OF COLORED
TAPE REMAIN ON PROBE.
EFFECTIVITY
ALL 01.1 Page 512 Oct 25/9834-11-00
(c) Test auxiliary pitot system No. 1 for leakage.
CAUTION: TO PREVENT INSTRUMENT/EQUIPMENT DAMAGE, KEEP RATE
_______ OF PITOT PRESSURE CHANGE BELOW 300 KNOTS PER MINUTE AND DIFFERENTIAL PRESSURE BETWEEN 0 AND 10 INCHES OF MERCURY. TURN ON, OR REMOVE MAGAZINE FROM ARINC 542 FLIGHT RECORDER BEFORE PROCEEDING WITH THIS TEST (REF 31-31-01).
1) Use adapter and drain seal (similar to paragraph (2) (a)) to attach lower left pitot-static probe to pneumatic test unit.
CAUTION: ENSURE THAT PROBE ADAPTER IS FLUSHED WITH WATER
_______ BEFORE ATTACHING ADAPTER TO PROBE, OR PROBE AND/OR ADAPTER MAY BE DAMAGED. A SOLUTION CONSISTING OF HALF PURE ETHYLENE GLYCOL AND HALF WATER SHOULD BE USED IN FREEZING TEMPERATURES DOWN TO -40.F. TO PREVENT PROBE MISALIGNMENT, TEST HOSES AND ADAPTERS MUST BE SUPPORTED IN SUCH A WAY AS TO ADD NO EXTRA WEIGHT ON PROBES.
(3) On LH 082-099; AF 121, 122, 151-199; AZ 231 WITH SB 27-2343; AZ 281-299; AND SN 351-399; MD ALL; GN ALL; AT ALL; VM ALL,plus airplanes incorp SB 27-2297; Open TE FLAP LOAD RELIEF circuit breaker on P12 panel.
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本文链接地址：747飞机维护手册AMM CHAPTER 34 - NAVIGATION 第34章导航1(42)
