(14)
Measure the resistance from pin 3 or 4 and 2 or 5 to the temperature probe case.
(15)
Make sure the resistance is greater than 10 megaohms.
(16)
Measure the resistance of the heater element between pins 1 and 6.
(17)
Make sure the resistance is approximately 20 ohms at ambient temperature between 60 and 90.F.
NOTE: The resistance must be somewhat less at low temperature and
____
somewhat higher at high ambient temperature.
(18)
Measure the resistance from either pin 1 or 6 to the TAT probe case.
(19)
Make sure the resistance is greater than 5 megohms.
(20)
Replace the electrical connector on the TAT probe.
(21)
After thermometers have stabilized, check that temperature indicated at temperature probes number one and two, and indication on flight engineer's total air temperature indicator and TAT readout on TAT/N1 or TAT/EPR limit indicator agree within 2.C.
(22)
Heat total air temperature probe number one and check that TAT reading moves in direction of higher temperatures.
(23)
If initial temperatures were below 0.C, continue to heat probe until temperature reading passes through zero and observe that plus-minus drum trips over to read plus.
(24)
Cool total air temperature probe number one and check that TAT reading moves in direction of lower temperatures.
(25)
If initial temperatures were above 0.C, continue to cool probe until temperature reading passes through zero and observe that plus-minus drum trips over to read minus.
(26)
Repeat above procedure using temperature probe number two and flight engineer's total air temperature indicator.
(27)
Shutdown air supply to aspirated temperature probe.
(28)
Pressurize captain's and first officer's pitot-static systems. Refer to 34-11-00.
(29)
Operate pneumatic test unit to provide required static and pitot pressures in pitot-static system for test point one in Fig. 502.
CAUTION: PITOT PRESSURE MUST ALWAYS BE EQUAL TO OR EXCEED STATIC
_______ PRESSURE. DIFFERENCE MUST NOT EXCEED 10.00 NOR FALL BELOW 0 INCHES-OF-MERCURY, EVEN MOMENTARILY, OR INSTRUMENTS WILL BE DAMAGED.
(30)
Observe that indicated airspeed/mach indicators display, within allowable tolerance, mach number as indicated in Fig. 502 for test point number one.
(31)
Observe that altimeters display, within allowable tolerance, altitude as indicated in Fig. 502 for test point one.
EFFECTIVITY
ALL 02 Page 516 Sep 25/9434-12-00
(32)
Repeat above procedure for test points two through eight of Fig.
502.
(33)
Read temperature indicated on thermometer next to total air temperature probe number one. Using this value of indicated temperature and mach number of 0.500 mach, check Fig. 503 and determine value of true airspeed.
NOTE: Adjust differential pressure until both mach indicators read
____
exactly 0.500 mach.
(34)
Observe that true airspeed indicator displays correct value within tolerances noted in Fig. 503.
(35)
Read temperature indicated on thermometer next to total air temperature probe number two. Using this value of indicated temperature and mach number of 0.500 mach, check Fig. 504 and determine value of static air temperature.
(36)
Observe that static air temperature indicator displays correct value with tolerances noted in Fig. 504.
(37)
Pressurize pitot-static system for test point one of Fig. 502.
(38)
If the CADC's are Boeing P/N 60B00058, on front panel of computer No. 1 and then No. 2, set functional test select switch to DIGITIZER position and depress PUSH-TO-TEST switch. Note that altitude reporting lamps B2, B4 and C2 illuminate and all other lamps are extinguished. Release PUSH-TO-TEST switch.
NOTE: When you test the CADC 1, make sure that the ALT REPORTING
____ SWITCH is set to the 1 position. When you test the CADC 2, make sure that the ALT REPORTING SWITCH is set to the 2 position.
(39)
If the CADC's are Boeing P/N 60B00058, on front panel of computer No. 1 and then No. 2, set functional test select switch to LAMP CHK position and depress PUSH-TO-TEST switch. Note that all 10 altitude reporting lamps illuminate. Release PUSH-TO-TEST switch.
(40)
If the CADC's are Boeing P/N 60B40126, on front panel of computer No. 1 and then No. 2, set functional test select switch to LAMP CHK position and depress button B and hold, then depress button A and hold. All chassis altitude reporting lights and chassis warning lights should illuminate. Release buttons A and B.
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