(e)
Open the static cutoff valves.
F. The Full-Range Pitot-Static System Leak Test
S 865-005
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 AND THE STATIC PRESSURE CHANGES LESS THAN 5000 FEET 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.
(1) Apply pressure to the pitot-static system equivalent to 25,000 |200 feet of altitude (11.10 |0.10 in. Hg absolute) and 300 |5 knots of airspeed (4.53 |0.16 in. Hg differential).
NOTE: Monitor the differential pressure during this step to make
____
sure that you obey the caution above.
S 865-006
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.
(2)
Close the pitot and static system cutoff valves when the instruments show the necessary altitude and airspeed.
(3)
Stop for 5 to 6 minutes to permit the systems to become stable.
(4)
Write the altitude and airspeed.
(5)
Stop for 1 minute.
S 865-157
(6)
Make sure that the altitude does not go down by more than 400 feet
S 795-007
S 865-158
S 795-008
(0.20 in. Hg).
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S 865-159
(7) Make sure that the airspeed does not go down by more than 5.0 knots
(0.16 in. Hg).
S 865-009
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 AND THE STATIC PRESSURE CHANGES LESS THAN 5000 FEET 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.
(8)
Open the pitot and static system cutoff valves.
S 865-263
(9)
Put the pitot-static systems to ambient pressure.
NOTE: You must release the vacuum from the cutoff valves slowly.
____
G. Put the Airplane to Its Usual Condition
S 085-010
CAUTION: DO NOT DISCONNECT THE PNEUMATIC TEST SET WHEN THE PITOT-STATIC
_______ SYSTEM IS NOT AT AMBIENT PRESSURE. YOU CAN CAUSE DAMAGE TO THE EQUIPMENT.
(1)
Remove the pneumatic test set from the static port test adapters.
S 085-011
(2)
Remove the static port test adapter and seal from the static pressure ports.
WARNING: FAILURE TO REMOVE THE VINYL ADHESIVE TAPE FROM THE STATIC
_______ PORTS BEFORE FLIGHT MAY CAUSE LARGE ERRORS IN AIRSPEED SENSING AND ALTITUDE SENSING SIGNALS, WHICH MAY LEAD TO LOSS OF SAFE FLIGHT.
CAUTION: MAKE SURE THAT YOU REMOVE ALL OF THE PIECES OF TAPE FROM
_______ EACH STATIC PORT. THE SYSTEM WILL NOT OPERATE CORRECTLY WHEN THE TAPE IS IN ITS POSITION.
(a)
Remove the vinyl adhesive tape from the left alternate static pressure port.
(b)
Remove the test adapter from the right alternate static pressure port.
(c)
Remove the test adapter from the left dedicated static pressure port.
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(d) Remove the test adapter from the right dedicated static pressure port.
S 425-534
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