S 215-150
(8) Examine the pitot-static probe static ports for unwanted materials and rough locations on the inner and outer surfaces (Ref 34-11-01/601).
I. The Alternate Static System Cross-Manifold Test
S 485-514
WARNING: WHEN THE STATIC PORTS ARE COVERED, MAKE SURE THAT CONDITION IS
_______ VISIBLE FROM THE GROUND. FAILURE TO OBSERVE AND REMOVE COVERINGS OVER STATIC PORTS BEFORE FLIGHT MAY CAUSE LARGE ERRORS ON AIRSPEED SENSING AND ALTITUDE SENSING SIGNALS, WHICH MAY LEAD TO LOSS OF SAFE FLIGHT.
CAUTION:_______DO NOT EXTEND THE SEALS INTO THE STATIC PORTS. YOU CAN CAUSE DAMAGE TO THE SURFACE IN THE AREA WHEN YOU REMOVE THE SEALS.
(1) Seal the left and right alternate static pressure ports with vinyl adhesive tape.
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S 485-151
(2) Connect the pneumatic test set to the alternate static system test fitting.
(a)
Connect the static (vacuum) source in the pneumatic test unit through the static control valve to the static cutoff valve.
(b)
Connect the quick-disconnect test fitting of the alternate static system to the static cutoff valve through the static system test gage and flow restrictor.
NOTE: You will find the test fitting on the left side of the
____ airplane above the system drains at STA 400.
(c) Open the static cutoff valve.
S 795-152
(3) Do a test of the alternate static system manifold
CAUTION: MAKE SURE THAT THE PITOT LINE PRESSURE IS EQUIVALENT OR
_______ MORE THAN THE STATIC LINE PRESSURE. KEEP 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.
(a)
Apply vacuum to the alternate static system eqivalent to 100 feet of altitude above field elevation.
(b)
Close the static cutoff valve to the system when the instrument shows the necessary altitude.
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.
(c) Remove the seal from the left alternate static pressure port.
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(d) Make sure that the indication on the test set vacuum gage drops to field elevation.
WARNING:_______ WHEN THE STATIC PORTS ARE COVERED, MAKE SURE THAT
CONDITION IS VISIBLE FROM THE GROUND. FAILURE TO OBSERVE
AND REMOVE COVERINGS OVER STATIC PORTS BEFORE FLIGHT MAY
CAUSE LARGE ERRORS ON AIRSPEED SENSING AND ALTITUDE
SENSING SIGNALS, WHICH MAY LEAD TO LOSS OF SAFE FLIGHT.
(e)
Seal the left alternate static pressure port again.
(f)
Open the static cutoff valve.
CAUTION: MAKE SURE THAT THE PITOT LINE PRESSURE IS EQUIVALENT OR
_______ MORE THAN THE STATIC LINE PRESSURE. KEEP 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.
(g)
Apply vacuum to the alternate static system equivalent to 100 feet of altitude above field elevation.
(h)
Close the static cutoff valve to the system when the instrument shows the necessary altitude.
LOSS OF SAFE FLIGHT.
(i)
Remove the seal from the right alternate static pressure port.
(j)
Make sure that the indication on the test set vacuum gage drops to field elevation.
WARNING:_______ FAILURE TO REMOVE THE VINYL ADHESIVE TAPE FROM THE STATIC
PORTS BEFORE FLIGHT MAY CAUSE LARGE ERRORS IN AIRSPEED
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