(2)
After a major airframe overhaul.
(3)
After you remove a fitting.
F. The low-range leak test of the static system makes sure that the static systems do not have leaks at an altitude 5,000 feet above field elevation. The low-range leak test uses lower pressure and bleeds the unpressurized pitot port to ambient pressure. A low-range leak test is not necessary for the 4 pitot systems.
G. You can do the low-range static system leak test to quickly make sure that the static system is serviceable.
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H. A full-range leak test is necessary for these conditions:
(1)
When there is a leak.
(2)
When the result of a low-range leak test is unsatisfactory.
I. You do not have to do a leak test when you connect a quick-disconnect fitting.
J. Visually examine the quick-disconnect for a full seal.
K. You must do a full-range leak test when you cannot make sure that the quick-disconnect has a full seal.
L. These general instructions apply to the pitot-static system leak test.
(1)
The rate of applied vacuum to a static system must be 5000 feet or less for each minute.
(2)
The release of the vacuum from a static system must be 5000 or less for each minute.
(3)
The rate of applied pressure to a pitot system must be 300 knots or less for each minute.
(4)
The release of pressure from a pitot system must be 300 knots or less for each minute.
(5)
Absolute pressure in the pitot system must be equal or higher than the pressure in the static system.
(6)
The differential pressure between the pitot and static systems must not be larger than 10.19 inches of mercury.
(7)
The absolute pressure applied to a static system must not be larger than ambient pressure when an instrument is connected to that static system.
(8)
The pressure in a static system must not be larger than 32.10 inches of mercury.
(9)
Do one of these steps when you do a full-range leak test:
(a)
Make sure that the pitot lines to the elevator feel computer are disconnected.
(b)
Connect the pneumatic test set to dedicated static pressure ports.
(10)
Do not connect or disconnect equipment or indicators when you apply pressure or vacuum to the pitot-static system.
(11)
The drain fittings must stay in their positions during the leak test.
(12)
Make sure that the quick-disconnect fittings stay during the leak test.
(13)
Make sure that the left and right AOA vanes are in the same position for all of the test.
CAUTION: MAKE SURE THAT YOU DO NOT APPLY ELECTRICAL POWER TO THE
_______
PITOT-STATIC PROBE HEATERS. YOU CAN CAUSE DAMAGE THE
PITOT-STATIC PROBES.
(14)
Make sure that the pitot-static probe heat is off during the test.
(15)
Make sure that the autopilot system is off during the test.
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(16)
Make sure that the seals that you use on the static ports do not extend into the port.
(17)
Make sure that the surfaces around the static ports are not damaged when you remove the seals.
(18)
Make sure that you install flow restrictors between the cutoff valve and the pitot-static system.
(19)
Do the these steps before you disconnect a pitot-static fitting:
(a)
Remove the Witness Identification Mark from the pitot-static fitting
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