FAA Advisory Circular 43.13-1B
Acceptable Methods, Techniques, and Practices
Aircraft Inspection and Repair
AC 43.13-1B | 12. Aircraft Avionics Systems | 4. Pitot/Static System | 12-59. Test Pitot System
9/27/01
b. After the conclusion of the leak test,
return the system to its normal flying configu
ration. Remove tape from static ports and pitot
drain holes and replace the drain plug.
12-58. STATIC SYSTEM TESTS must
comply with the static system tests required by
14 CFR 91.411 and be performed by an appro
priately-rated repair station with the appropri
ate test equipment.
If the manufacturer has not issued instructions
for testing static systems, the following may be
used:
a. Connect the test equipment directly
to the static ports, if practicable. Otherwise,
connect to a static system drain or tee connec
tion and seal off the static ports. If the test
equipment is connected to the static system at
any point other than the static port, it should be
made at a point where the connection may be
readily inspected for system integrity. Observe
maintenance precautions given in paragraph
12-60 of this section.
AC 43.13-1B CHG 1
structions for testing pitot systems, the fol
lowing may be used:
a. Seal the drain holes and connect the
pitot pressure openings to a tee to which a
source of pressure and manometer or reliable
indicator is connected.
b. Restrain hoses that can whip due to
applied pressure.
c. Apply pressure to cause the airspeed
indicator to indicate 150 knots (differential
pressure 1.1 inches of mercury or 14.9 inches
of water), hold at this point and clamp off the
source of pressure. After 1 minute, the leakage
should not exceed 10 knots (decrease in differ
ential pressure of approximately 0.15 inches
of mercury or 2.04 inches of water).
CAUTION: To avoid rupturing the
diaphragm of the airspeed indicator,
apply pressure slowly and do not
build up excessive pressure in the line.
Release pressure slowly to avoid dam-
aging the airspeed indicator.
b. Do not blow air through the line to
ward the instrument panel. This may seriously
damage the instruments. Be sure to disconnect
the instrument lines so no pressure can reach
the instruments.
c. Apply a vacuum equivalent to 1,000
feet altitude, (differential pressure of approxi
mately 1.07 inches of mercury or 14.5 inches
of water) and hold.
d. After 1 minute, check to see that the
leak has not exceeded the equivalent of 100
feet of altitude (decrease in differential pres
sure of approximately 0.0105 inches of mer
cury or 1.43 inches of water).
12-59. TEST PITOT SYSTEM in accor
dance with the aircraft manufacturer’s instruc
tions. If the manufacturer has not issued in
d. If the airspeed indicator reading de-
clines, check the system for leaky hoses and
loose connections.
e. Inspect the hoses for signs of deterio
ration, particularly at bends and at the connec
tion points to the pitot mast and airspeed indi
cator. Replace hoses that are cracked or hard
ened with identical specification hoses. Any
time a hose is replaced, perform a pressure
check.
Warning: Do not apply suction to pi-
tot lines.
12-60. MAINTENANCE PRECAUTIONS.
Observe the following precautions in all pitot
static system leak testing:
Par 12-57
Page 12-21