CESSNA®
MODEL 525B
MAINTENANCE MANUAL
C.
Copilot (Right) Pitot-Static System Leak Test.
(1)
Make sure the BATTERY switch is in the ON position.
(2)
Do the pitot/static self test on the air data test set.
(a)
Set the test set to the Leak mode.
(3)
Connect the air data test set to one of the copilot static ports (upper left or lower right).
CAUTION:
Do not use transparent tape or paper masking tape. Paper masking
tape or transparent tape are not equivalent substitutes for red vinyl
pressure tape.
(4)
Use red vinyl tape to cover the upper left or lower right static port that is open. Refer to Navigation
- General, Tools and Equipment.
(5)
Connect the portable air data test set to the right pitot tube.
(6)
Push and adjust the BARO knob on the copilot GCU 275 PFD Controller to 29.92 inHg (101.3
kPa).
(7)
Apply the pitot pressure to get an indication of the airspeed to 150 knots, +2 or -2 knots, on the
air data test set.
(8)
Put the air data test set in Leak Check mode.
(a)
If the system does not stabilize, repair leaks.
(9)
On the air data test set put Leak Check to OFF.
(10) Apply pitot pressure until there is an indicated airspeed of 250 knots, +0.5 or -0.5 knot, on the
copilot PFD.
(11) Adjust the static vacuum until there is an indicated altitude of 5000 feet, +22 or -22 feet (1524
m, +7 or -7 m) on the air data test set.
(12) Put the air data test set in Leak check mode.
(a)
If the system does not stabilize, repair leaks.
(13) On the air data test set put Leak Check to OFF.
(14) Adjust static vacuum until there is an indicated altitude of 31,420 feet, +40 or -40 feet (9579 m,
+12 and -12 m) on the air data test set.
(15) If the airplane altimeter does not align with the air data test set altimeter do the steps that follow:
(a)
Bleed the pitot system to 0 knots and the static system to current altitude.
(b)
Examine the static heater port and/or tubing for obstructions or restrictions.
(c)
If necessary, clean the pitot-static system to remove obstructions. Refer to Pitot-Static
Systems - Maintenance Practices.
(16) With the static system at 31,420 feet (9579 m) and the pitot system at 250 knots on the test set
put the test set in Leak Check mode.
NOTE:
With the static system at 31,420 feet (9579 m), a pitot system leak will cause the
airspeed to decrease.
(17) Make sure that within one minute:
(a)
The closed system altimeter indication on the air data test set does not decrease below
31,170 feet (9500 m) within one minute.
(b)
The closed system airspeed indication on the air data test set does not decrease below
245 knots within one minute.
(18) Bleed the pitot and static systems to the ambient pressure at a rate not to exceed 200 knots-
per-minute (370 km/min) and 6000 feet-per-minute (1829 m/min).
(19) If testing is complete, remove the vinyl tape from the ports.
(20) If testing is complete configure the airplane and air data test set to the pretest condition. Refer
D.
Standby Pitot-Static System Leak Test.
NOTE:
The Electronic Standby Indicator ESI-1000 or EFD-750 is used for this test.
(1)
Make sure the BATTERY switch is in the ON position.
(2)
On the ELECTRICAL POWER switch panel put the STBY FLT DISPLAY switch to the ON
position.
34-11-00
Page 609
© TEXTRON AVIATION INC.
Feb 23/2022
ICA-525B-34-00004
Form 2261 Rev 1
