Cleaning of 1 out of 3 Pitot Probes

TASK 34-10-00-170-004-A
Cleaning of 1 out of 3 Pitot Probes

WARNING: MAKE SURE THAT THE CIRCUIT BREAKERS RELATED TO THE WEATHER RADAR ARE OPENED, SAFETIED AND TAGGED.

WARNING: BEFORE YOU OPEN PHC CIRCUIT BREAKERS 2DA1(2,3), OPEN PROBE HEATER CIRCUIT-BREAKERS 1DA1(2), 3DA1(2,3), 4DA1(2,3) AND 5DA1(2,3). IF YOU DO NOT OBEY THIS SEQUENCE: - THE PROBES WILL BECOME TOO HOT. - THIS CAN CAUSE DAMAGE TO EQUIPMENT AND INJURY TO MAINTENANCE PERSONNEL.

ZONE: 125
ZONE: 126
FIN: 9DA1
FIN: 9DA2
FIN: 9DA3

1. Reason for the Job
Refer to the MPD TASK: 341300-11
CLEANING OF 1 OUT OF 3 PITOT PROBES.

To remove dust and particles from the pitot probes.

2. Job Set-up Information
A. Fixtures, Tools, Test and Support Equipment

REFERENCE	QTY	DESIGNATION
No specific	1	ACCESS PLATFORM 2M (6 FT)
No specific	AR	NITROGEN COMPRESSED SOURCE 2 BAR (29 PSI) - DRY
No specific	AR	WIRE - NYLON
98D34103004001	2	CLEANER-PITOT PROBE
98F34103003000	1	FLUSHING TOOL-PITOT PROBE

B. Work Zones and Access Panels

ZONE/ACCESS	ZONE DESCRIPTION
125	LATERAL AVIONIC COMPARTMENT
126	LATERAL AVIONIC COMPARTMENT
FOR [9DA1] (PROBE-PITOT, 1)
812
FOR [9DA2] (PROBE-PITOT, 2)
822
FOR [9DA3] (PROBE-PITOT, 3)
812

C. Referenced Information

REFERENCE	DESIGNATION
TASK 10-11-00-555-013-A	Installation of the Aircraft Protection Equipment
TASK 10-11-00-555-014-A	Removal of the Aircraft Protection Equipment
TASK 24-42-00-861-001-A	Energize the Ground Service Network from the External Power
TASK 24-42-00-862-001-A	De-energize the Ground Service Network Supplied from the External Power
TASK 52-41-00-010-002-A	Open the Avionics Compartment Doors for Access
TASK 52-41-00-410-002-A	Close the Avionics Compartment Doors after Access
Check of the Quick-Disconnect Coupling

3. Job Set-up
Subtask 34-10-00-861-063-A

A. Energize the ground service network
(Ref. AMM TASK 24-42-00-861-001).

Subtask 34-10-00-865-084-A

B. Open, safety and tag these circuit breakers in this sequence:

PANEL	DESIGNATION	FIN	LOCATION
** ON A/C ALL
121VU	COM NAV/RADAR/1	5SQ1	K13
** ON A/C NOT FOR ALL
121VU	COM NAV/RADAR/2	5SQ2	K14
** ON A/C ALL
FOR FIN: 9DA1 (PROBEPITOT, 1)
122VU	ANTI ICE/PROBES/1/TAT	1DA1	Z12
49VU	ANTI ICE/PROBES/PITOT/1	3DA1	D02
49VU	ANTI ICE/PROBES/AOA/1	4DA1	D04
122VU	ANTI ICE/PROBES/1/STATIC	5DA1	Z13
FOR FIN: 9DA2 (PROBEPITOT, 2)
122VU	ANTI ICE/PROBES/2/TAT	1DA2	Y15
122VU	ANTI ICE/PROBES/2/PITOT	3DA2	Y14
122VU	ANTI ICE/PROBES/2/AOA	4DA2	Y13
122VU	ANTI ICE/PROBES/2/STATIC	5DA2	Y11
FOR FIN: 9DA3 (PROBEPITOT, 3)
122VU	ANTI ICE/PROBES/3/PITOT	3DA3	Z16
122VU	ANTI ICE/PROBES/3/AOA	4DA3	Z15
122VU	ANTI ICE/PROBES/3/STATIC	5DA3	Z14
FOR FIN: 9DA1 (PROBEPITOT, 1)
49VU	ANTI ICE/PROBES/PHC/1	2DA1	D03
FOR FIN: 9DA2 (PROBEPITOT, 2)
122VU	ANTI ICE/PROBES/PHC/2	2DA2	Y12
FOR FIN: 9DA3 (PROBEPITOT, 3)
122VU	ANTI ICE/PROBES/PHC/3	2DA3	Y16

Subtask 34-10-00-010-067-A

C. Get access to the avionics compartment.
(1) Put the ACCESS PLATFORM 2M (6 FT) in position:

At zone 125 to get access to pitot probe 1 (9DA1) and pitot probe 3 (9DA3)
At zone 126 to get access to pitot probe 2 (9DA2).

(2) Open the applicable access door (Ref. AMM TASK 52-41-00-010-002):
(a) FOR [9DA1] (PROBE-PITOT, 1)

812.

(b) FOR [9DA3] (PROBE-PITOT, 3)

812.

822.

Subtask 34-10-00-860-079-A

D. Connection of the Dry Nitrogen Source

CAUTION: DO NOT CONNECT THE NITROGEN SOURCE TO THE QUICK-DISCONNECT COUPLING OF THE ADM. IF YOU DO, DAMAGE TO THE ISIS INDICATOR WILL OCCUR.

(1) Remove the aircraft protection equipment, if installed (Ref. AMM TASK 10-11-00-555-014).
(2) Disconnect the quick-disconnect coupling from total pitot probe 1 (2 or 3).
(3) Connect 98F34103003000 FLUSHING TOOL-PITOT PROBE to the quick-disconnect coupling of pitot probe 1 (2 or 3). Then connect the flushing tool to a NITROGEN COMPRESSED SOURCE 2 BAR (29 PSI) - DRY.
(4) Attach the hose of the adapter to prevent movement.

4. Procedure
Subtask 34-10-00-170-061-A

A. Cleaning of the Pitot Probe Drain-Holes (for the Thales Pitot Probes)
(1) Blow the nitrogen gas from the NITROGEN COMPRESSED SOURCE 2 BAR (29 PSI) - DRY through the hose at a pressure of 2 -0.35 bar or +0.35 bar (29 -5 psi or +5 psi) for approximately three minutes.
(2) Use the 98D34103004001 CLEANER-PITOT PROBE and the WIRE - NYLON with diameters of 0.7 mm (0.028 in.) and 0.8 MM (0.031 IN.) to clean the drain holes of pitot probe 1 (2, 3):
(a) Use the WIRE - NYLON with a length of 5 mm (0.197 in.) to make sure that it does not touch the metal tool element and the pitot probe.
(b) To make the cleaning of the drain holes easier, first use the WIRE - NYLON with a diameter of 0.7 mm (0.028 in.) and then use the WIRE - NYLON with a diameter of 0.8 MM (0.031 IN.).
(3) Make sure that there is no contamination in the pressurized nitrogen gas at the outlet of pitot probe 1 (2, 3).
(4) Stop the flow of the nitrogen gas.
(5) Disconnect the NITROGEN COMPRESSED SOURCE 2 BAR (29 PSI) - DRY.
(6) Disconnect the 98F34103003000 FLUSHING TOOL-PITOT PROBE from pitot probe 1 (2, 3).
(7) Connect the quick-disconnect coupling to pitot probe 1 (2, 3).
(8) Make sure that you can see the blue ring on the quick-disconnect coupling.
(9) Pull the quick-disconnect coupling to make sure that it is correctly attached.
(10) Make sure that the quick-disconnect coupling is correctly engaged (the pin on the quick-disconnect male part is fully engaged into the groove in the quick-disconnect female part).

Check of the Quick-Disconnect Coupling

Subtask 34-10-00-170-062-A

B. Cleaning of the Pitot Probe Drain-Holes (for the Rosemount Aerospace and Goodrich Pitot Probes)
(1) Blow the nitrogen gas from the NITROGEN COMPRESSED SOURCE 2 BAR (29 PSI) - DRY through the hose at a pressure of 2 -0.35 bar or +0.35 bar (29 -5 psi or +5 psi) for approximately three minutes.
(2) Use the 98D34103004001 CLEANER-PITOT PROBE and the WIRE - NYLON with diameters of 0.6 mm (0.024 in.) and 0.7 mm (0.028 in.) to clean the drain holes of pitot probe 1 (2, 3):
(a) Use the WIRE - NYLON with a length of 5 mm (0.197 in.) to make sure that it does not touch the metal tool element and the pitot probe.
(b) To make the cleaning of the drain holes easier, first use the WIRE - NYLON with a diameter of 0.6 mm (0.024 in.) and then use the WIRE - NYLON with a diameter of 0.7 mm (0.028 in.).
(3) Make sure that there is no contamination in the pressurized nitrogen gas at the outlet of pitot probe 1 (2, 3).
(4) Stop the flow of the nitrogen gas.
(5) Disconnect the NITROGEN COMPRESSED SOURCE 2 BAR (29 PSI) - DRY.
(6) Disconnect the 98F34103003000 FLUSHING TOOL-PITOT PROBE from pitot probe 1 (2, 3).
(7) Connect the quick-disconnect coupling to pitot probe 1 (2, 3).
(8) Make sure that you can see the blue ring on the quick-disconnect coupling.
(9) Pull the quick-disconnect coupling to make sure that it is correctly attached.
(10) Make sure that the quick-disconnect coupling is correctly engaged (the pin on the quick-disconnect male part is fully engaged into the groove in the quick-disconnect female part).

Check of the Quick-Disconnect Coupling

Subtask 34-10-00-170-058-A

C. After the Cleaning Procedure

WARNING: IF YOU DISCONNECT PITOT PROBE 3, OR IF YOU DISCONNECT MORE THAN ONE PITOT PROBE, MAKE SURE THAT A SECOND QUALIFIED MECHANIC DOES A VISUAL INSPECTION OF THE QUICK-DISCONNECT COUPLING CONNECTIONS. THE TWO MECHANICS MUST SIGN OFF THE JOB.

(1) Refer to the table that follows to know if you must do two checks of the quick-disconnect couplings and/or the leak test:

Condition	Two Checks of the Quick-Disconnect Couplings	Leak Test
One pitot drain-hole cleaning ADR 1 or ADR 2	No	No
More than one pitot drain-hole cleaning or ADR 3 drain-hole cleaning	Yes	No

(a) If you must do two checks of the quick-disconnect coupling:

Tell a second qualified mechanic to do a visual inspection of the quick-disconnect coupling (the signature of the two mechanics is mandatory).
Make sure that the quick-disconnect coupling is correctly engaged (the pin located on the quick-disconnect male part must be fully engaged into the groove in the quick-disconnect female part).
Check of the Quick-Disconnect Coupling

(2) Install the aircraft protection equipment, if necessary (Ref. AMM TASK 10-11-00-555-013).

Subtask 34-10-00-865-085-A

D. Remove the safety clips and tags and close these circuit breakers in this sequence:

PANEL	DESIGNATION	FIN	LOCATION
** ON A/C ALL
121VU	COM NAV/RADAR/1	5SQ1	K13
** ON A/C NOT FOR ALL
121VU	COM NAV/RADAR/2	5SQ2	K14
** ON A/C ALL
FOR FIN: 9DA1 (PROBEPITOT, 1)
49VU	ANTI ICE/PROBES/PHC/1	2DA1	D03
FOR FIN: 9DA2 (PROBEPITOT, 2)
122VU	ANTI ICE/PROBES/PHC/2	2DA2	Y12
FOR FIN: 9DA3 (PROBEPITOT, 3)
122VU	ANTI ICE/PROBES/PHC/3	2DA3	Y16
FOR FIN: 9DA1 (PROBEPITOT, 1)
122VU	ANTI ICE/PROBES/1/TAT	1DA1	Z12
49VU	ANTI ICE/PROBES/PITOT/1	3DA1	D02
49VU	ANTI ICE/PROBES/AOA/1	4DA1	D04
122VU	ANTI ICE/PROBES/1/STATIC	5DA1	Z13
FOR FIN: 9DA2 (PROBEPITOT, 2)
122VU	ANTI ICE/PROBES/2/TAT	1DA2	Y15
122VU	ANTI ICE/PROBES/2/PITOT	3DA2	Y14
122VU	ANTI ICE/PROBES/2/AOA	4DA2	Y13
122VU	ANTI ICE/PROBES/2/STATIC	5DA2	Y11
FOR FIN: 9DA3 (PROBEPITOT, 3)
122VU	ANTI ICE/PROBES/3/PITOT	3DA3	Z16
122VU	ANTI ICE/PROBES/3/AOA	4DA3	Z15
122VU	ANTI ICE/PROBES/3/STATIC	5DA3	Z14

5. Close-up
Subtask 34-10-00-410-067-A

A. Close Access
(1) Make sure that the work area is clean and clear of tools and other items.
(2) Close the applicable access door (Ref. AMM TASK 52-41-00-410-002):
(a) FOR [9DA1] (PROBE-PITOT, 1)

812.

(b) FOR [9DA3] (PROBE-PITOT, 3)

812.

822.

(3) Remove the access platform(s).

Subtask 34-10-00-862-064-A

B. De-energize the ground service network
(Ref. AMM TASK 24-42-00-862-001).

[Rev.10 from 2021] 2026.04.02 07:24:44 UTC