Installation of the MLG Uplock Pin with the Use of Liquid Nitrogen

TASK 32-11-11-400-003-B-01
Installation of the MLG Uplock Pin with the Use of Liquid Nitrogen

WARNING: PUT THE SAFETY DEVICES AND THE WARNING NOTICES IN POSITION BEFORE YOU START A TASK ON OR NEAR:

THE FLIGHT CONTROLS
THE FLIGHT CONTROL SURFACES
THE LANDING GEAR AND THE RELATED DOORS
COMPONENTS THAT MOVE.

MOVEMENT OF COMPONENTS CAN KILL OR CAUSE INJURY TO PERSONS AND/OR CAN CAUSE DAMAGE TO THE EQUIPMENT.

WARNING: BE CAREFUL WHEN YOU USE CONSUMABLE MATERIALS. OBEY THE MATERIAL MANUFACTURER'S INSTRUCTIONS AND YOUR LOCAL REGULATIONS.

ZONE: 731
ZONE: 741

1. Reason for the Job

NOTE: This task is an alternative to the AMM task 32-11-11-400-003-B for the Installation of the MLG Uplock Pin.

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

REFERENCE	QTY	DESIGNATION
No specific	AR	GOGGLES - PROTECTIVE
No specific	AR	SAFETY BARRIER(S)
No specific	AR	WARNING NOTICE(S)
No specific	Torque wrench: range to between 2.9 and 2.1 m.daN (21.39 and 15.49 lbf.ft )

B. Consumable Materials

REFERENCE	DESIGNATION
(Material No.06AAC5)	Polysulfide Sealant-General Purpose Interfay Landing Gear
(Material No.06LDG6)	Non Hardening Jointing Putty-High Temp. Area - Hydraulic
(Material No.08BAA9)	Non Aqueous Cleaner-General - -
(Material No.14QFB1)	Wire-Locking Dia: 0.8 mm CRES Nickel Alloy -
(Material No.14SBA1)	Textile-Lint free Cotton -
(Material No.14VGC2)	Individual Compound-- Nitrogen Liquid

C. Work Zones and Access Panels

ZONE/ACCESS	ZONE DESCRIPTION
731	L.H MAIN GEAR
741	R.H MAIN GEAR

D. Expendable Parts

FIG.ITEM	DESIGNATION	IPC-CSN
10	PIN	AIPC 32-11-11-82-170
2	PIN	AIPC 32-11-11-82-170
10	COTTER PINS	AIPC 32-11-85-82-170
2	COTTER PIN	AIPC 32-11-85-82-170

E. Referenced Information

REFERENCE	DESIGNATION
TASK 20-28-00-720-005-A	Check of the Electrical Bonding of the Different Components (but not the Fluid Systems and Components Installed on Composite materials)
TASK 29-00-00-864-001-A	Put the Related Hydraulic System in the Depressurized Configuration before Maintenance Action
TASK 29-23-00-860-001-A	Disconnection of the Isolation Coupling of the Power Transfer Unit (PTU)
TASK 29-23-00-860-002-A	Connection of the Isolation Coupling of the Power Transfer Unit (PTU)
TASK 32-00-00-481-001-A	Installation of the Safety Devices on the Landing Gears
TASK 32-00-00-860-001-A	Flight Configuration Precautions with Electrical Power
TASK 32-00-00-860-001-A-01	Flight Configuration Precautions without Electrical Power
TASK 32-00-00-860-002-A	Ground Configuration after Flight Configuration with Electrical Power
TASK 32-00-00-860-002-A-01	Ground Configuration after Flight Configuration without Electrical Power
TASK 32-31-00-820-003-A	Adjustment of the MLG Uplock
MLG Uplock Pin - Location and Detail
Tools for Installation of the MLG Uplock Pin

3. Job Set-up
Subtask 32-11-11-941-067-A ** ON A/C NOT FOR ALL

A. Safety Precautions
(1) Make sure that the SAFETY BARRIER(S) are in position.
(2) On panel 400VU:
(a) Make sure that the landing-gear control lever is in the DOWN position
(b) Make sure that WARNING NOTICE(S) are in position to tell persons not to operate the landing gear.
(c) Make sure that the WARNING NOTICE(S) are in position to tell persons not to operate the main gear doors.
(3) Make sure that a WARNING NOTICE(S) is in the cockpit to tell persons not to pressurize the Green hydraulic system.
(4) Make sure that the ground safety locks are installed on the landing gear (Ref. AMM TASK 32-00-00-481-001).
(5) For installation of the uplock pin (6), use a small quantity of Individual Compound-- Nitrogen Liquid (Material No.14VGC2) .

NOTE: Liquid nitrogen:

Is very cold -196 deg.C (-320.80 deg.F)
Is not poisonous
Does not cause corrosion
Is not flammable
Is a bad electrical conductor.

(a) Obey these precautions when you use uplock pin (6) and liquid nitrogen:
1 Keep the uplock pin (6) and the liquid nitrogen in a correct container (workbox).
2 Do the work in an area open to the air.
3 Do not touch your skin.
4 Use gloves when you touch cold parts.
5 Do not put your hands into liquid nitrogen.
6 Use GOGGLES - PROTECTIVE.
7 Use correct tools.
(b) If liquid nitrogen spills:
1 Stay clear of the spilled liquid as it will dry quickly.
2 Immediately remove clothes or shoes soaked with liquid nitrogen.
3 Flush your skin/eyes with warm water and get medical aid immediately, if you get the liquid nitrogen on your skin/eyes.

Subtask 32-11-11-860-085-A ** ON A/C NOT FOR ALL

B. Aircraft Maintenance Configuration
(1) If applicable, make sure that the flight configurations were obeyed (Ref. AMM TASK 32-00-00-860-001).
(2) Make sure that the Green and Yellow hydraulic systems are depressurized (Ref. AMM TASK 29-00-00-864-001).
(3) If applicable, make sure that the isolation coupling on the PTU is disconnected (Ref. AMM TASK 29-23-00-860-001).
(4) Make sure that the access platform is in position below the applicable zone 731(741).

Subtask 32-11-11-865-073-A ** ON A/C NOT FOR ALL

C. Make sure that this(these) circuit breaker(s) is(are) open, safetied and tagged:

PANEL	DESIGNATION	FIN	LOCATION
** ON A/C NOT FOR ALL
49VU	L/G/LGCIU/SYS1/NORM	1GA	C09
** ON A/C NOT FOR ALL
121VU	LGCIU/BAT SPLY/SYS2	59GA	R33
121VU	LGCIU/BAT SPLY/SYS1	58GA	R32
** ON A/C NOT FOR ALL
121VU	HYDRAULIC/LGCIU/SYS2	2GA	Q35
121VU	HYDRAULIC/LGCIU/SYS1/GRND SPLY	52GA	Q34
** ON A/C NOT FOR ALL
121VU	LGCIU/BAT SPLY/SYS2	59GA	R32
121VU	LGCIU/BAT SPLY/SYS1	58GA	R31

4. Procedure
Subtask 32-11-11-420-095-A ** ON A/C NOT FOR ALL

A. Preparation for Installation
(1) Use a Textile-Lint free Cotton - (Material No.14SBA1) made moist with Non Aqueous Cleaner-General - - (Material No.08BAA9) to clean the components and the component interface.
(2) Make sure that the parts retained from the removed component are clean and in the correct condition.
(3) Apply Non Hardening Jointing Putty-High Temp. Area - Hydraulic (Material No.06LDG6) to:

The interface of the uplock pin (6) and the MLG attachment lugs where you install the uplock pin (6)
The mating surface of the ground stud (4) and the threads of the ground stud bolt (7)
The shank and threads of the bolts (8) and (9).

(4) Use the tools that follow to install the uplock pin (6):

Tools for Installation of the MLG Uplock Pin ** ON A/C NOT FOR ALL

A workbox to put the uplock pin (6) fully into liquid nitrogen
A pair of gloves to touch the cold uplock pin (6)
Tongs to remove the uplock pin (6) from the liquid nitrogen.

Subtask 32-11-11-420-096-A ** ON A/C NOT FOR ALL

B. Installation of the MLG Uplock Pin

WARNING: USE PROTECTIVE GOGGLES AND GLOVES WHEN YOU REMOVE OR INSTALL LOCKWIRE. EACH TIME YOU CUT LOCKWIRE, REMOVE AND DISCARD IT IMMEDIATELY. LOOSE LOCKWIRE CAN CUT YOU OR MAKE YOU BLIND, AND/OR CAN CAUSE DAMAGE.

(1) Decrease the temperature of the uplock pin (6) and the tongs.
(a) Put the uplock pin (6) fully into the liquid nitrogen in the workbox.
(2) Wait for 10 minutes and install the uplock pin (6):
(a) Use the gloves and the cold tongs to remove the uplock pin (6) from the workbox.
(b) Hold the uplock pin (6) with gloves and put it in position on the MLG attachment lugs.
(c) Install the bolts (9), the washers (12) and the nuts (11).
(d) Install the bolt (8), the washer (1) and the nut (3).
(e) TORQUE the nuts (3) and (11) to between 2.9 and 2.1 m.daN (21.39 and 15.49 lbf.ft )

.
(f) Safety the nut (3) with the new AIPC 32-11-11-82-170 PIN (2) or AIPC 32-11-85-82-170 COTTER PIN (2).
(g) Safety the nuts (11) with the new AIPC 32-11-11-82-170 PIN (10) or AIPC 32-11-85-82-170 COTTER PINS (10).
(h) Install the ground stud bolt (7), the washer (5) and the ground stud (4).
(i) TORQUE the ground stud (4) to between 2.9 and 2.1 m.daN (21.39 and 15.49 lbf.ft )

.
(j) Safety the ground stud (4) to the ground stud bolt (7) with 14QFB1Wire-Locking Dia: 0.8 mm CRES Nickel Alloy -.
(k) Do an electrical bonding test between the MLG pintle-pin bearing and the ground stud (4) (Ref. AMM TASK 20-28-00-720-005):
(l) Make sure that the bonding resistance value is not more than 10 milliohms.

NOTE: If you have to replace the uplock pin (6) because of damage or if the uplock position is not correct, do a check of the uplock adjustment (Ref. AMM TASK 32-31-00-820-003).

Subtask 32-11-11-420-096-B ** ON A/C NOT FOR ALL

B. Installation of the MLG Uplock Pin

.
(j) Safety the ground stud (4) to the ground stud bolt (7) with 14QFB1Wire-Locking Dia: 0.8 mm CRES Nickel Alloy -.
(k) Install the heat shrink tube on the lockwire.
(l) Do an electrical bonding test between the MLG pintle-pin bearing and the ground stud (4) (Ref. AMM TASK 20-28-00-720-005):
(m) Make sure that the bonding resistance value is not more than 10 milliohms.

NOTE: If you have to replace the uplock pin (6) because of damage or if the uplock position is not correct, do a check of the uplock adjustment (Ref. AMM TASK 32-31-00-820-003).

Subtask 32-11-11-390-053-A ** ON A/C NOT FOR ALL

C. Sealant
(1) Apply Polysulfide Sealant-General Purpose Interfay Landing Gear (Material No.06AAC5) to:

The area around the interface between the uplock pin (6) and the MLG attachment lugs
The ends of the ground stud (4), the washer (5) and the head of the ground stud bolt (7)
The ends of the nut (3), the washer (1) and the head of the bolt (8)
The ends of the nuts (11), the washers (12) and the head of the bolts (9).

Subtask 32-11-11-865-074-A ** ON A/C NOT FOR ALL

D. Remove the safety clip(s) and the tag(s) and close this(these) circuit breaker(s):

PANEL	DESIGNATION	FIN	LOCATION
** ON A/C NOT FOR ALL
49VU	L/G/LGCIU/SYS1/NORM	1GA	C09
** ON A/C NOT FOR ALL
121VU	LGCIU/BAT SPLY/SYS2	59GA	R33
121VU	LGCIU/BAT SPLY/SYS1	58GA	R32
** ON A/C NOT FOR ALL
121VU	HYDRAULIC/LGCIU/SYS2	2GA	Q35
121VU	HYDRAULIC/LGCIU/SYS1/GRND SPLY	52GA	Q34
** ON A/C NOT FOR ALL
121VU	LGCIU/BAT SPLY/SYS2	59GA	R32
121VU	LGCIU/BAT SPLY/SYS1	58GA	R31

Subtask 32-11-11-860-086-A ** ON A/C NOT FOR ALL

E. Aircraft Maintenance Configuration
(1) Connect the isolation coupling of the PTU (Ref. AMM TASK 29-23-00-860-002).

CAUTION: YOU MUST CLOSE THE CIRCUIT BREAKERS OPENED FOR AIRCRAFT FLIGHT CONFIGURATION WHEN THE MAINTENANCE WORK IS COMPLETED. DAMAGE TO THE AIRCRAFT CAN OCCUR IF THEY STAY OPEN.

(2) If the flight configuration precautions were obeyed, put the aircraft into the ground configuration (Ref. AMM TASK 32-00-00-860-002).

5. Close-up
Subtask 32-11-11-942-065-A ** ON A/C NOT FOR ALL

A. Removal of Equipment
(1) Remove the SAFETY BARRIER(S).
(2) Remove the WARNING NOTICE(S).
(3) Remove the ground support and maintenance equipment, the special and standard tools and all other items.

[Rev.10 from 2021] 2026.04.01 00:39:57 UTC