DOC AIRBUS | AMM A320FInstallation of the Aerodynamic Strake on the Fan Cowl Door [CFMB]
TASK 71-13-15-400-001-A
Installation of the Aerodynamic Strake on the Fan Cowl Door
1. Reason for the Job
A. Fixtures, Tools, Test and Support Equipment
B. Consumable Materials
C. Work Zones and Access Panels
D. Referenced Information
3. Job Set-up
Subtask 71-13-15-860-050-A ** ON A/C NOT FOR ALL
Subtask 71-13-15-110-050-A ** ON A/C NOT FOR ALL
Subtask 71-13-15-410-050-A ** ON A/C NOT FOR ALL
[Rev.10 from 2021]
2026.04.02 07:30:09 UTC
Installation of the Aerodynamic Strake on the Fan Cowl Door
1. Reason for the Job
NOTE: For aircraft A320, strakes must be installed on the inner side only.
For aircraft A318, A319, A321, strakes must be installed on both sides.
2. Job Set-up InformationFor aircraft A318, A319, A321, strakes must be installed on both sides.
A. Fixtures, Tools, Test and Support Equipment
B. Consumable Materials
| REFERENCE | DESIGNATION |
|---|---|
| (Material No.CP2185) | masking tape 3M 202 |
| (Material No.CP2240) | scotch-brite type A CFS |
| (Material No.CP2244) | primer 1200 |
| (Material No.CP2288) | liquid shim |
| (Material No.CP2428) | PR 1422A |
| (Material No.CP2497) | DC93-006 |
| (Material No.CP2673) | release agent |
| (Material No.14DDB1) | Release Agent-- PTFE Loaded - |
| ZONE/ACCESS | ZONE DESCRIPTION |
|---|---|
| FOR [1000EM1] (ENGINE-1) | |
| 437AL, 438AR | |
| FOR [1000EM2] (ENGINE-2) | |
| 447AL, 448AR | |
| REFERENCE | DESIGNATION |
|---|---|
| TASK 71-13-00-010-040-B | Opening of the Fan Cowl Doors |
| TASK 71-13-00-410-040-B | Closing of the Fan Cowl Doors |
Fan Cowl-Door Aerodynamic-StrakeSubtask 71-13-15-860-050-A ** ON A/C NOT FOR ALL
A. Aircraft Maintenance Configuration
(1) On the center pedestal, on the ENG panel 115VU, make sure that a WARNING NOTICE(S) is in position to tell persons not to start the engine.
(2) On the overhead maintenance panel 50VU, make sure that the ON legend of the ENG/FADEC GND PWR/1(2) pushbutton switch is off. Make sure that a WARNING NOTICE(S) is in position to tell persons not to energize the FADEC 1(2).
(3) Make sure that the ACCESS PLATFORM 1M(3 FT) is in position.
Subtask 71-13-15-010-051-A ** ON A/C NOT FOR ALL (1) On the center pedestal, on the ENG panel 115VU, make sure that a WARNING NOTICE(S) is in position to tell persons not to start the engine.
(2) On the overhead maintenance panel 50VU, make sure that the ON legend of the ENG/FADEC GND PWR/1(2) pushbutton switch is off. Make sure that a WARNING NOTICE(S) is in position to tell persons not to energize the FADEC 1(2).
(3) Make sure that the ACCESS PLATFORM 1M(3 FT) is in position.
B. Get Access
(1) Make sure that the fan cowl doors are open: (Ref. AMM TASK 71-13-00-010-040)
(a) FOR [1000EM1] (ENGINE-1)
(b) FOR [1000EM2] (ENGINE-2)
4. Procedure(1) Make sure that the fan cowl doors are open: (Ref. AMM TASK 71-13-00-010-040)
(a) FOR [1000EM1] (ENGINE-1)
(b) FOR [1000EM2] (ENGINE-2)
Subtask 71-13-15-110-050-A ** ON A/C NOT FOR ALL
A. Prepare the mating surfaces of the strake (10), the bonding strap, the back plate (15), the bolts (5 and 30), the washers (20), and the nuts (25) for the electrical bond.
(1) Use a scotch-brite type A CFS (Material No.CP2240) pad to remove all scratches and burrs that are not more than 0.01 (0.25 mm) deep as follows:
(a) The surfaces of the bolts (5 and 30) where they will touch the bolt holes of the strake (10).
(b) The surfaces of the bolt holes of the strake (10) where the bolts (5 and 30) will touch.
(c) The mating surfaces of the washers (20).
(d) The mating surfaces of the nuts (25).
(e) The surface of the bonding strap where the back plate (15) will touch. Make an area smooth that is 0.25 in. (6,35 mm) larger than the diameter of the back plate (15).
(f) The surface of the back plate (15) where the bonding strap will touch. Make an area smooth that is 0.25 in. (6,35 mm) larger than the surface of the bonding strap.
(g) The surface of the back plate (15) where the washers (20) will touch. Make an area smooth that is 0.25 in. (6,35 mm) larger than the diameter of the washers (20).
(3) Do an electrical bond resistance check.
(a) Put the strake (10) and the back plate (15) on the fan cowl.
(b) Install the bolts (5 and 30), the washers (20), and the nuts (25) at the two forward and two aft positions.
(c) TORQUE the nuts (25) to between 25 and 20 lbf.in (0.28 and 0.23 m.daN )
.
(d) Put one lead of the OHMMETER MULTIRANGE on the head of a bolt (5) that goes through the bonding strap.
(e) Put the other lead of the OHMMETER MULTIRANGE on the surface of the bonding strap.
(f) If the resistance is more than 0.0025 ohm, remove the fasteners and clean the mating surfaces again. Do this procedure until the resistance is 0.0025 ohms or less.
(g) Remove the nuts (25), the washers (20), the bolts (5 and 30), and the strake (10) from the fan cowl.
Subtask 71-13-15-420-050-A ** ON A/C NOT FOR ALL (1) Use a scotch-brite type A CFS (Material No.CP2240) pad to remove all scratches and burrs that are not more than 0.01 (0.25 mm) deep as follows:
(a) The surfaces of the bolts (5 and 30) where they will touch the bolt holes of the strake (10).
(b) The surfaces of the bolt holes of the strake (10) where the bolts (5 and 30) will touch.
(c) The mating surfaces of the washers (20).
(d) The mating surfaces of the nuts (25).
(e) The surface of the bonding strap where the back plate (15) will touch. Make an area smooth that is 0.25 in. (6,35 mm) larger than the diameter of the back plate (15).
(f) The surface of the back plate (15) where the bonding strap will touch. Make an area smooth that is 0.25 in. (6,35 mm) larger than the surface of the bonding strap.
(g) The surface of the back plate (15) where the washers (20) will touch. Make an area smooth that is 0.25 in. (6,35 mm) larger than the diameter of the washers (20).
WARNING:
BE CAREFUL WHEN YOU USE CONSUMABLE MATERIALS. OBEY THE MATERIAL MANUFACTURER'S INSTRUCTIONS AND YOUR LOCAL REGULATIONS.
(2) Clean the mating surfaces of the strake (10), the bonding strap, the back plate (15), the bolts (5 and 30), the washers (20), and the nuts (25) with a clean, lint free cotton cloth and solvent. Make the surfaces dry with a clean, dry, lint free cotton cloth before the solvent becomes dry. (3) Do an electrical bond resistance check.
(a) Put the strake (10) and the back plate (15) on the fan cowl.
(b) Install the bolts (5 and 30), the washers (20), and the nuts (25) at the two forward and two aft positions.
(c) TORQUE the nuts (25) to between 25 and 20 lbf.in (0.28 and 0.23 m.daN )
. (d) Put one lead of the OHMMETER MULTIRANGE on the head of a bolt (5) that goes through the bonding strap.
(e) Put the other lead of the OHMMETER MULTIRANGE on the surface of the bonding strap.
(f) If the resistance is more than 0.0025 ohm, remove the fasteners and clean the mating surfaces again. Do this procedure until the resistance is 0.0025 ohms or less.
(g) Remove the nuts (25), the washers (20), the bolts (5 and 30), and the strake (10) from the fan cowl.
B. Install the aerodynamic strake
(2) Prepare the mating surfaces of the strake (10) and the fan cowl for installation of the strake (10).
(a) Put the strake (10) in to position on the fan cowl.
(b) Put masking tape 3M 202 (Material No.CP2185) on the fan cowl around the edges of the strake (10).
(c) Remove the strake (10).
(3) Put the strake (10) and the back plate (15) on the fan cowl.
(4) Install the bolts (5 and 30), the washers (20), and the nuts (25).
(5) TORQUE the nuts (25) to between 25 and 20 lbf.in (0.28 and 0.23 m.daN ).
(6) Remove the masking tape 3M 202 (Material No.CP2185) from the fan cowl before the liquid shim cures.
(7) Remove unwanted liquid shim before it cures.
(8) Let the liquid shim cure. Refer to the manufacturer's instructions.
Subtask 71-13-15-110-051-A ** ON A/C NOT FOR ALL NOTE: The procedure to install the aerodynamic strake on the left or the right fan cowl is the same.
(1) If necessary, remove the sealing compound from the strake fastener holes. Use a PLASTIC DOWEL with a diameter smaller than the fastener hole to push the sealant out of the holes. (2) Prepare the mating surfaces of the strake (10) and the fan cowl for installation of the strake (10).
(a) Put the strake (10) in to position on the fan cowl.
(b) Put masking tape 3M 202 (Material No.CP2185) on the fan cowl around the edges of the strake (10).
(c) Remove the strake (10).
WARNING:
BE CAREFUL WHEN YOU USE CONSUMABLE MATERIALS. OBEY THE MATERIAL MANUFACTURER'S INSTRUCTIONS AND YOUR LOCAL REGULATIONS.
(d) Clean the surface of the fan cowl inside the masking tape border with a clean, lint free cotton cloth and solvent. Make the surface dry with a clean, dry, lint free cotton cloth before the solvent becomes dry. WARNING:
BE CAREFUL WHEN YOU USE CONSUMABLE MATERIALS. OBEY THE MATERIAL MANUFACTURER'S INSTRUCTIONS AND YOUR LOCAL REGULATIONS.
(e) Apply release agent (Material No.CP2673) or Release Agent-- PTFE Loaded - (Material No.14DDB1) MS-122AD to the surface of the strake (10) that will touch the fan cowl. Refer to the manufacturers instructions. WARNING:
BE CAREFUL WHEN YOU USE CONSUMABLE MATERIALS. OBEY THE MATERIAL MANUFACTURER'S INSTRUCTIONS AND YOUR LOCAL REGULATIONS.
(f) Apply liquid shim liquid shim (Material No.CP2288) to the fan cowl inside the masking tape border. Refer to the manufacturer's instructions. (3) Put the strake (10) and the back plate (15) on the fan cowl.
(4) Install the bolts (5 and 30), the washers (20), and the nuts (25).
(5) TORQUE the nuts (25) to between 25 and 20 lbf.in (0.28 and 0.23 m.daN )
. (6) Remove the masking tape 3M 202 (Material No.CP2185) from the fan cowl before the liquid shim cures.
(7) Remove unwanted liquid shim before it cures.
(8) Let the liquid shim cure. Refer to the manufacturer's instructions.
C. Apply the sealants.
(1) Apply PR 1422A (Material No.CP2428) or PR1828 (faster cure alternate for PR1422A) to prevent moisture on
(c) Let the sealant cure. Refer to the manufacturers instructions.
(2) Apply DC93-006 (Material No.CP2497) to make an aerodynamic surface over the heads of the bolts (5).
(d) Let the sealant cure. Refer to the manufacturer's instructions.
5. Close-up(1) Apply PR 1422A (Material No.CP2428) or PR1828 (faster cure alternate for PR1422A) to prevent moisture on
WARNING:
BE CAREFUL WHEN YOU USE CONSUMABLE MATERIALS. OBEY THE MATERIAL MANUFACTURER'S INSTRUCTIONS AND YOUR LOCAL REGULATIONS.
(a) Clean the edges of the bonding strap where it touches the back plate (15) with a clean, lint free cotton cloth and solvent. Make the surfaces dry with a clean, dry, lint free cotton cloth before the solvent becomes dry. WARNING:
BE CAREFUL WHEN YOU USE CONSUMABLE MATERIALS. OBEY THE MATERIAL MANUFACTURER'S INSTRUCTIONS AND YOUR LOCAL REGULATIONS.
CAUTION:
DO NOT APPLY SEALANT BETWEEN THE BONDING SURFACES.
(b) Apply sealant to the edges of the bonding strap where it touches the back plate (15). Push the sealant into the gap on the under side of the back plate (15). (c) Let the sealant cure. Refer to the manufacturers instructions.
(2) Apply DC93-006 (Material No.CP2497) to make an aerodynamic surface over the heads of the bolts (5).
WARNING:
BE CAREFUL WHEN YOU USE CONSUMABLE MATERIALS. OBEY THE MATERIAL MANUFACTURER'S INSTRUCTIONS AND YOUR LOCAL REGULATIONS.
(a) Clean the heads of the bolts (5 and 30) and the holes of the strake (10) where you will apply the sealant with a clean, lint free cotton cloth and solvent. Make the surfaces dry with a clean, dry, lint free cotton cloth before the solvent becomes dry. WARNING:
BE CAREFUL WHEN YOU USE CONSUMABLE MATERIALS. OBEY THE MATERIAL MANUFACTURER'S INSTRUCTIONS AND YOUR LOCAL REGULATIONS.
(b) Apply primer primer 1200 (Material No.CP2244) to the heads of the bolts (5 and 30) and the holes of the strake (10) where you will apply the sealant (Material No. CP2497). Refer to the manufacturers instructions. WARNING:
BE CAREFUL WHEN YOU USE CONSUMABLE MATERIALS. OBEY THE MATERIAL MANUFACTURER'S INSTRUCTIONS AND YOUR LOCAL REGULATIONS.
(c) Apply DC93-006 (Material No.CP2497) to the heads of the bolts (5 and 30) to make a aerodynamic surface with the external surface of the strake (10). (d) Let the sealant cure. Refer to the manufacturer's instructions.
Subtask 71-13-15-410-050-A ** ON A/C NOT FOR ALL
A. Close Access
(1) Make sure that the work area is clean and clear of tools and other items.
(2) Close the fan cowl doors: (Ref. AMM TASK 71-13-00-410-040)
(a) FOR [1000EM1] (ENGINE-1)
(b) FOR [1000EM2] (ENGINE-2)
(3) Remove the WARNING NOTICE(S).
(4) Remove the access platform(s).
(1) Make sure that the work area is clean and clear of tools and other items.
(2) Close the fan cowl doors: (Ref. AMM TASK 71-13-00-410-040)
(a) FOR [1000EM1] (ENGINE-1)
(b) FOR [1000EM2] (ENGINE-2)
(3) Remove the WARNING NOTICE(S).
(4) Remove the access platform(s).