DOC AIRBUS | AMM A320FInstallation of the Aerodynamic Strake on the Fan Cowl Door [CFMI]
TASK 71-13-15-400-040-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 71-13-15-860-051-B ** ON A/C NOT FOR ALL
Subtask 71-13-15-110-052-B ** ON A/C NOT FOR ALL
Subtask 71-13-15-410-051-B ** ON A/C NOT FOR ALL
[Rev.10 from 2021]
2026.04.01 02:22:38 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 A319, A321, strakes must be installed on both sides.
2. Job Set-up InformationFor aircraft A319, A321, strakes must be installed on both sides.
A. Fixtures, Tools, Test and Support Equipment
B. Consumable Materials
| REFERENCE | DESIGNATION |
|---|---|
| primer 1200 | |
| silicone sealant DC93-006 | |
| (Material No.CP2185) | masking tape 3M 202 |
| (Material No.CP2240) | scotch-brite type A CFS |
| (Material No.CP2288) | liquid shim |
| (Material No.CP2428) | PR 1422A |
| (Material No.CP2673) | release agent |
| ZONE/ACCESS | ZONE DESCRIPTION |
|---|---|
| FOR [1000EM1] (ENGINE-1) | |
| 437AL, 438AR | |
| FOR [1000EM2] (ENGINE-2) | |
| 447AL, 448AR | |
| REFERENCE | DESIGNATION |
|---|---|
| TASK 71-13-00-010-040-A | Opening of the Fan Cowl Doors |
| TASK 71-13-00-410-040-A | Closing of the Fan Cowl Doors |
Fan Cowl Door StrakeSubtask 71-13-15-860-051-B ** 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 71-13-15-010-053-B ** 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)
(2) FOR [1000EM1] (ENGINE-1)
437AL 438AR
(3) FOR [1000EM2] (ENGINE-2)
447AL 448AR
4. Procedure(1) Make sure that the fan cowl doors are open: (Ref. AMM TASK 71-13-00-010-040)
(2) FOR [1000EM1] (ENGINE-1)
437AL 438AR
(3) FOR [1000EM2] (ENGINE-2)
447AL 448AR
Subtask 71-13-15-110-052-B ** ON A/C NOT FOR ALL
A. Prepare the mating surfaces of the strake, the locator blade, the bonding strip, the back plate, the screws (15), the bolts (5), the washers (20), and the nuts (25 and 35) for the electrical bond.
(1) Use a scotch-brite type A CFS (Material No.CP2240) pad to remove all scratches and burrs which are more than 0.01 in. (0.25 mm) deep as follows:
(a) The surfaces of the bolts (5) where they will touch the bolt holes of the strake.
(b) The surfaces of the bolt holes of the strake where the bolts (5) will touch.
(c) The surfaces of the screws (15) where they will touch the holes of the locator blade.
(d) The surfaces of the holes in the locator blade where the screws (15) will touch.
(e) The mating surfaces of the washers (20).
(f) The mating surfaces of the nuts (25 and 35).
(g) The surface of the bonding strip 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).
(h) The surface of the back plate where the bonding strip will touch. Make an area smooth that is 0.25 in. (6,35 mm) larger than the surface of the bonding strip.
(i) The surface of the locator blade where the bonding strip will touch. Make an area smooth that is 0.25 in. (6,35 mm) larger than the surface of the bonding strip.
(3) Do an electrical bond resistance check.
(a) Put the strake, the back plate, and the bonding strip on the fan cowl.
(b) Install the bolts (5), the washers (30), and the nuts (35) at the two forward and two aft positions.
(c) TORQUE the nuts (35) to between 25 and 20 lbf.in (0.28 and 0.23 m.daN )
.
(d) Install the screws (15), the washers (20), and the nuts (25).
(e) TORQUE the nuts (25) to between 15 and 12 lbf.in (0.17 and 0.14 m.daN ).
(f) Put one lead of the OHMMETER MULTIRANGE on the head of a bolt (5) that goes through the bonding strip.
(g) Put the other lead of the OHMMETER MULTIRANGE on one of the screws (15) that goes through the locator blade.
(h) If the resistance is 1.0 ohm or more, remove the fasteners and clean the bond surface again. Do this procedure until the resistance is less than 1.0 ohm.
(i) Remove the nuts (25 and 35) , the washers (20 and 30), the screws (15), the bolts (5), the strake, the back plate, and the bonding strip from the fan cowl.
Subtask 71-13-15-420-051-B ** ON A/C NOT FOR ALL (1) Use a scotch-brite type A CFS (Material No.CP2240) pad to remove all scratches and burrs which are more than 0.01 in. (0.25 mm) deep as follows:
(a) The surfaces of the bolts (5) where they will touch the bolt holes of the strake.
(b) The surfaces of the bolt holes of the strake where the bolts (5) will touch.
(c) The surfaces of the screws (15) where they will touch the holes of the locator blade.
(d) The surfaces of the holes in the locator blade where the screws (15) will touch.
(e) The mating surfaces of the washers (20).
(f) The mating surfaces of the nuts (25 and 35).
(g) The surface of the bonding strip 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).
(h) The surface of the back plate where the bonding strip will touch. Make an area smooth that is 0.25 in. (6,35 mm) larger than the surface of the bonding strip.
(i) The surface of the locator blade where the bonding strip will touch. Make an area smooth that is 0.25 in. (6,35 mm) larger than the surface of the bonding strip.
WARNING:
BE CAREFUL WHEN YOU USE CONSUMABLE MATERIALS. OBEY THE MATERIAL MANUFACTURER'S INSTRUCTIONS AND YOUR LOCAL REGULATIONS.
(2) Clean all mating surfaces of the strake, the locator blade, the bonding strip, the back plate, and the bolts (5), 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 cloth before the solvent becomes dry. (3) Do an electrical bond resistance check.
(a) Put the strake, the back plate, and the bonding strip on the fan cowl.
(b) Install the bolts (5), the washers (30), and the nuts (35) at the two forward and two aft positions.
(c) TORQUE the nuts (35) to between 25 and 20 lbf.in (0.28 and 0.23 m.daN )
. (d) Install the screws (15), the washers (20), and the nuts (25).
(e) TORQUE the nuts (25) to between 15 and 12 lbf.in (0.17 and 0.14 m.daN )
. (f) Put one lead of the OHMMETER MULTIRANGE on the head of a bolt (5) that goes through the bonding strip.
(g) Put the other lead of the OHMMETER MULTIRANGE on one of the screws (15) that goes through the locator blade.
(h) If the resistance is 1.0 ohm or more, remove the fasteners and clean the bond surface again. Do this procedure until the resistance is less than 1.0 ohm.
(i) Remove the nuts (25 and 35) , the washers (20 and 30), the screws (15), the bolts (5), the strake, the back plate, and the bonding strip from the fan cowl.
B. Install the aerodynamic strake.
(2) Prepare the mating surfaces of the strake and the fan cowl for installation of the strake.
(a) Put the strake 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.
(c) Remove the strake.
(3) Put the strake, the back plate, and the bonding strip on the fan cowl.
(4) Install the bolts (5), the washers (30), and the nuts (35).
(5) TORQUE the nuts (35) to between 25 and 20 lbf.in (0.28 and 0.23 m.daN ).
(6) Install the screws (15), the washers (20), and the nuts (25).
(7) TORQUE the nuts (25) to between 15 and 12 lbf.in (0.17 and 0.14 m.daN ).
(8) Remove the masking tape 3M 202 (Material No.CP2185) from the fan cowl before the liquid shim cures.
(9) Remove unwanted liquid shim before it cures.
(10) Let the liquid shim cure. Refer to the manufacturers instructions.
Subtask 71-13-15-914-050-B ** ON A/C NOT FOR ALL NOTE: The procedure to install the aerodynamic strake on the left or 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 and the fan cowl for installation of the strake.
(a) Put the strake 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.
(c) Remove the strake.
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) to the surface of the strake 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 (Material No.CP2288) to the fan cowl inside the masking tape border. Refer to the manufacturers instructions. (3) Put the strake, the back plate, and the bonding strip on the fan cowl.
(4) Install the bolts (5), the washers (30), and the nuts (35).
(5) TORQUE the nuts (35) to between 25 and 20 lbf.in (0.28 and 0.23 m.daN )
. (6) Install the screws (15), the washers (20), and the nuts (25).
(7) TORQUE the nuts (25) to between 15 and 12 lbf.in (0.17 and 0.14 m.daN )
. (8) Remove the masking tape 3M 202 (Material No.CP2185) from the fan cowl before the liquid shim cures.
(9) Remove unwanted liquid shim before it cures.
(10) Let the liquid shim cure. Refer to the manufacturers instructions.
C. Apply the sealants.
(a) Apply sealant to the edges of the bonding strip where it touches the locator blade.
(b) Apply sealant to the heads of the screws (15) and to the nuts (25) that attach the bonding strip to the locator blade.
(c) Apply sealant around the nuts (25 and 35) and washers (20 and 30) that touch the bonding strip at the back plate.
(d) Apply sealant to the edges of the bonding strip where it touches the back plate. Push the sealant into the gap on the under side of the of the bonding strip.
(e) Let the sealant cure. Refer to the manufacturers instructions.
(4) ApplyCP 2497 silicone sealant DC93-006
CP 2244 primer 1200
CP 2497 silicone sealant DC93-006
(d) Let the sealant cure. Refer to the manufacturers instructions.
5. Close-upWARNING:
BE CAREFUL WHEN YOU USE CONSUMABLE MATERIALS. OBEY THE MATERIAL MANUFACTURER'S INSTRUCTIONS AND YOUR LOCAL REGULATIONS.
(1) Clean the heads of the screws (15), the nuts (25), the edges of the bonding strip where it touches the locator blade, the nuts (35), the locator blade, and the back plate with a clean, lint free cotton cloth and solvent. Make the surfaces dry with a clean, dry, lint free cloth before the solvent becomes dry. WARNING:
BE CAREFUL WHEN YOU USE CONSUMABLE MATERIALS. OBEY THE MATERIAL MANUFACTURER'S INSTRUCTIONS AND YOUR LOCAL REGULATIONS.
(2) Apply sealant: CAUTION:
DO NOT APPLY SEALANT BETWEEN THE BONDING SURFACES.
(3) Apply PR 1422A (Material No.CP2428) or PR1828 (faster cure alternate for PR1422A) to prevent moisture on (a) Apply sealant to the edges of the bonding strip where it touches the locator blade.
(b) Apply sealant to the heads of the screws (15) and to the nuts (25) that attach the bonding strip to the locator blade.
(c) Apply sealant around the nuts (25 and 35) and washers (20 and 30) that touch the bonding strip at the back plate.
(d) Apply sealant to the edges of the bonding strip where it touches the back plate. Push the sealant into the gap on the under side of the of the bonding strip.
(e) Let the sealant cure. Refer to the manufacturers instructions.
(4) Apply
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 the holes of the strake where you will apply the sealant 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.
(b) Apply WARNING:
BE CAREFUL WHEN YOU USE CONSUMABLE MATERIALS. OBEY THE MATERIAL MANUFACTURER'S INSTRUCTIONS AND YOUR LOCAL REGULATIONS.
(c) Apply (d) Let the sealant cure. Refer to the manufacturers instructions.
Subtask 71-13-15-410-051-B ** 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)
(3) FOR [1000EM1] (ENGINE-1)
437AL 438AR
(4) FOR [1000EM2] (ENGINE-2)
447AL 448AR
(5) Remove the access platform(s).
(6) Remove the WARNING NOTICE(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)
(3) FOR [1000EM1] (ENGINE-1)
437AL 438AR
(4) FOR [1000EM2] (ENGINE-2)
447AL 448AR
(5) Remove the access platform(s).
(6) Remove the WARNING NOTICE(S).