DOC AIRBUS | AMM A320FAccel Check [CFMB]
TASK 71-00-00-710-025-A
Accel Check
This procedure gives instructions for single, fast accel from the 30 percent N1 setting. This will show that the engine accel operation is smooth and will not cause the engine to stall or flameout.
A. Fixtures, Tools, Test and Support Equipment
B. Referenced Information
3. Job Set-up
Subtask 71-00-00-869-206-A ** ON A/C NOT FOR ALL
Subtask 71-00-00-710-087-A ** ON A/C NOT FOR ALL
Subtask 71-00-00-869-110-A ** ON A/C NOT FOR ALL
[Rev.10 from 2021]
2026.04.01 12:55:17 UTC
Accel Check
CAUTION:
DO AN ON-WING TROUBLESHOOTING TEST TO CORRECT A PROBLEM BECAUSE A COMPRESSOR STALL HAS OCCURRED. IF YOU DO NOT DO THIS TROUBLESHOOTING AFTER A COMPRESSOR STALL, ENGINE DAMAGE MAY OCCUR.
1. Reason for the JobThis procedure gives instructions for single, fast accel from the 30 percent N1 setting. This will show that the engine accel operation is smooth and will not cause the engine to stall or flameout.
NOTE: Use this acceleration test procedure as an aid to do the troubleshooting of the engines on wing.
2. Job Set-up InformationA. Fixtures, Tools, Test and Support Equipment
| REFERENCE | QTY | DESIGNATION |
|---|---|---|
| No specific | AR | STOPWATCH |
| 98F10103500000 | 2 | CHOCK-MLG,ENGINE RUN-UP |
| REFERENCE | DESIGNATION |
|---|---|
| TASK 24-41-00-861-002-A | Energize the Aircraft Electrical Circuits from the External Power |
| TASK 24-41-00-861-002-A-01 | Energize the Aircraft Electrical Circuits from the APU |
| TASK 24-41-00-861-002-A-02 | Energize the Aircraft Electrical Circuits from Engine 1(2) |
| TASK 24-41-00-862-002-A | De-energize the Aircraft Electrical Circuits Supplied from the External Power |
| TASK 24-41-00-862-002-A-01 | De-energize the Aircraft Electrical Circuits Supplied from the APU |
| TASK 24-41-00-862-002-A-02 | De-energize the Aircraft Electrical Circuits Supplied from the Engine 1(2) |
| TASK 71-00-00-710-003-B | Engine Automatic Start |
| TASK 71-00-00-710-028-B | Engine Shutdown |
| TASK 71-00-00-869-003-A | Wind Limitations During Engine Ground Operations |
| TASK 71-00-00-869-004-A | Safety Precautions During Engine Ground Operations |
| TSM 71-00-00-810-807 | The Engine is Slow to Accelerate |
Tool InstallationSubtask 71-00-00-869-206-A ** ON A/C NOT FOR ALL
A. Safety Precautions
(2) Make sure that the 98F10103500000 CHOCK-MLG,ENGINE RUN-UP are in position in front of each forward outboard MLG wheel.
(3) Make sure that there is a minimum of 6614 lb (3000 kg) of fuel in the inner tanks to make sure that the aircraft is stable during the test.
(5) If the aircraft begins to move while performing an engine run, immediately set all the thrust levers to the idle position.
Subtask 71-00-00-861-065-A ** ON A/C NOT FOR ALL Subtask 71-00-00-865-101-A ** ON A/C NOT FOR ALL CAUTION:
MAKE SURE THAT THE AIRCRAFT IS PARKED ON A CLEAN, DRY AND FLAT SURFACE. THERE MUST BE NO OIL, GREASE OR SIMILAR MATERIALS ON THE SURFACE.
THE PAVEMENT MUST NOT BE BROKEN OR LOOSE, AND WE RECOMMEND CONCRETE MATERIAL BECAUSE ASPHALT CAN MELT AND CAUSE DAMAGE TO THE AIRCRAFT.
(1) Obey the wind limitations and safety precautions during engine ground operation (Ref. AMM TASK 71-00-00-869-003) and (Ref. AMM TASK 71-00-00-869-004). (2) Make sure that the 98F10103500000 CHOCK-MLG,ENGINE RUN-UP are in position in front of each forward outboard MLG wheel.
(3) Make sure that there is a minimum of 6614 lb (3000 kg) of fuel in the inner tanks to make sure that the aircraft is stable during the test.
NOTE: This minimum fuel quantity does not include the fuel consumption of the engines necessary to do the test. This minimum quantity must stay in the inner tank at the end of the test.
(4) There must be two qualified persons in the cockpit when performing an engine run. One must monitor the outside and the aircraft behavior while the other performs the engine test. (5) If the aircraft begins to move while performing an engine run, immediately set all the thrust levers to the idle position.
C. Make sure that this(these) circuit breaker(s) is(are) closed:
Subtask 71-00-00-869-108-A ** ON A/C NOT FOR ALL | PANEL | DESIGNATION | FIN | LOCATION |
|---|---|---|---|
| ** ON A/C NOT FOR ALL | |||
| 49VU | L/G/LGCIU/SYS1/NORM | 1GA | C09 |
| 121VU | HYDRAULIC/LGCIU/SYS2 | 2GA | Q35 |
| 121VU | HYDRAULIC/LGCIU/SYS1/GRND SPLY | 52GA | Q34 |
D. Measure and write down the Outside Air Temperature (OAT).
(1) On the AIR COND panel 30VU:
(5) Substract 5 percent N1 from the limit you noted, which gives the clock target point and record the new N1 percent.
Subtask 71-00-00-869-108-B ** ON A/C NOT FOR ALL NOTE: To measure the OAT, put a thermometer in the shade of the nose gear well.
NOTE: It is also possible to use the Total Air Temperature (TAT) indication from the ADC (shown on the ECAM system).
On the ADIRS CDU (overhead panel 20VU), set the three OFF/NAV/ATT selector switches to NAV. (1) On the AIR COND panel 30VU:
- Release the ENG 1(2) BLEED pushbutton switch (the OFF legend comes on).
- Release the GEN 1(2) pushbutton switch (the OFF legend comes on).
- Enter FLEX T/O temperature of 60 deg.C (140 deg.F) for OAT greater than or equal to 0 deg.C (32 deg.F).
- Enter FLEX T/O temperature of 40 deg.C (104 deg.F) for OAT less than 0 deg.C (32 deg.F).
| ACTION | RESULT |
|---|---|
| 1.On the MCDU, push the PERF MODE key | The TAKE OFF page comes on |
| 2.On the MCDU keyboard, enter the FLEX T/O temperature | The figures entered come into view at the bottom of the screen |
| 3.Push the line key adjacent to FLEX T/O TEMP | The entered value is memorized and shows in the FLEX T/O TEMP indication |
| 4.Move the throttle control lever of the tested engine to the FLEX MCT detent | The FLEX T/O N1 limit and FLEX T/O temperature show on the upper ECAM DU (upper right corner) |
| 5.Write down the N1 LIMIT shown on the ECAM | |
| 6.Move the throttle control lever of the tested engine to the IDLE position | The climb N1 limit comes on on the upper ECAM DU |
| 7.Push the MCDU MENU mode key | The MCDU MENU page comes into view |
D. Measure and write down the Outside Air Temperature (OAT).
(1) On the AIR COND panel 30VU:
(5) Substract 5 percent N1 from the limit you noted, which gives the clock target point and record the new N1 percent.
Subtask 71-00-00-710-086-A ** ON A/C NOT FOR ALL NOTE: To measure the OAT, put a thermometer in the shade of the nose gear well.
NOTE: It is also possible to use the Total Air Temperature (TAT) indication from the ADC (shown on the ECAM system).
On the ADIRS MSU panel 41VU, set the three OFF/NAV/ATT selector switches to NAV. (1) On the AIR COND panel 30VU:
- Release the ENG 1(2) BLEED pushbutton switch (the OFF legend comes on).
- Release the GEN 1(2) pushbutton switch (the OFF legend comes on).
- Enter FLEX T/O temperature of 60 deg.C (140 deg.F) for OAT greater than or equal to 0 deg.C (32 deg.F).
- Enter FLEX T/O temperature of 40 deg.C (104 deg.F) for OAT less than 0 deg.C (32 deg.F).
| ACTION | RESULT |
|---|---|
| 1.On the MCDU, push the PERF MODE key | The TAKE OFF page comes on |
| 2.On the MCDU keyboard, enter the FLEX T/O temperature | The figures entered come into view at the bottom of the screen |
| 3.Push the line key adjacent to FLEX T/O TEMP | The entered value is memorized and shows in the FLEX T/O TEMP indication |
| 4.Move the throttle control lever of the tested engine to the FLEX MCT detent | The FLEX T/O N1 limit and FLEX T/O temperature show on the upper ECAM DU (upper right corner) |
| 5.Write down the N1 LIMIT shown on the ECAM | |
| 6.Move the throttle control lever of the tested engine to the IDLE position | The climb N1 limit comes on on the upper ECAM DU |
| 7.Push the MCDU MENU mode key | The MCDU MENU page comes into view |
E. Start the two engines (Ref. AMM TASK 71-00-00-710-003) and let them become stable at minimum idle.
4. ProcedureSubtask 71-00-00-710-087-A ** ON A/C NOT FOR ALL
A. Do the accel check
(2) If the N1 target will be more than or equal to 75 percent, do this procedure:
(c) On the RUD TRIM/PARKING BRK panel 110VU:
- Set the PARKING BRAKE control switch to OFF.
(3) Set the opposite engine that you must not test to 60 percent N1.
(4) When the parameters become stable, move suddenly the throttle control lever from 30 percent N1 to the FLEX/MCT detent.
(6) Stop the chronometer when N1 reaches the FLEX T/O target minus 5 percent that you recorded in step 3.D.(5).
(7) Record the accel time in seconds. The guideline for this time equals 7.5 seconds.
(9) Put the aircraft in the "parking-brake applied" configuration:
(a) On the RUD TRIM PARKING BRK panel 110VU:
(10) Let the engines become stable for 3 minutes before shutdown.
(11) Stop the engines (Ref. AMM TASK 71-00-00-710-028).
Subtask 71-00-00-710-087-B ** ON A/C NOT FOR ALL WARNING:
DO NOT LET ONE ENGINE OPERATE AT N1 GREATER THAN OR EQUAL TO 75 PERCENT WHEN ONLY THE WHEEL CHOCKS AND THE PARKING BRAKE STOP THE MOVEMENT OF THE AIRCRAFT.
(1) Slowly push the throttle control lever of the engine you must test to 30 percent N1. Let the engine power become stable for a minimum of 3 minutes. (2) If the N1 target will be more than or equal to 75 percent, do this procedure:
CAUTION:
DO NOT OPEN LGCIU CIRCUIT BREAKERS 1GA, 2GA AND 52GA. IF YOU DO THIS, AIRCRAFT BRAKING THROUGH BRAKE PEDALS DOES NOT OPERATE.
(a) On the landing gear control and indicating panel 402VU: - Make sure that the A/SKID & N/WSTRG selector switch 5GG is ON.
- Make sure that the PARKING BRAKE control switch is in ON position.
(c) On the RUD TRIM/PARKING BRK panel 110VU:
- Set the PARKING BRAKE control switch to OFF.
(3) Set the opposite engine that you must not test to 60 percent N1.
(4) When the parameters become stable, move suddenly the throttle control lever from 30 percent N1 to the FLEX/MCT detent.
NOTE: During this action the following ECAM warning message can be shown : "CONFIG SLATS (FLAPS) NOT IN T.O CONFIG".
(5) Start the STOPWATCH at throttle control lever movement. (6) Stop the chronometer when N1 reaches the FLEX T/O target minus 5 percent that you recorded in step 3.D.(5).
(7) Record the accel time in seconds. The guideline for this time equals 7.5 seconds.
NOTE: If the time is higher than the guideline, make sure that:
- On the AIR COND panel 30VU, the OFF legend of the ENG 1(2) BLEED is on
- On the ELEC panel 35VU, the OFF legend of the GEN 1(2) is on.
NOTE: If you have these conditions, do the troubleshooting procedure related to a slow engine acceleration TSM 71-00-00-810-807.
(8) Move back the throttle control levers to the idle detent for the two engines. (9) Put the aircraft in the "parking-brake applied" configuration:
(a) On the RUD TRIM PARKING BRK panel 110VU:
- Set the parking brake control switch to ON.
(10) Let the engines become stable for 3 minutes before shutdown.
(11) Stop the engines (Ref. AMM TASK 71-00-00-710-028).
A. Do the accel check
(2) If the N1 target will be more than or equal to 75 percent, do this procedure:
(3) Set the opposite engine that you must not test to 60 percent N1.
(4) When the parameters become stable, move suddenly the throttle control lever from 30 percent N1 to the FLEX/MCT detent.
(6) Stop the chronometer when N1 reaches the FLEX T/O target minus 5 percent that you recorded in step 3.D.(5).
(7) Record the accel time in seconds. The guideline for this time equals 7.5 seconds.
(9) Release the brake pedals to put the aircraft in the "parking-brake applied" configuration.
(10) Let the engines become stable for 3 minutes before shutdown.
(11) Stop the engines (Ref. AMM TASK 71-00-00-710-028).
5. Close-upWARNING:
DO NOT LET ONE ENGINE OPERATE AT N1 GREATER THAN OR EQUAL TO 75 PERCENT WHEN ONLY THE WHEEL CHOCKS AND THE PARKING BRAKE STOP THE MOVEMENT OF THE AIRCRAFT.
(1) Slowly push the throttle control lever of the engine you must test to 30 percent N1. Let the engine power become stable for a minimum of 3 minutes. (2) If the N1 target will be more than or equal to 75 percent, do this procedure:
CAUTION:
DO NOT OPEN LGCIU CIRCUIT BREAKERS 1GA, 2GA AND 52GA. IF YOU DO THIS, AIRCRAFT BRAKING THROUGH BRAKE PEDALS DOES NOT OPERATE.
(a) On the landing gear control and indicating panel 402VU: - Make sure that the A/SKID & N/WSTRG selector switch 5GG is ON.
- Make sure that the PARKING BRAKE control switch is in ON position.
(3) Set the opposite engine that you must not test to 60 percent N1.
(4) When the parameters become stable, move suddenly the throttle control lever from 30 percent N1 to the FLEX/MCT detent.
NOTE: During this action the T.O CONFIG warning "CONFIG SLATS (FLAPS) NOT IN T.O CONFIG" can occur.
(5) Start the STOPWATCH at throttle control lever movement. (6) Stop the chronometer when N1 reaches the FLEX T/O target minus 5 percent that you recorded in step 3.D.(5).
(7) Record the accel time in seconds. The guideline for this time equals 7.5 seconds.
NOTE: If the time is higher than the guideline, make sure that:
- On the AIR COND panel 30VU, the OFF legend of the ENG 1(2) BLEED is on
- On the ELEC panel 35VU, the OFF legend of the GEN 1(2) is on.
NOTE: If you have these conditions, do the troubleshooting procedure related to a slow engine acceleration TSM 71-00-00-810-807.
(8) Move back the throttle control levers to the idle detent for the two engines. (9) Release the brake pedals to put the aircraft in the "parking-brake applied" configuration.
(10) Let the engines become stable for 3 minutes before shutdown.
(11) Stop the engines (Ref. AMM TASK 71-00-00-710-028).
Subtask 71-00-00-869-110-A ** ON A/C NOT FOR ALL
A. Close-up
(1) On the AIR COND panel 30VU:
(a) Push the ENG 1(2) BLEED pushbutton switch (the OFF legend goes off).
(2) On the ELEC panel 35VU:
(a) Push the GEN 1(2) pushbutton switch (the OFF legend goes off).
Subtask 71-00-00-862-065-A ** ON A/C NOT FOR ALL (1) On the AIR COND panel 30VU:
(a) Push the ENG 1(2) BLEED pushbutton switch (the OFF legend goes off).
(2) On the ELEC panel 35VU:
(a) Push the GEN 1(2) pushbutton switch (the OFF legend goes off).