DOC AIRBUS | AMM A320FPower Assurance Test [PW11]
TASK 71-00-00-710-806-A
Power Assurance Test
Use this procedure to make sure that the engine will make rated TAKEOFF thrust within the EGT and N2 speed limits when you set power to an N1 target.
For more information about the power plant, refer to (71-00-00-00U).
2. Job Set-up Information
A. Fixtures, Tools, Test and Support Equipment
B. Work Zones and Access Panels
C. Referenced Information
3. Job Set-up
Subtask 71-00-00-941-139-A ** ON A/C NOT FOR ALL
(2) Let both engines become stable for five minutes at MINIMUM IDLE.
(3) If it is necessary (because of weather conditions described above) to operate the tested engine with the anti-icing system ON, you must operate the test engine as follows:
(a) On the ANTI-ICE section of panel 25VU, push the ANTI ICE/ENG 1(2) pushbutton switch (the ON legend of the ANTI ICE/ENG 1 (2) pushbutton switch comes ON).
(b) During the test, the anti-icing system must be OFF for the last 30 seconds (the engine operation must be stable) and then you must record the engine data:
1 Push the ANTI ICE/ENG 1(2) pushbutton switch (the ON legend of the ANTI ICE/ENG 1(2) pushbutton switch is OFF).
2 After you record the engine data, push the ANTI ICE/ENG 1(2) pushbutton switch (the ON legend of the ANTI ICE/ENG 1(2) pushbutton switch comes ON).
(4) Operate the tested engine with the engine BLEED OFF:
(a) The 60 percent power assurance table is calculated with the engine BLEED OFF.
(b) On AIR COND panel 30VU, make sure that the ENG 1(2) BLEED pushbutton switch is OFF (the OFF legend of the ENG 1(2) BLEED pushbutton switch is ON).
(5) Operate the tested engine with the GEN (VFG) loads OFF:
(a) The 60 percent power assurance table is calculated with the GEN (VFG) loads OFF.
(b) On ELEC panel 35VU:
1 Release the GEN 1(2) pushbutton switch (the OFF legend comes ON).
(6) Acceleration of the tested engine:
(7) Operate the engine at the percent N1 speed target value calculated previously from the 60 percent power assurance table for two minutes to let the engine become stable.
(8) After the test engine becomes stable, record the data that follows:
(10) Operate both engines for ten minutes at MIN IDLE to decrease the engine temperatures.
(11) Do the engine shutdown procedure for the both engines (Ref. AMM TASK 71-00-00-860-814).
Subtask 71-00-00-970-066-A ** ON A/C NOT FOR ALL
Subtask 71-00-00-860-228-A ** ON A/C NOT FOR ALL
[Rev.10 from 2021]
2026.04.01 12:57:10 UTC
Power Assurance Test
WARNING:
BE CAREFUL WHEN YOU USE CONSUMABLE MATERIALS. OBEY THE MATERIAL MANUFACTURER'S INSTRUCTIONS AND YOUR LOCAL REGULATIONS.
WARNING:
BE CAREFUL WHEN YOU DO WORK ON THE ENGINE AFTER SHUTDOWN. THE ENGINE CAN STAY HOT FOR A LONG TIME. IF YOU DO NOT OBEY THIS INSTRUCTION, INJURY CAN OCCUR.
ZONE: 400
1. Reason for the JobUse this procedure to make sure that the engine will make rated TAKEOFF thrust within the EGT and N2 speed limits when you set power to an N1 target.
For more information about the power plant, refer to (71-00-00-00U).
2. Job Set-up Information
A. Fixtures, Tools, Test and Support Equipment
| REFERENCE | QTY | DESIGNATION |
|---|---|---|
| 98F10103500000 | 2 | CHOCK-MLG,ENGINE RUN-UP |
| ZONE/ACCESS | ZONE DESCRIPTION |
|---|---|
| 400 | POWER PLANT, NACELLES AND PYLONS |
| 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 31-60-00-860-001-A | EIS Start Procedure |
| TASK 31-60-00-860-002-A | EIS Stop Procedure |
| TASK 71-00-00-860-814-A | Shutdown of the Engine |
| TASK 71-00-00-860-822-A | Start the Engine (Normal Manual Start) |
| TASK 71-00-00-860-823-A | Start the Engine (Normal Automatic Start) |
| TASK 71-00-00-910-803-A | Engine Operation Limits and Guidelines |
| TASK 71-00-00-910-804-A | General Warnings and Cautions and Related Safety Data |
| TASK 79-00-00-610-801-A | Check and Fill the Engine Oil |
Tool InstallationSubtask 71-00-00-941-139-A ** ON A/C NOT FOR ALL
A. Safety Precautions
(1) Review the operation limits and safety data to prepare the aircraft and engine for ground operation (Ref. AMM TASK 71-00-00-910-804) and (Ref. AMM TASK 71-00-00-910-803).
(2) Make sure that the aircraft is pointed into the wind for the power acceleration/deceleration test:
(a) Do a check and monitor for cross winds during the acceleration/deceleration test.
(b) Obey the wind direction and velocity operational limits (Ref. AMM TASK 71-00-00-910-803).
(4) If the aircraft begins to move while performing an engine run, immediately set all the thrust levers to the IDLE position.
Subtask 71-00-00-860-239-A ** ON A/C NOT FOR ALL (1) Review the operation limits and safety data to prepare the aircraft and engine for ground operation (Ref. AMM TASK 71-00-00-910-804) and (Ref. AMM TASK 71-00-00-910-803).
(2) Make sure that the aircraft is pointed into the wind for the power acceleration/deceleration test:
(a) Do a check and monitor for cross winds during the acceleration/deceleration test.
(b) Obey the wind direction and velocity operational limits (Ref. AMM TASK 71-00-00-910-803).
NOTE: This procedure can be performed at an ambient temperature range of -65 deg.F (-54 deg.C) to 127 deg.F (53 deg.C) and a test site altitude range of 0 ft. (0 m) - 10000 ft. (3048 m).
(3) 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. (4) If the aircraft begins to move while performing an engine run, immediately set all the thrust levers to the IDLE position.
B. Aircraft Maintenance Configuration
(2) Put in position the wheel 98F10103500000 CHOCK-MLG,ENGINE RUN-UP at each forward outboard MLG wheel.
(3) Energize the aircraft electrical circuits
(Ref. AMM TASK 24-41-00-861-002).
(4) Do the Electronic Instrument System (EIS) start procedure (Ref. AMM TASK 31-60-00-860-001).
(5) Make sure that the Integrated Drive Generator (IDG) and hydraulic pump loads are minimal for the engine test.
(6) Make sure the oil quantity is correct. Service the engine oil system if necessary (Ref. AMM TASK 79-00-00-610-801).
4. ProcedureCAUTION:
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) If necessary, remove the ice and the snow from the surface. (2) Put in position the wheel 98F10103500000 CHOCK-MLG,ENGINE RUN-UP at each forward outboard MLG wheel.
(3) Energize the aircraft electrical circuits
(Ref. AMM TASK 24-41-00-861-002).
(4) Do the Electronic Instrument System (EIS) start procedure (Ref. AMM TASK 31-60-00-860-001).
(5) Make sure that the Integrated Drive Generator (IDG) and hydraulic pump loads are minimal for the engine test.
(6) Make sure the oil quantity is correct. Service the engine oil system if necessary (Ref. AMM TASK 79-00-00-610-801).
CAUTION:
WIPE CLEAN ALL PARTS AND TOOLS AS NECESSARY TO REMOVE UNWANTED DEBRIS AND PREVENT DAMAGE TO THE ENGINE.
Subtask 71-00-00-860-227-A ** ON A/C NOT FOR ALL A. Aircraft Maintenance Configuration
(1) It is recommended that the wing and nacelle anti-ice switch is set to OFF for the test engine. The 60 percent power assurance table is calculated with the anti-icing system OFF:
(a) On the ANTI-ICE section of panel 25VU, make sure that the ANTI ICE/ENG 1(2) pushbutton switch is off (the ON legend of the ANTI ICE/ENG 1(2) pushbutton switch is off).
(2) It may be necessary to operate the engine with the anti-icing system on in the weather conditions that follow:
(a) There is moisture in the air that is rain or snow.
(b) There is moisture in the air so that you cannot see more than one mile (1.6 kilometers) because of fog.
Subtask 71-00-00-970-065-A ** ON A/C NOT FOR ALL (1) It is recommended that the wing and nacelle anti-ice switch is set to OFF for the test engine. The 60 percent power assurance table is calculated with the anti-icing system OFF:
(a) On the ANTI-ICE section of panel 25VU, make sure that the ANTI ICE/ENG 1(2) pushbutton switch is off (the ON legend of the ANTI ICE/ENG 1(2) pushbutton switch is off).
(2) It may be necessary to operate the engine with the anti-icing system on in the weather conditions that follow:
(a) There is moisture in the air that is rain or snow.
(b) There is moisture in the air so that you cannot see more than one mile (1.6 kilometers) because of fog.
B. Find and record the power assurance data and calculate the percent N1 target as follows.
(1) Get and record the airport pressure altitude at the location of the aircraft.
(2) Get and record the Total Air Temperature (TAT) as follows:
(a) Get and record the outside TAT value displayed on the ECAM (S/D PAGE).
(b) Record the TAT and refer to the performance table only when you are ready to start the test.
(3)
Subtask 71-00-00-710-246-A ** ON A/C NOT FOR ALL (1) Get and record the airport pressure altitude at the location of the aircraft.
(2) Get and record the Total Air Temperature (TAT) as follows:
(a) Get and record the outside TAT value displayed on the ECAM (S/D PAGE).
(b) Record the TAT and refer to the performance table only when you are ready to start the test.
(3)
NOTE: The 60 percent power assurance table in these figures are applicable from 0 ft. (0.00 m) to 10000 ft. (3047.94 m) altitude.
- Percent N1 speed target
- Percent N2 speed maximum target
- EGT C° maximum target
- Fuel flow (Wf) Kg/Hr maximum flow target.
CAUTION:
ALWAYS OPERATE THE ENGINE WITH THE ANTI-ICE SYSTEM ON WHEN YOU CAN SEE MOISTURE IN THE AIR AND THE AIR TEMPERATURE IS 5 DEGREES C (41 DEGREES F) OR LESS.
IN THESE CONDITIONS, IT IS POSSIBLE TO MAKE ICE IN THE ENGINE INTAKE AREA AND CAUSE DAMAGE IF THE ANTI-ICE SYSTEM IS OFF.
C. Power Assurance Test NOTE: It is necessary in this test that the engine on the opposite wing location be operated at the same time to give full hydraulic system redundancy.
The opposite wing engine is operated at IDLE.
(1) Start the engine to be tested and the opposite engine and set the power to IDLE in order to get full hydraulic system redundancy (Ref. AMM TASK 71-00-00-860-822) or (Ref. AMM TASK 71-00-00-860-823). The opposite wing engine is operated at IDLE.
(2) Let both engines become stable for five minutes at MINIMUM IDLE.
(3) If it is necessary (because of weather conditions described above) to operate the tested engine with the anti-icing system ON, you must operate the test engine as follows:
(a) On the ANTI-ICE section of panel 25VU, push the ANTI ICE/ENG 1(2) pushbutton switch (the ON legend of the ANTI ICE/ENG 1 (2) pushbutton switch comes ON).
(b) During the test, the anti-icing system must be OFF for the last 30 seconds (the engine operation must be stable) and then you must record the engine data:
1 Push the ANTI ICE/ENG 1(2) pushbutton switch (the ON legend of the ANTI ICE/ENG 1(2) pushbutton switch is OFF).
2 After you record the engine data, push the ANTI ICE/ENG 1(2) pushbutton switch (the ON legend of the ANTI ICE/ENG 1(2) pushbutton switch comes ON).
(4) Operate the tested engine with the engine BLEED OFF:
(a) The 60 percent power assurance table is calculated with the engine BLEED OFF.
(b) On AIR COND panel 30VU, make sure that the ENG 1(2) BLEED pushbutton switch is OFF (the OFF legend of the ENG 1(2) BLEED pushbutton switch is ON).
(5) Operate the tested engine with the GEN (VFG) loads OFF:
(a) The 60 percent power assurance table is calculated with the GEN (VFG) loads OFF.
(b) On ELEC panel 35VU:
1 Release the GEN 1(2) pushbutton switch (the OFF legend comes ON).
(6) Acceleration of the tested engine:
WARNING:
DO NOT OPERATE THE ENGINE WITH N1 AT MORE THAN 70% IN THIS TEST. IF YOU DO NOT OBEY THIS INSTRUCTION, THE AIRCRAFT CAN MOVE.
CAUTION:
IF THE ENGINE DOES A SURGE DURING THIS TEST, YOU MUST MOVE THE THRUST LEVER TO MIN IDLE AS QUICKLY AS POSSIBLE AFTER THE SURGE.
LET THE ENGINE BECOME STABLE AT MIN IDLE FOR FIVE MINUTES AND THEN CONTINUE THE TEST IF THE ENGINE DID NOT GO MORE THAN THE EGT LIMIT.
IF YOU DO NOT OBEY THESE INSTRUCTIONS, DAMAGE TO EQUIPMENT CAN OCCUR.
(a) Slowly accelerate the engine to the percent N1 speed target value calculated previously from the 60 percent power assurance table in Para. 4.B. (7) Operate the engine at the percent N1 speed target value calculated previously from the 60 percent power assurance table for two minutes to let the engine become stable.
(8) After the test engine becomes stable, record the data that follows:
- Record EGT (degrees C)
- Record percent N1 speed
- Record percent N2 speed
- Record fuel flow (Kg/Hr).
(10) Operate both engines for ten minutes at MIN IDLE to decrease the engine temperatures.
(11) Do the engine shutdown procedure for the both engines (Ref. AMM TASK 71-00-00-860-814).
D. (1) The tolerances in the 60 percent power assurance table allow for the differences that follow:
(3) For the fuel flow (Wf), you must subtract 45 Kg/Hr for each 1000 ft. (304.79 m) increase of altitude above sea level from the values shown in the 60 percent power assurance table.
(4) For the EGT, you must add 5.0 deg.C (41 deg.F) EGT for each 1000 ft. (304.79 m) increase of altitude above sea level to the values shown in the 60 percent power assurance table.
(5) If the recorded percent N1 at Para. 4.C.(8) is above the target percent N1 calculated at Para. 4.B, increase the limits (for N2, Wf and EGT) for every one percent N1 above the percent N1 target by the increments which follow:
(8) If the EGT or N2 speed are greater than the maximum values of the 60 percent power assurance table at the target N1 speed, the engine can be EGT or N2 limited at TAKEOFF power.
5. Close-up- The difference in performance between one engine and other engines.
- The difference in engine performance caused by initially worn engine parts (initial performance deterioration).
- The difference caused by humidity in the air.
(3) For the fuel flow (Wf), you must subtract 45 Kg/Hr for each 1000 ft. (304.79 m) increase of altitude above sea level from the values shown in the 60 percent power assurance table.
(4) For the EGT, you must add 5.0 deg.C (41 deg.F) EGT for each 1000 ft. (304.79 m) increase of altitude above sea level to the values shown in the 60 percent power assurance table.
(5) If the recorded percent N1 at Para. 4.C.(8) is above the target percent N1 calculated at Para. 4.B, increase the limits (for N2, Wf and EGT) for every one percent N1 above the percent N1 target by the increments which follow:
- 0.4 percent delta for N2
- 53 Kg/Hr delta for the fuel flow (Wf)
- 8.0 deg.C (46.4 deg.F) delta for the EGT.
- 0.4 percent delta for N2
- 53 Kg/Hr delta for the fuel flow (Wf)
- 8.0 deg.C (46.4 deg.F) delta for the EGT.
(8) If the EGT or N2 speed are greater than the maximum values of the 60 percent power assurance table at the target N1 speed, the engine can be EGT or N2 limited at TAKEOFF power.
Subtask 71-00-00-860-228-A ** ON A/C NOT FOR ALL
A. Put the aircraft back to its initial configuration.
(1) Make sure that the work area is clean and clear of tools and other items.
(2) Do the EIS stop procedure (Ref. AMM TASK 31-60-00-860-002).
(3) De-energize the aircraft electrical circuits
(Ref. AMM TASK 24-41-00-861-002).
(4) Remove the wheel 98F10103500000 CHOCK-MLG,ENGINE RUN-UP.
(1) Make sure that the work area is clean and clear of tools and other items.
(2) Do the EIS stop procedure (Ref. AMM TASK 31-60-00-860-002).
(3) De-energize the aircraft electrical circuits
(Ref. AMM TASK 24-41-00-861-002).
(4) Remove the wheel 98F10103500000 CHOCK-MLG,ENGINE RUN-UP.