DOC AIRBUS | TSM A320FN1 and N2 rotors locked together
TASK 72-00-00-810-814-A
N1 and N2 rotors locked together
2. Job Set-up Information
A. Referenced Information
3. Fault Confirmation
Subtask 72-00-00-710-068-A ** ON A/C NOT FOR ALL
Subtask 72-00-00-810-063-A ** ON A/C NOT FOR ALL
[Rev.8 from Aug 2018]
2026.04.04 04:35:10 UTC
N1 and N2 rotors locked together
NOTE: Interaction that you see between the high pressure turbine (HPT) rear rotating seal and low pressure turbine (LPT) forward rotating seal.
NOTE: Interaction is caused by tight clearances between the HPT and LPT rotating seal. When this occurs, it does not cause damage to the engine and is not a sign of hardware deterioration.
1. Possible Causes2. Job Set-up Information
A. Referenced Information
| REFERENCE | DESIGNATION |
|---|---|
| AMM 72-31-00-290-001 | Inspection of the High Pressure Compressor Rotor Assembly |
| AMM 72-31-00-290-002 | Inspection of the High Pressure Compressor Rotor Assembly |
| AMM 79-00-00-281-002 | Check of the Electrical Master Chip Detector (EMCD) for Particles |
| AMM 79-00-00-281-003 | Check of FWD Sump, AFT Sump, AGB, and TGB Scavenge Screens |
| AMM 79-21-10-210-002 | Check of the Lubrication Unit Magnetic Plugs and Scavenge Screens |
Subtask 72-00-00-710-068-A ** ON A/C NOT FOR ALL
A. During post/pre-flight inspection or maintenance, the engine N1 and N2 rotors will turn together with these conditions:
4. Fault Isolation- When the fan (N1) rotor or N2 rotor are turned manually, you hear a rattle of the accessory gearbox (AGB) gears.
- The locked rotors can occur on low or high time engines.
- It can correct itself by engine cool down.
- There were no abnormal engine faults reported by the flight crew during the previous flight such as high vibration or engine stall.
Subtask 72-00-00-810-063-A ** ON A/C NOT FOR ALL
A. EMCD and Scavenge Screens Inspection
(1) Do an EMCD and Scavenge Screens Inspection AMM 79-00-00-281-002 and AMM 79-00-00-281-003.
(a) If you find signs of engine damage, do the related maintenance steps.
(b) If no signs of engine damage are found, there is no specific maintenance action necessary.
(2) Turn the N2 Rotor AMM 72-31-00-290-002 to release the engine rotors.
Subtask 72-00-00-810-064-A ** ON A/C NOT FOR ALL (1) Do an EMCD and Scavenge Screens Inspection AMM 79-00-00-281-002 and AMM 79-00-00-281-003.
(a) If you find signs of engine damage, do the related maintenance steps.
(b) If no signs of engine damage are found, there is no specific maintenance action necessary.
(2) Turn the N2 Rotor AMM 72-31-00-290-002 to release the engine rotors.
B. Inspection of the Magnetic Plugs and Scavenge Screens
(1) Do an inspection of the magnetic plugs and scavenge screens AMM 79-21-10-210-002.
(a) If you find signs of engine damage, do the related maintenance steps.
(b) If no signs of engine damage are found, no specific maintenance action is necessary.
(2) Turn the N2 rotor AMM 72-31-00-290-001 to release the engine rotors.
(1) Do an inspection of the magnetic plugs and scavenge screens AMM 79-21-10-210-002.
(a) If you find signs of engine damage, do the related maintenance steps.
(b) If no signs of engine damage are found, no specific maintenance action is necessary.
(2) Turn the N2 rotor AMM 72-31-00-290-001 to release the engine rotors.