R ENG OVERSPEED
(Caution)

The Right Engine has automatically shut down due to an overspeed condition.

• N1 or N2 Rotor Speed is more than the permitted limits

Advisory Wire/Service Bulletin: None

Forum Articles/Infoservice/Newsletter: None

Rolls-Royce NTO 175 - Nuisance Cockpit Effects and Fault Messages

EICAS message set on-ground after a commanded engine shut-down / during engine run-down:

1. Access CAIMS Stored or Active faults. Select displayed message from menu below:
   - Select Fault Message -7326226RBR - R N1 SPEED CH A WRG/PROBE RNG7326227RBR - R N1 SPEED CH B WRG/PROBE RNG7326228RBR - R N2 SPEED CH A WRG/PROBE RNG7326229RBR - R N2 SPEED CH B WRG/PROBE RNG

   1. If none of these messages were set, continue with next step.

2. Get access to the engine exceedance profile maintenance pages and record the exceedance profile for N2 rotor speed as follows:

   1. The maximum speed of the N2 rotor.
   2. The quantity of time that the N2 speed was more than the limit.
   3. If the N2 overspeed was stable or not.
   4. Use the exceedance profile data below and the N2 overspeed limits graph to find out if the N2 overspeed was in Zone A or Zone B.

3. Get access to the engine exceedance profile maintenance pages and Record the exceedance profile for N1 rotor speed as follows:

   1. The maximum speed of the N1 rotor.
   2. The quantity of time that the N1 speed was more than the limit.
   3. If the N1 overspeed was stable or not.
   4. Use the exceedance profile data below and the N1 overspeed limits in forward thrust graph to find out if the N1 overspeed was in Zone A or Zone B.
   5. Use the exceedance profile data below and the N1 overspeed limits in reverse thrust graph to find out if the N1 overspeed was in Zone A or Zone B.

4. If N2 speed has either reached Zone A or Zone B, then perform steps 7 to 11.
5. If N1 rotor speed has either reached Zone A or Zone B in forward thrust, then perform following steps 12 to 15.
6. If N1 Overspeed has either reached Zone A or Zone B in Reverse Thrust, then perform steps 16.
   
   Troubleshooting N2 Overspeed Condition:
   
   
7. If the N2 overspeed is in Zone A, do the steps that follow:

   1. Examine the oil pressure filter element for metal or carbon contamination ((EMM79-21-02-220-801)). Make an analysis of an oil sample for acidity and free carbon content.
   2. Examine the magnetic chip-detectors for contamination
   3. Do the detailed inspection of the front-bearing-chamber magnetic chip-detector (AMM TASK 79-21-04-220-801).
   4. Do the detailed inspection of the rear-bearing-chamber magnetic chip-detector (AMM TASK 79-21-04-220-802).
   5. Do the detailed inspection of the accessory-gearbox magnetic chip-detector (AMM TASK 79-21-04-220-803).
   6. Turn the HP rotor in a counterclockwise direction (when you look from the front of the engine) ((EMM72-33-00-980-801)). If it does not turn freely or there are unusual noises, do not use force to turn the HP rotor. There is possibly internal damage.refer to your Rolls-Royce representative before to remove the power plant (AMM TASK 71-00-00-000-801) and Install a new power plant (AMM TASK 71-00-00-400-801).

8. Dry motor the engine (AMM TASK 71-00-00-866-804). If you hear unusual noises, refer to your Rolls-Royce representative before to remove the power plant (AMM TASK 71-00-00-000-801) and Install a new power plant (AMM TASK 71-00-00-400-801).
9. Examine the HP compressor ((EMM72-33-00-220-801)).
10. Examine the HP turbine blades (AMM TASK 72-40-00-220-802).
11. Do an engine ground run as follows:

    1. Start the engine (AMM TASK 71-00-00-866-806).
    2. Operate the engine to ground idle, and monitor the engine operation limits (AMM TASK 71-00-00-866-807).
    3. Stop the engine (AMM TASK 71-00-00-866-809).
    4. Monitor the engine run down time (AMM TASK 71-00-00-866-807).
    5. If the above checks and inspections are satisfactory, put the engine back to usual operation.
    6. If the above checks and inspections are not satisfactory, refer to your Rolls-Royce representative.
    7. If the N2 overspeed is in Zone B, refer to your Rolls-Royce representative before to remove the power plant (AMM TASK 71-00-00-000-801) and Install a new power plant (AMM TASK 71-00-00-400-801).
       
       Troubleshooting N1 Overspeed in fwd thrust:
       
       

12. If the N1 overspeed is in Zone A, do the steps that follow:

    1. Examine the LP compressor (fan) blades ((EMM72-31-02-210-801)).
    2. Examine the LP compressor outlet guide-vanes (AMM TASK 72-32-02-220-801).
    3. Visually examine the stage 2 LP turbine blades ((EMM72-50-00-220-801)).
    4. Examine the turbine section fairings for damage.
    5. Examine the oil pressure filter element for metal or carbon contamination ((EMM79-21-02-220-801)). Make an analysis of an oil sample for acidity and free carbon content.
    6. Do the detailed inspection of the front-bearing-chamber magnetic chip-detector (AMM TASK 79-21-04-220-801). Do the detailed inspection of the rear-bearing-chamber magnetic chip-detector (AMM TASK 79-21-04-220-802).
    7. Do the detailed inspection of the accessory-gearbox magnetic chip-detector (AMM TASK 79-21-04-220-803).
    8. Make sure that the LP rotor can turn freely in a counterclockwise direction (when you look from the front of the engine) without unusual noises. If it does not turn freely or there are unusual noises, do not use force to turn the LP rotor.refer to your Rolls-Royce representative before to remove the power plant (AMM TASK 71-00-00-000-801) and Install a new power plant (AMM TASK 71-00-00-400-801).

13. Dry motor the engine (AMM TASK 71-00-00-866-804). If you hear unusual noises, refer to your Rolls-Royce representative before to remove the power plant (AMM TASK 71-00-00-000-801) and Install a new power plant (AMM TASK 71-00-00-400-801).
14. Examine the LP turbine ((EMM72-50-00-220-801)).
15. Do an engine ground run as follows:

    1. Start the engine (AMM TASK 71-00-00-866-806).
    2. Operate the engine to ground idle, and monitor the engine operation limits (AMM TASK 71-00-00-866-807). Stop the engine (AMM TASK 71-00-00-866-809). Monitor the engine run down time of the LP system (AMM TASK 71-00-00-866-807). If the above checks and inspections are satisfactory, put the engine back to usual operation.
    3. If the above checks and inspections are not satisfactory, refer to your Rolls-Royce representative.
    4. If the N1 overspeed is in Zone B, refer to your Rolls-Royce representative before to remove the power plant (AMM TASK 71-00-00-000-801) and Install a new power plant (AMM TASK 71-00-00-400-801).
       
       Troubleshooting N1 Overspeed in Reverse thrust:
       
       

16. If the N1 overspeed is in Zone A, do the steps that follow:

    1. Do the fault isolation procedure for N1 speed is too high in forward thrust.
    2. Do a general visual inspection of the thrust reverser for damage and an overheat condition (AMM TASK 78-30-00-210-801).
    3. If the above checks and inspections are satisfactory, put the engine back to usual operation. If the above checks and inspections are not satisfactory, refer to your Rolls-Royce representative.
    4. If the N1 overspeed is in Zone B, refer to your Rolls-Royce representative before to remove the power plant (AMM TASK 71-00-00-000-801) and Install a new power plant (AMM TASK 71-00-00-400-801).

17. Do close out.