# SDR SWAA2012082707086

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: August 25, 2012
- Submitted: August 28, 2012
- Operation: Air carrier
- Aircraft: [N481WN](https://openairdocs.org/aircraft/N481WN), registered now
- Make and model: Boeing 737-7H4
- Registry model: [Boeing 737-7H4](https://openairdocs.org/model/boeing-737-7h4) (OpenAirDocs)
- Aircraft serial: 29853
- Aircraft time: 29,419 hours, 17,251 cycles
- Engine: Ge CFM567B24
- System (JASC): [7320 · Fuel Controlling System](https://openairdocs.org/jasc/7320)
- Part: Hmu
- Part number: 442369
- Part serial: BECW1401
- Condition: Faulty
- Location: Nr 1 Engine
- Stage of operation: CR
- How discovered: O
- Nature of condition: R
- Precautionary procedure: A
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/SWAA2012082707086

## Discrepancy

AIR TURNBACK/DECLARED EMERGENCY.  ENGINE THRUST BECAME UNCONTROLLABLE DURING FLIGHT SHORTLY AFTER LEVEL OFF.  THRUST DETERIORATED ON NR 2 THEN WENT NEAR MAX POWER, REDUCED TO IDLE.  NR 1 ENGINE DID THE SAME SHORTLY THERE AFTER.  REMOVED AND REPLACED NR 1 HMU PER MT.

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