# SDR SWAA2026101481039

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: October 10, 2026
- Submitted: October 15, 2026
- Operation: Air carrier
- Aircraft: [N478WN](https://openairdocs.org/aircraft/N478WN), registered now
- Make and model: Boeing 737-7H4
- Registry model: [Boeing 737-7H4](https://openairdocs.org/model/boeing-737-7h4) (OpenAirDocs)
- Aircraft serial: 33989
- Aircraft time: 72,656 hours, 43,648 cycles
- Engine: Cfmint CFM567B242
- System (JASC): [7320 · Fuel Controlling System](https://openairdocs.org/jasc/7320)
- Part: Hmu
- Condition: Faulted
- Location: Nr 1 Engine
- Stage of operation: TO
- How discovered: O
- Nature of condition: R, J
- Precautionary procedure: C
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/SWAA2026101481039

## Discrepancy

AUTOTHROTTLE OVER-CONTROLS.  ON AUTOTHROTTLE ENGAGEMENT ON RUNWAY,  THRUST LEVERS WERE EVEN BUT NR 1 ENGINE REMAINED AT 40%, WHILE NR 2 ENGINE SPOOLED UP TO APPROX 70%,  A 30% SPLIT IN N1 INDICATION.   REJECTED TAKEOFF,  REMOVED & REPLACED NR 1 HMU IAW AMM 73-21-10. REMOVED AND REPLACED NR 1 EEC IAW AMM 73-21-60.

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