# SDR UIEA2026050500295

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: May 4, 2026
- Submitted: May 7, 2026
- Operation: Air carrier
- Aircraft: [N416MC](https://openairdocs.org/aircraft/N416MC), registered now
- Make and model: Boeing 747-47UF
- Registry model: [Boeing 747-47UF](https://openairdocs.org/model/boeing-747-47uf) (OpenAirDocs)
- Aircraft serial: 32838
- Aircraft time: 100,144 hours, 16,419 cycles
- Engine: Ge CF680C2B5F
- System (JASC): [7730 · Engine Ignition Analyzer System](https://openairdocs.org/jasc/7730)
- Part: Signal Cond Unit
- Part number: 6672M805
- Part serial: DE93
- Condition: Faulted
- Location: Nr 1 Engine
- Stage of operation: TO
- How discovered: O
- Nature of condition: R
- Precautionary procedure: C
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/UIEA2026050500295

## Discrepancy

HIGH SPEED RTO AT 140KTS INDICATED DUE TO ENG NR 1 NOT MAKING T/O THRUST.  R & R N1 FAN SHAFT SPEED SENSOR & ENG IDLE RUN CHKD OK IAW AMM 77-12-01/401, AMM 71-00-00/501 & IPC 77-12-01-01. NEED THE ENG HIGH PWR CHK.  R & R AVM SIGNAL CONDITIONER THEN OPS CHKD OK IAW AMM 77-31-03/401, AMM 71-00-00/501, IPC 77-31-03-01A.   VBV LINKAGE & LEAK VISUAL HMU LEAK CHKD NORMAL IAW AMM 72-36-00, AMM 75-32-00 & PERFORMED FIM 77-00-00-1 CONFIG 1, NO FAULT FOUND.  R & R ENG 1 FILTER & LEAK CHKD OK IAW AMM 73-11-03-404-014-J00 & IPC 73-11-03/401. ENG T/O PWR RUN AND ALL PARAMETERS NORMAL IAW AMM 71-00-00/501. PER MCC REQ, R & R NR 1 HMU, OPS CHKD NORMAL IAW AMM 73-21-14/401 & IPC 73-21-14-01.   ACCOMPLISHED NR 1 ENG POWER ASSURANCE CHK, ALL NORMAL IAW AMM 71-00-00/501.

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