# SDR YENA2025091700943

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: September 16, 2025
- Submitted: September 17, 2025
- Operation: Air carrier
- Aircraft: [N4022J](https://openairdocs.org/aircraft/N4022J), registered now
- Make and model: Airbus A321-271NX
- Registry model: [Airbus A321-271NX](https://openairdocs.org/model/airbus-s-a-s-a321-271nx) (OpenAirDocs)
- Aircraft serial: 10303
- Aircraft time: 15,828 hours, 2,341 cycles
- System (JASC): [2421 · AC Generator-Alternator](https://openairdocs.org/jasc/2421)
- Part: Gcu
- Condition: Faulted
- Location: Nr 1
- Stage of operation: NR
- How discovered: O
- Nature of condition: J
- Precautionary procedure: O
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/YENA2025091700943

## Discrepancy

FLT#1621, LHR-BOS. (ETOPS) L-1 TSI ELEC GEN 1 FAULT-DUE TO ELEC GEN 1 FAULT ON PFR IN LHR & GCU1 SHOWING THE AT FAULT,  REMOVED AND REPLACED GCU NR 1 IAW AMM 24-22-34. OPS CHK GOOD. TSI CLOSED. GROUND VERIFICATION C/W PER AMM 24-22-34.

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