# SDR YENA2025072100736

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: July 18, 2025
- Submitted: July 21, 2025
- Operation: Air carrier
- Aircraft: [N4077J](https://openairdocs.org/aircraft/N4077J), 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: 11604
- Aircraft time: 6,363 hours, 984 cycles
- System (JASC): [4930 · APU Engine Fuel and Control](https://openairdocs.org/jasc/4930)
- Part: Fcu
- Part number: 707223652
- Part serial: CUC23603
- Condition: Failed
- Location: Zone 100
- Part time: 6,656 hours, 6,861 cycles
- Stage of operation: CR
- 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/YENA2025072100736

## Discrepancy

FLT#1333, BOS-SFO. (ETOPS) APU FAILED TO START IAW A49-00-01A. 3 START ATTEMPTS MADE OAT - 48 FL 360 ( APU SYSTEM A321NEO ETOPS ); REMOVED AND REPLACED APU FCU IRT AMM 49-32-11. OPS CHK SATISFACTORY. THIS CLEARS MDDR #588838. MCC NOTIFIED. MX-4 UPDATED. PLACARD REMOVED.

---
OpenAirDocs.org is an independent research project of [Contrail Labs](https://contraillabs.com/). It is not affiliated with the FAA or the NTSB. Source documents are U.S. government works in the public domain.