# SDR DALA2025091206742

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: September 8, 2025
- Submitted: September 12, 2025
- Operation: Air carrier
- Aircraft: [N521DN](https://openairdocs.org/aircraft/N521DN), registered now
- Make and model: Airbus A350-941
- Registry model: [Airbus A350-941](https://openairdocs.org/model/airbus-a350-941) (OpenAirDocs)
- Aircraft serial: 0661
- Aircraft time: 6,438 hours, 505 cycles
- System (JASC): [3620 · Pneumatic Indicating System](https://openairdocs.org/jasc/3620)
- Part: Warning Message
- Condition: False Activation
- Stage of operation: CL
- How discovered: O
- Nature of condition: N
- Precautionary procedure: A
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/DALA2025091206742

## Discrepancy

ATB- DUE TO (AIR L BLEED LEAK) MESSAGE.   PERFORMED HIGH POWER ENGINE RUN AND INSPECTED WING AND PYLON DUCTING WITH NO LEAKS FOUND. REPLACED BOMU (BLEED AND OVERHEAT MONITORING UNIT). (LP# 7575136, 7575137)

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