# SDR CALA2026031014469

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: March 8, 2026
- Submitted: March 10, 2026
- Operation: Air carrier
- Aircraft: [N229UA](https://openairdocs.org/aircraft/N229UA), registered now
- Make and model: Boeing 777222
- Aircraft serial: 30557
- Aircraft time: 94,758 hours, 11,079 cycles
- System (JASC): [2611 · Smoke Detection](https://openairdocs.org/jasc/2611)
- Part: Smoke Detector
- Part number: PU90471WR1
- Condition: False Activation
- Location: Zone 900
- Stage of operation: CR
- 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/CALA2026031014469

## Discrepancy

THE TOMC CONTROLLER AND SENIOR MANAGER CONCUR THAT THE AIRCRAFT CAN BE RELEASED BACK TO SERVICE AFTER EXPERIENCING A DIVERSION OR AIR TURN BACK DUE TO A MECHANICAL REASON LOCKED BY SYSTEM. UNLOCKING TOMC GG AND SR MGR BK CONCUR ON FIX REF LP 8141323 REPLACED SMOKE DETECTOR AT LAV 4L ACCOMPLISHED GROUND TEST OPS CK GOOD NO FAULT FOUND.LAV DOOR 4L SMOKE DET SOUNDS INTERMITTLY PER DEBRIEF WITH FLIGHT CREW, 40 MINUTES INTO FLIGHT SMOKE DETECTOR WAS INTERMITTENT DURING FLIGHT. THEY STATED THAT IT TURNED OFF ON THE RETURN. UPON MAINTENANCE ARRIVAL TO AIRCRAFT, FOUND DECTECTOR INSTALLED TO BE FAULTY. REPLACED SMOKED DETECTOR ADD EMP:U123554 AT LAV 4L REF AMM TASKS 26-13-01-000-803 AND 26-13-01-400-802. PERFORMED ALL TEST ON CSCP REF TASK 26-13-00-710-801, NO FAULTS NOTED FOR LAV SMOKE DETECTOR. OKAY TO CONTINUE.

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