# SDR AALA202107122895

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: July 9, 2021
- Submitted: July 12, 2021
- Operation: Air carrier
- Aircraft: [N871AY](https://openairdocs.org/aircraft/N871AY), registered now
- Make and model: Boeing 787-8
- Registry model: [Boeing 787-8](https://openairdocs.org/model/boeing-787-8) (OpenAirDocs)
- Aircraft serial: 65991
- Aircraft time: 2,526 hours, 450 cycles
- System (JASC): [3350 · Emergency Lighting](https://openairdocs.org/jasc/3350)
- Part: Battery
- Condition: Inoperative
- Location: Emergency Lights
- Stage of operation: IN
- How discovered: V
- Nature of condition: O
- Precautionary procedure: K
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/AALA202107122895

## Discrepancy

AIRCRAFT WAS GROUNDED: MAINTENANCE MESSAGE 33-12131 FOR REMOTE WELS CONTROL UNIT. REMOVED AND REPLACED #31 WELS CONTROL UNIT (AALA202107120695) AND WELS BATTERY UNIT (AALA202107122895) IAW AMM 33-51-07

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