# SDR CALA2026010812804

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: January 7, 2026
- Submitted: January 9, 2026
- Operation: Air carrier
- Aircraft: [N26906](https://openairdocs.org/aircraft/N26906), registered now
- Make and model: Boeing 787-8
- Registry model: [Boeing 787-8](https://openairdocs.org/model/boeing-787-8) (OpenAirDocs)
- Aircraft serial: 34829
- Aircraft time: 51,875 hours, 6,527 cycles
- System (JASC): [3350 · Emergency Lighting](https://openairdocs.org/jasc/3350)
- Part: Battery
- Part number: AD100260201
- Part serial: AD25032119
- Condition: No Test
- Location: Zone 200
- Part time: 522 hours, 57 cycles
- Stage of operation: IN
- How discovered: C
- Nature of condition: L
- Precautionary procedure: K
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/CALA2026010812804

## Discrepancy

WHILE OPS CHECKING FLOOR LIGHT AT 35F, FOUND ROWS. 33-38 AND ROWS 48-53 EMERGENCY LIGHTS INOPERATIVE. FOUND MAINT MESSAGE 33-11726 FOR WCU CLASS 26. AND MAINT MESSAGE 33-11729 FOR WCU CLASS 29 CONFIGURATION REPORT SHOWED FOR BOTH CLASS 26 AND 29 HAVING A FAILED LOAD. FOR CLASS 29, REPLACED WBU IAW AMM 33-51-07-02B-720A-A, OPS TEST OK. FOR CLASS 26.  REPLACED WCU REF AMM 33-51-07-01A-720A-A AND WBU REF AMM 33-51-07-02B-720A-A. OPS BATTERY,  TESTED OK.  ALL ASSOCIATED LIGHTS WITH WCUS ARE NOW OPERATIONAL. SYSTEM CONFIGURATION REPORT NO LONGER SHOWS ANY FAULTS FOR EITHER CLASS 26 OR 29. PERFORMED FULL GROUND TEST, GROUND TEST PASSED.

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