Service difficulty report · Battery · Boeing 7878

Difficulty date
January 7, 2026
Submitted
January 9, 2026
Operation
Air carrier
Aircraft
N26906
Make and model
Boeing 7878
Aircraft serial
34829
Aircraft time
51,875 hours, 6,527 cycles
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

As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.

What was found

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.

More about the Boeing 787-8