Service difficulty report · Control Unit · Boeing 777222

Difficulty date
September 19, 2023
Submitted
September 21, 2023
Operation
Air carrier
Aircraft
N219UA
Make and model
Boeing 777222
Aircraft serial
30551
Aircraft time
85,403 hours, 10,639 cycles
Part
Control Unit
Part number
4885501002
Part serial
02380
Condition
Failed
Location
Spoiler Actuator
Part time
700,113 hours, 700,014 cycles
Stage of operation
DE
How discovered
O
Nature of condition
F, J
Precautionary procedure
B

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

What was found

SPOILERS EICAS ADVISORY FAILURE OF ONE OR MORE SPOILER PAIRS. FLT CONTROL SYS STATUS AFTER LANDING. REF MX MSG 27-10504, 27-10505, 27-10506 & 27-10510. PERFORMED SPOILER SYSTEM TEST PER AMM TASK 27-61-00-740-801 ALL TESTS PASSED. NO SPOILER MSG. DUE TO MSG 27-10510 OCCURRING ON INBOUND FLT LEG REPORT PERFORMED WIRING CHECK OF #11 SPOILER PCU PER FIM TASK 27-00-00-700-801 PARA. F TABLE 601. ALL READINGS WITHIN SERVICE LIMITS. VERIFIED INTEGRITY OF HARNESS FROM CONNECTOR DM27219 TO ACE L2 TO BE FREE OF SHORTS TO GROUND AND FROM PIN TO PIN PER WDM 27-61-13-2. NO FAULTS FOUND. ON ARRIVAL CORRELATED MAINT MSG 27-10510 AND 27-13055 LATCHED. REPLACED ACE L2 M27122 IAW AMM 27-02-02. PERFORMED ACE LRU INSTALLATION TEST - TEST FAILED. REF MX MSG 27-13006. PER FIM 27-02 TASK 884, SWAPPED ACE L1 AND L2. PER STEP B (A) 3). ACE IS BAD FROM STOCK. FAULT RE-VERIFIED WHEN ACE L1 AND L2 SWAPPED BACK TO ORIGINAL POSITIONS.