Service difficulty report · Control Unit · Boeing 777222

Difficulty date
November 12, 2023
Submitted
November 16, 2023
Operation
Air carrier
Aircraft
N772UA
Make and model
Boeing 777222
Aircraft serial
26930
Aircraft time
100,691 hours, 18,726 cycles
Part
Control Unit
Part number
75860004
Part serial
0351
Condition
Faulty
Location
Sta 1790, E6 Rac
Part time
785,471 hours, 710,661 cycles
Stage of operation
TO
How discovered
O
Nature of condition
J, O
Precautionary procedure
C

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

What was found

MAIN GEAR STEERING EICAS INTERMITTANT GROUND RETURN, PILOTS REPORT NO HIGH ENERGY STOP. LOCKED OUT MLG APPLYING MEL 3253A. STEERING AND COMPLIED WITH MEL. REQUESTING 3253A. TOMC APPROVES THE USE OF MEL 3253A FOR MAIN GEAR STEERING SYSTEM INOP. PER FIM 32-53 TASK 801, TROUBLE SHOT TO A FAULTY MGSCU. REMOVED AND REPLACED MGSCU REF AMM 32-53-02. OPS CHECK GOOD PARTS USED: 27-3250-9-0001,QTY :1 ROTABLE PARTS CHANGE WAS INDICATED - TT # 1617185 SN OFF 0351 UNIT, CONTROL, OFF 27-3250-9-0001 0351 ON 27-3250-9-0001 0164.CREW REPORTS NO HIGH STOP. BREAKS NOT HOT. OKAY TO CONTINUE