Service difficulty report · Shaft · Boeing 777222

Difficulty date
May 8, 2008
Submitted
July 1, 2008
Operation
Air carrier
Aircraft
N787UA
Make and model
Boeing 777222
Aircraft serial
26939
Aircraft time
48,191 hours, 7,403 cycles
Engine
Pwa PW4090
Part
Shaft
Part number
1701768
Condition
Sheared
Location
Generator
Component
Generator
Component part number
1701768
Stage of operation
NR
How discovered
O
Nature of condition
W
Precautionary procedure
O

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

What was found

ELEC BACKUP GEN L LEFT BACKUP GENERATOR IS OFF OR HAS FAILED. ADVISORY MSG01- LATCHED CRUISE MODE DEPENDENT; BACKUP GENERATOR (L) OIL PRESSURE IS LOW. DB- BACKUP CONVERTER MSG02- ACTIVE CRUISE MODE DEPENDENT; BACKUP GENERATOR (L) HAS A SHEARED SHAFT. DB- BACKUP CONVERTER MSG03- NOT ACTIVE CRUISE MODE DEPENDENT; BACKUP GENERATOR (L) SPEED IS OUT OF RANGE. DB- BACKUP CONVERTER MSG04- NOT ACTIVE CRUISE MODE DEPENDENT; BACKUP GENERATOR (L) SPEED IS OUT OF RANGE. MSG-2446080 LATCHD ER MODE MSG-2446000 ACTIVE ER MODE MSG-2447000 INACTV ER MODE MSG-2447000 INACTV ER MODE. FOUND SHEARED SHAFT ON BACKUP GENERATOR. REPLACED NR 1 ENG BACK UP GENERATOR REF 24 -25-01. AC OK FOR SERVICE.