Service difficulty report · Pump · Boeing 747422

Difficulty date
February 26, 2003
Submitted
April 1, 2003
Operation
Air carrier
Aircraft
N199UA
Make and model
Boeing 747422
Aircraft serial
28717
Aircraft time
22,855 hours, 2,790 cycles
Engine
Pwa PW4056
Part
Pump
Part number
60721011
Part serial
123
Condition
Damaged
Location
Fuel Boost
Part time
7,154 hours, 784 cycles
Stage of operation
CL
How discovered
O
Nature of condition
J
Precautionary procedure
A

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

What was found

A/C RECEIVED RT-STAB FUEL PUMP EICAS INDICATION. RT HST TRANSFER PUMP FAILED TO OPERATE. THIS A/C WAS OPERATING UNDER THE CERTIFICATE LIMITATIONS OF AD 2002-24-52 AMOC LETTER 140S-02-384 DATED 12/6/02. THIS LIMITATION DID NOT ALLOW THE CREW TO SELECT THE LT TX PUMP ON WHEN THE RT PUMP FAILED. A FLIGHT MANUAL BULLETIN WAS ADOPTED TO ALLOW THE CREW TO SELECT THE LT PUMP ON IF THE RH PUMP FAILS. THE PUMP SENSE PORT THREADS WERE STRIPPED. IT IS UNLIKELY THAT THIS CAUSED THE EICAS MESSAGE WITHOUT CREATING A LARGE FUEL LEAK. IT PASSED THE BENCH CHECKS AND STATOR X-RAY INSPECTION.