SDR UALA2009122103955

Service difficulty report · Control Unit · Boeing 757222

Difficulty date: December 20, 2009
Submitted: December 31, 2009
Operation: Air carrier
Aircraft: N501UA
Make and model: Boeing 757222
Aircraft serial: 24622
Aircraft time: 65,868 hours, 24,756 cycles
Engine: Pwa PW2037
System (JASC): 3610 · Pneumatic Distribution System
Part: Control Unit
Part number: 33990046U2
Part serial: 238
Condition: Malfunctioned
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

HIGH STAGE BLEED ILLUM, FLIGHT DIVERTED. FROM SNA WITH BLEEDS OFF DUE TO EXCESS FUEL, POSSIBLE TRIGGER OF BOTH FAULTS. FOUND LT & RT HIGH STAGE PILOT CONTROL OVER PRESSURE INDS POPPED. RESET LT HIGH STAGE PILOT CONTROL, REPLACED RT HIGH STAGE PILOT CONTROL. RAN BOTH ENGS, BLEEDS NORMAL, NO FAULTS.