SDR AALA20110126DFW05

Service difficulty report · Control Valve · Boeing 737823

Difficulty date: January 26, 2011
Submitted: January 27, 2011
Operation: Air carrier
Aircraft: N920AN
Make and model: Boeing 737823
Aircraft serial: 29521
Aircraft time: 34,097 hours, 13,944 cycles
System (JASC): 3610 · Pneumatic Distribution System
Part: Control Valve
Condition: Inoperative
Location: Bleed Air Sys
Stage of operation: TO
How discovered: O
Nature of condition: G
Precautionary procedure: B, A

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

What was found

DFW - CREW REPORTED LEFT BLEED TRIP OFF ILLUMINATED ON TAKEOFF. ACCOMPLISHED QRH AND LIGHT EXTINGUISHED. ACCOMPLISHED EMERGENCY DESCENT TO 10000 FT AND LEFT BLEED TRIPPED AGAIN. DURING DESCENT AIRCRAFT LOST PRESSURIZATION. FLIGHT RETURNED DFW LANDED WITHOUT INCIDENT. AIRCRAFT REMOVED FROM SERVICE. REPLACED LEFT ENGINE PNEUMATIC PRECOOLER CONTROL VALVE. SYSTEM GROUND CHECK NORMAL OPERATION.