SDR 9712646740

Service difficulty report · High Stage Valve · Boeing 747251F

Difficulty date: June 28, 1997
Submitted: March 26, 2000
Operation: Air carrier
Aircraft: N640US
Make and model: Boeing 747251F
Aircraft serial: 23888
System (JASC): 3610 · Pneumatic Distribution System
Part: High Stage Valve
Part number: 7371091
Condition: Stuck
Location: Nr 4 Engine
Part time: 43,477 hours
Stage of operation: TO
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

DURING TAKEOFF, THE NR 4 ENIGNE EGT AND NACELLE TEMPERATURE INCREASED ABOVE NORMAL. AIRCRAFT COMPLETED TAKEOFF BUT DECLARED AN EMERGENCY, DUMPED FUEL AND RETURNED TO ANC. AIRCRAFT LANDED WITHOUT FURTHER INCIDENT. REPLACED THE PRE-COOLER, HIGH STAGE VALVE, AND HIGH STAGE CONTROLLER, OPERATIONAL CHECK GOOD.