# SDR 9712646740

- Type: Service difficulty report (as reported; unverified)
- 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](https://openairdocs.org/jasc/3610)
- 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
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/9712646740

## Discrepancy

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.

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