# SDR 9626706739

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: December 20, 1996
- Submitted: March 26, 2000
- Operation: Air carrier
- Aircraft: N639US
- Make and model: Boeing 747251F
- Aircraft serial: 23887
- System (JASC): [2910 · Hydraulic System, Main](https://openairdocs.org/jasc/2910)
- Part: Pressure Tube
- Condition: Leaking
- Location: Nr 1 Hyd Sys
- Stage of operation: CL
- Nature of condition: K, J
- Precautionary procedure: A
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/9626706739

## Discrepancy

DURING CLIMB, THE HYDRAULIC FLUID IN THE NR 1 HYDRAULIC SYSTEM DECREASED.  AIRCRAFT RETURNED TO NRT AND LANDED WITHOUT INCIDENT.  REPLACED THE PRESSURE TUBE ON THE PRESSURE MODULE.  OPERATIONAL CHECK GOOD.

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