# SDR UIEA2026092800920

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: September 29, 2026
- Submitted: September 29, 2026
- Operation: Air carrier
- Aircraft: [N498MC](https://openairdocs.org/aircraft/N498MC), registered now
- Make and model: Boeing 747-47UF
- Registry model: [Boeing 747-47UF](https://openairdocs.org/model/boeing-747-47uf) (OpenAirDocs)
- Aircraft serial: 29259
- Aircraft time: 109,107 hours, 17,581 cycles
- System (JASC): [2910 · Hydraulic System, Main](https://openairdocs.org/jasc/2910)
- Part: Hydraulic System
- Condition: Leaking
- Stage of operation: CL
- How discovered: O
- Nature of condition: K, J
- Precautionary procedure: A
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/UIEA2026092800920

## Discrepancy

RECEIVED REPORT OF HYD LEAK OBSERVED ON GROUND DURING TAXI/TAKEOFF. OBSERVED DROP IN HYD 1 QTY FROM 1.01 TO 0.88. ASSUMED ACTIVE LEAK AND RTB.  FOUND HYD LEAK AT LINE FITTINGS CONNECTED TO THE LH WING #1 HYD SUPPLY SHUT-OFF VALVE. HYD LINES TIGHTENED PROPERLY IAW AMM 27-13-01-404-009. PERFORMED HYD LEAK CHECK. NO LEAK FOUND, NO FURTHER DEFECTS NOTED.

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