# SDR UIEA2024071800685

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: July 18, 2024
- Submitted: July 23, 2024
- Operation: Air carrier
- Aircraft: [N851GT](https://openairdocs.org/aircraft/N851GT), registered now
- Make and model: Boeing 747-87UF
- Registry model: [Boeing 747-87UF](https://openairdocs.org/model/boeing-747-87uf) (OpenAirDocs)
- Aircraft serial: 37565
- Aircraft time: 51,726 hours, 8,080 cycles
- System (JASC): [2133 · Pressure Regulator/Outflow Valve](https://openairdocs.org/jasc/2133)
- Part: Outflow Valve
- Part number: 50E991
- Part serial: 113
- Condition: Faulted
- Location: Cabin Pressure
- Stage of operation: CL
- How discovered: O
- Nature of condition: J
- Precautionary procedure: G, A
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/UIEA2024071800685

## Discrepancy

AIR TURN BACK UNABLE CRUISE ALTITUDE DUE TO PRESSURIZATION(<P>MIA MX PERFORMED INSPECTION OF EXTERIOR AND INTERIOR OF THE A/C, DOOR SEALS, A/C MANIFOLD DUCTING, NO ISSUES FOUND. R/R E/E FAN, R/R OVBD SOV, R/R X2 RELAYS FOR FWD CGO OVBD VALVE OPEN & CLOSE, & R/R FWD OVBD CGO VALVE</P>)

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