# SDR UIEA2019080254842

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: July 29, 2019
- Submitted: August 2, 2019
- Operation: Air carrier
- Aircraft: [N446MC](https://openairdocs.org/aircraft/N446MC), registered now
- Make and model: Boeing 747-4B5F
- Registry model: [Boeing 747-4B5F](https://openairdocs.org/model/boeing-747-4b5f) (OpenAirDocs)
- Aircraft serial: 33517
- Aircraft time: 65,195 hours, 11,381 cycles
- System (JASC): [5414 · Nacelle/Pylon, Plate/Skin](https://openairdocs.org/jasc/5414)
- Part: Skin
- Condition: Corroded
- Location: Nr 4 Pylon
- Stage of operation: IN
- How discovered: V
- Nature of condition: O
- Precautionary procedure: K
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/UIEA2019080254842

## Discrepancy

AFTER REMOVED #4 PYLON FOUND SURFACE CORROSION ON I/B UNDER WING BOTH SIDE.(<P>#4 PYLON OUTBOARD PYLON I/B UNDER WING MID SPAR FTG SURFACE CORROSION SPOT FACE REPAIR AND BUSHING INSTALLED IAW SRM 57-20-90-2R-2 REPAIR 2. THIS REPAIR IS A CATEGORY B REPAIR.</P>)

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