# SDR UIEA2018031300390

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: March 8, 2018
- Submitted: March 13, 2018
- Operation: Air carrier
- Aircraft: [N407KZ](https://openairdocs.org/aircraft/N407KZ), registered now
- Make and model: Boeing 747-4KZF
- Registry model: [Boeing 747-4KZF](https://openairdocs.org/model/boeing-747-4kzf) (OpenAirDocs)
- Aircraft serial: 36134
- Aircraft time: 36,135 hours, 6,988 cycles
- System (JASC): [4910 · APU Cowling/Containment](https://openairdocs.org/jasc/4910)
- Part: Stiffener
- Condition: Cracked
- Location: Apu Firewall
- Stage of operation: IN
- How discovered: 9
- Nature of condition: O
- Precautionary procedure: K
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/UIEA2018031300390

## Discrepancy

APU FIREWALL FWD FACE AT BS 2658,  NR 2 STIFFENER  FOUND CRACKED.  THE FIREWALL STIFFENER WAS REPAIRED IAW RL-53-83-12510, REV A.

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