# SDR UIEA2014052100212

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: May 21, 2014
- Submitted: May 21, 2014
- Operation: Air carrier
- Aircraft: [N493MC](https://openairdocs.org/aircraft/N493MC), registered now
- Make and model: Boeing 747-47UF
- Registry model: [Boeing 747-47UF](https://openairdocs.org/model/boeing-747-47uf) (OpenAirDocs)
- Aircraft serial: 29254
- Aircraft time: 64,400 hours, 10,233 cycles
- System (JASC): [2120 · Air Distribution System](https://openairdocs.org/jasc/2120)
- Part: Duct
- Condition: Cracked
- Location: Ac Bay
- Stage of operation: CR
- How discovered: O
- Nature of condition: O
- Precautionary procedure: A
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/UIEA2014052100212

## Discrepancy

AIR TURN BACK, EXPERIENCED LOUD BANGING NOISE SHORTLY AFTER LEVELING OFF AT FL400.  INITIAL INSPECTION FOUND THE NR 1 PACK FWD & AFT RAM AIR DOORS DAMAGED.  FURTHER INSPECTION FOUND 2 CRACKS TO THE RAM AIR INLET DUCT MEASURING 0.375 INCH LONG.  TIME LIMITED REPAIR TO THE DUCT ACCOMPLISHED IAW SRM 51-10-02-0G-0.  EO 4421A096 PART 1 DOCUMENTS THE REPAIR.

---
OpenAirDocs.org is an independent research project of [Contrail Labs](https://contraillabs.com/). It is not affiliated with the FAA or the NTSB. Source documents are U.S. government works in the public domain.