# SDR SWAA114837

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: July 6, 2011
- Submitted: July 7, 2011
- Operation: Air carrier
- Aircraft: [N399WN](https://openairdocs.org/aircraft/N399WN), registered now
- Make and model: Boeing 737-3H4
- Registry model: [Boeing 737-3H4](https://openairdocs.org/model/boeing-737-3h4) (OpenAirDocs)
- Aircraft serial: 27693
- Aircraft time: 53,946 hours, 44,460 cycles
- System (JASC): [2410 · Alternator-Generator Drive](https://openairdocs.org/jasc/2410)
- Part: Csd
- Part number: 735511A
- Part serial: B3507
- Condition: Faulty
- Location: Nr 1 Engine
- Stage of operation: UK
- How discovered: O
- Nature of condition: O
- Precautionary procedure: D
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/SWAA114837

## Discrepancy

AIR TURNBACK - NR 1 BUS FALLS OFF THE LINE WHEN POWER IS ADVANCED BEYOND MID RANGE.  NR 1 BUS FALLS OFF WITH APU RUNNING.  REMOVED AND REPLACED NR 1 ENGINE CSD AND A/C GENERATOR PER MM.

---
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.