# SDR WRLA990

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: April 9, 1999
- Submitted: March 26, 2000
- Operation: Air carrier
- Aircraft: N272WA
- Make and model: Doug MD-11
- Registry model: [Doug MD-11](https://openairdocs.org/model/mcdonnell-douglas-md-11) (OpenAirDocs)
- Aircraft serial: 48437
- System (JASC): [2450 · AC Power Distribution System](https://openairdocs.org/jasc/2450)
- Part: Relay
- Part number: 763222
- Condition: Failed
- Location: Nr 2 Bus
- Stage of operation: UK
- Nature of condition: H
- Precautionary procedure: A
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/WRLA990

## Discrepancy

NR 2 BUS TIE RELAY FAILED CAUSING LOSS OF NR 2 GENERATOR BUS DURING FLIGHT RESULTING IN AN AIR TURNBACK TO WMKK.  MAINTENANCE REMOVED AND REPLACED NR 2 BUS TIE RELAY AND THE ELECTRICAL POWER CONTROL UNIT.  OPERATIONAL CHECKS OF THE SYSTEM CHECKED OK.  (M)

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