# SDR UPS03240021

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: January 16, 2003
- Submitted: January 22, 2003
- Operation: Air carrier
- Aircraft: N937UP
- Make and model: Boeing 727-25C
- Registry model: [Boeing 727-25C](https://openairdocs.org/model/boeing-727-25c) (OpenAirDocs)
- Aircraft serial: 19302
- System (JASC): [2420 · AC Generation System](https://openairdocs.org/jasc/2420)
- Part: Relay
- Part number: BA10604501
- Condition: Inoperative
- Location: E/E Bay
- Stage of operation: TX
- How discovered: O
- Nature of condition: H
- Precautionary procedure: K
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/UPS03240021

## Discrepancy

DURING LANDING ROLLOUT & T/R APPLICATION A PWR LOSS TO THE FLT & ENGINE INSTRUMENTS WAS NOTED.  THE COCKPIT WENT MOMENTARILY DARK.  APPLIED T/R DURING TAXI IN AND NOTED KW NR 1 JUMPED TO 35 WHILE THE KWNR 2 DROPPED TO ZERO.  REMOVED AND REPLACED R58S POWER RELAY AND REPLACED R112 ESSENTIAL POWER RELAY.  REMOVED AND REPLACED LANDING GEAR ACCESSORY UNIT.

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