# SDR UALA2010062302216

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: June 22, 2010
- Submitted: June 23, 2010
- Operation: Air carrier
- Aircraft: N559UA
- Make and model: Boeing 757222
- Aircraft serial: 26657
- Aircraft time: 59,468 hours, 21,931 cycles
- Engine: Pwa PW2040
- System (JASC): [4920 · APU Core Engine](https://openairdocs.org/jasc/4920)
- Part: B-Nut
- Condition: Loose
- Location: Shuttle Valve
- 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/UALA2010062302216

## Discrepancy

APU 3 START ATTEMPTS WITH APU FAULT EACH TIME.  99 PERCENT OF FAILED STARTS OCCUR IN DEN USUALLY OK NEXT STA CHECK ALL THE MUSCLE LINES FOR LEAKS & SECURENESS  & OF SHUTTLE VALVE INDX 116.   FOUND B NUT LOOSE ON SHUTTLE VALVE LINE, SECURED NUT. OPS CHECKED SEVERAL TIMES. APU STARTED AND RAN STRONG.

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