# SDR CA970422026

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: April 11, 1997
- Submitted: March 26, 2000
- Operation: Air carrier
- Make and model: Swrngn SA226TC
- Engine: Garrtt TPE33110UA
- System (JASC): [7797 · Engine Indicating System Wiring](https://openairdocs.org/jasc/7797)
- Part: Wire
- Condition: Shorted
- Location: Speed Switch
- Part time: 22,699 hours
- Stage of operation: CR
- How discovered: O
- Nature of condition: P
- Precautionary procedure: A
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/CA970422026

## Discrepancy

(CAN) CREW INTENTIONALLY SHUT DOWN LEFT ENGINE. ON ATTEMPTED START THE ENGINE WOULD UNFEATHER AND RPM WOULD INCREASE TO 15 PERCENT BUT FUEL FLOW AND IGNITION WERE NOT EVIDENT. LEFT SPEED SWITCH 10 PERCENT FUNCTION FOR IGNITION AND FUEL FLOW WAS SUSPECT. SWITCH REPLACED - NO GO. LEFT, 5 AMP CB REPLACED - NO GO. FURTHER INVESTIGATION FOUND THAT SOME REDUNDANT WIRING WAS SHORTING THE START CIRCUIT. THIS AIRCRAFT HAD BEEN ORIGINALLY CONFIGURED WITH AN OPTIONAL L/H SPEED SWITCH OVERRIDE. THE SWITCH HAD BEEN REMOVED BUT THE WIRING HAD BEEN LEFT IN THE AIRCRAFT. THESE WIRES HAD SHORTED.

---
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.