# SDR HNAA2010110200237

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: October 20, 2010
- Submitted: November 2, 2010
- Operation: Air carrier
- Aircraft: N812EX
- Make and model: Dhav DHC8102
- Aircraft serial: 312
- Aircraft time: 46,255 hours, 50,935 cycles
- Engine: Pwa PW120
- System (JASC): [6120 · Propeller Controlling System](https://openairdocs.org/jasc/6120)
- Part: Switch
- Condition: Malfunctioned
- Location: Prop Torque
- Stage of operation: TO
- How discovered: O
- Nature of condition: J
- Precautionary procedure: O
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/HNAA2010110200237

## Discrepancy

PROP RPM AND TORQUE SURGE AFTER TAKEOFF. MX IN WEEK REPLACED POWER LEVER SWITCHS IAW ENGINE MANAGER.    CHECKED OPS OF BETA LOCKOUT SWITCH 6121-S4 DUE TO NR2 PROP RPM TORQUE SURGE.  FOUND SWITCH 6141-S4 INOP. R & R SWITCH IAW -8 MM 76-10-13. OPS CHECKED GOOD ON RUNUP IAW WORKCARD 61-21-10. ALSO RIGGED SWITCHES 2761-S2 AND 3261-S24, CKD GOOD ON RUNUP.

---
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.