# SDR 2NSA100326727029

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: October 3, 2026
- Submitted: October 7, 2026
- Operation: Air carrier
- Aircraft: [N810MC](https://openairdocs.org/aircraft/N810MC), registered now
- Make and model: Agusta AW119MKII
- Registry model: [Agusta AW119MKII](https://openairdocs.org/model/agustawestland-philadelphia-aw119mkii) (OpenAirDocs)
- Aircraft serial: 15008
- Aircraft time: 256 hours
- Engine: Pwa PT6B37A
- Engine time: 223 hours, 773 cycles
- System (JASC): [7900 · Engine Oil System (Airframe Furnished)](https://openairdocs.org/jasc/7900)
- Part: Bypass Valve
- Part number: 727029
- Part serial: 897
- Condition: Failed
- Part time: 223 hours
- Component: Cooler Assy, Meggitt, 10862B
- Component part number: 109062087101
- Stage of operation: NR
- How discovered: O
- Nature of condition: M, J
- Precautionary procedure: A
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/2NSA100326727029

## Discrepancy

PILOT EXPERIENCED RISE IN ENGINE OIL TEMPERATURE DURING STRAIGHT AND LEVEL FLIGHT. PILOT COULD NOT RECTIFY THROUGH INITIAL EMERGENCY PROCEDURES AND INITIATED A LAND AS SOON AS POSSIBLE AND CONDUCTED PEL. OIL TEMP REACHED 116 DEG, FAULT TROUBLESHOT IAW PWC PT6B-37A 72.00.00 FIGURE 159, THERMOSTATIC BYPASS SUSPECTED AT FAULT DUE TO PREVIOUS FAILURES TO INCLUDE SIMILAR EVEN ON SDRS CONTROL # 202FA0000340. REPLACED PART THERMOSTATIC BYPASS VALVE, OPS CHECKS POST MAINTENANCE SAT.

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