On my RV-12 with a Rotax 912 ULS at full throttle my engine and/or propeller makes a pulsating harmonic sound. It’s particularly noticeable at full throttle while climbing, and less noticeable in cruise. It’s never just a constant level engine/propeller sound. I don’t notice any indication of it in the RPM or in performance.
If you have any ideas, propeller pitch, carb sync or anything else, please advise. The Carbs were sync'd with a Carb Mate and the two-bladed prop pitch is set per the construction drawings.
I fly out of Colorado at 7,600.' Horsepower and take-off/climb performance is obviously diminished, but it will easily make 5,500 RPM at cruise and 120 knots, as advertised. Regrettably, the pulsating harmonic sound is just "plane" annoying. I have about 130 hours on the airplane and it has done this since inception. Otherwise, it flys great!
Thank you for your time and any suggestions.
If you have any ideas, propeller pitch, carb sync or anything else, please advise. The Carbs were sync'd with a Carb Mate and the two-bladed prop pitch is set per the construction drawings.
I fly out of Colorado at 7,600.' Horsepower and take-off/climb performance is obviously diminished, but it will easily make 5,500 RPM at cruise and 120 knots, as advertised. Regrettably, the pulsating harmonic sound is just "plane" annoying. I have about 130 hours on the airplane and it has done this since inception. Otherwise, it flys great!
Thank you for your time and any suggestions.