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This is interesting....

They have been around through other vendors for awhile. Sensenich makes a quality ground adjustable with preset pins. I love mine.
 
I think I may be missing the rational to have a ground adjustable prop. I see the only advantage is that you can dial in the right pitch for your particular airplane and preference. With all the RV info available, it is pretty easy to choose the right fixed pitch prop.
Maybe if you fly long cross countries and also spend some time flying in and out of short fields in the mountains you can adjust based on your mission for the day but even that seems a bit impractical to me. Are people with ground adjustable props regularly changing their pitch?
Can anyone straighten me out on advantages of a ground adjustable prop?
 
I bought the Sensenich GA prop on the last two RV’s I’ve had, which originally had the metal Sensenich fixed pitch. The problem was that even though they had the highest pitch that Sensenich sells, it wasn’t enough. They would both overspeed (well over 2700) the engine - as high as 3000 RPM at low altitude and wide open throttle. I didn’t want a prop shop to try to bend the metal prop to attain a good pitch. If you’ve ever seen how they do this, you would understand. My goal with my GA prop is to be able to use full power without overspeeding my O-360. I still get off the ground in about 350-450’ (640 msl, paved), have good climb rates, and get good cruise numbers. I can get 2700 RPM up to about 8-9000’. Max RPM drops off a little above 9000, but I’m seeing redline TAS in level flight at that altitude. I do have a relatively light RV6. I normally cruise at 65% power at those altitudes (245-2550 RPM, 20.5-21.5” MAP) and get around 170 KTAS, @ 7.8-8.0 gph.
 
plehrke said:
I think I may be missing the rational to have a ground adjustable prop. I see the only advantage is that you can dial in the right pitch for your particular airplane and preference. With all the RV info available, it is pretty easy to choose the right fixed pitch prop.
Maybe if you fly long cross countries and also spend some time flying in and out of short fields in the mountains you can adjust based on your mission for the day but even that seems a bit impractical to me. Are people with ground adjustable props regularly changing their pitch?
Can anyone straighten me out on advantages of a ground adjustable prop?
Click to expand...
I did the Colorado Pilots Association Mountain Flying Course which included flying to Leadville at 9950ft elevation and around 12k DA. Even Sensenich couldn’t really recommend a pin setting because they don’t test that high.

At 75% gross weight and that DA you had to adjust the prop to make the takeoff roll something manageable especially in some of the short strips we operated out of. One of the fields would have been impossible to make a takeoff before the end of the runway without a climb prop setting.

I also flew this plane from the east coast. I obviously didn’t want to fly such a cross country on a climb prop setting. This is the biggest advantage of a ground adjustable over fixed pitch.

When I left for home at 1700lbs in my RV-8A at 6000ft DA and my normal cross country cruise pitch setting the plane took 3000ft of runway to takeoff. DA is a huge factor in aircraft performance.

I gathered great data for my POH through using a tail mounted GoPro to count stripes on the runway and get my distances.
 
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