Corvair Onex Prop

Firewall Forward Propellers
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Still looking for a better prop for my Corvair 2850 powered Onex . Current Sensenich 54x58 has too much pitch. I would like to see another 250 rpm across the rpm range. I lengthened the landing gear and can use up to 60-61’ diameter.

Anyone have anything for sale?

Thanks,

Jeff

IMG_1914
IMG_19141920×1440 560 KB

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Hey Jeff,

I can’t help with a prop. Wish I could. But I just have to say: That is the coolest looking Onex I’ve ever seen.

I’m going to have to cut the sides of my cowl when I install EFI on the VW. I’ll have to add cheeks. I’ve done very little fiberglass work. If you could point me to a resource that would provide guidance on how you did that it would be greatly appreciated.

Wes

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Wes, a friend who runs his own composite shop lofted the teardrop shapes in CAD, then used a CNC table to make one-time use molds using pink foam. I then laid up 4 layers of bid into the molds, using 7725 style BID cloth and epoxy resin. Lots more work to then section the shapes with split lines/flanges at the firewall and upper/lower cowl split lines

Jeff

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I agree with Wes. That is awesome Jeff!

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Thanks Jeff,

I think I need a better class of friends :wink:

Wes

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I’ve got a buddy out in PA who has Waiex 181 with a Corvair on it. 54x54 Sensenich and he’s happy with it.

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Yowza! That is just an amazing Onex!!! I imagine it performs more like a rocket!

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I agree with the others … dat dar beez one fine lookin’ aeroplane fer sure!

Dale
3.0 Corvair/Taildragger

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Thanks for the nice comments!

Jeff

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Has anyone flown a Corvair powered Sonex with the Sensenich ground adjustable prop? Looks like they are 60-61” diameter. Considering this as an option, curious as to how it would perform on my plane (2850 OneX).

Jeff

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My understanding of the Corvair is they run higher RPM, like the AeroVee. That would make for a bad match with a large prop. The bigger diameter props make more sense in a Lycoming or Continental application where the RPMs are low. At 3400 RPM , a 54” prop will see a tip speed of about 800 fps. Speed of sound at sea level is a little over 1100 fps. With a 60” prop you are going to be approaching 900 fps.

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Would that be Billy?

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Tony

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Tony reports 135 kias at 3250 RPM, well below WOT.

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What is the engine speed at WOT?
AND
What is the prop tip speed at WOT?
:smiling_face_with_horns:

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I’m not sure he’s done a WOT run yet. IIRC max rpm for the Corvair is 3600. Prop diameter is 54”, or 137.16 cm, I’ll let you do the math so you get the units you like.

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848 FPS @ 3600 RPM
This would seem to be well within the speed of sound barrier 1,116 FPS however its likly that efficiency has significantly reduced and noise increased. :smiling_face_with_horns:

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Curious as to prop pitch and engine displacement.

Thanks,

Jeff

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2275, 105HP, 54x54 Sensenich.

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Thanks Bryan!

Jeff