Weird looking prop spinner.

[fgayford]

As some of you may have noticed who get the Kitplane magazine, there is a strange (to me)looking spinner on the cover with Burt Rutan.
I think they said it was a pressure equalizing spinner or something like that.
Any one know what that is all about or what benefits one could expect from it?
Could Kess get another 5 mph with it?
Thanks
Fred

[blaswichk]

Naw, that's a 200mph spinner. I think that your looking at the one that's got a reverse flow, and is a point on the end. My freind had one on his Varieze.

kb

[earthstaraircraft]

In a message dated 5/31/2011 10:43:11 AM Pacific Daylight Time,
gayford@golden.net writes:

As some of you may have noticed who get the Kitplane magazine, there is a
strange (to me)looking spinner on the cover with Burt Rutan.
I think they said it was a pressure equalizing spinner or something like
that.
Any one know what that is all about or what benefits one could expect from
it?
Could Kess get another 5 mph with it?
Thanks
Fred




Hi Fred
The subject of pressure recovery is related to the interference of flows
that are converging at an angle that causes a collision if an after body,
like a spinner on a pusher, causes the flows to give up there convergence
energy, that would carry them in to a collision before they meet the opposing
flow, than the over all flow is smooth and harmonious. Its just like the
flair to a landing that we do all the time. Without the pressure recovery arc
each landing would be a crash.
Happy Flying
Mark

[fgayford]

Hi Mark
Is it like Kess said. Only good for high speeds?
Fred