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  #31  
Old 11-27-2011, 07:17 PM
aerhed aerhed is offline
 
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Location: Big Sandy, WY
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Quote:
so it acts in pitch, not yaw
That explains why I have to use up-rudder on takeoff.
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  #32  
Old 11-27-2011, 07:52 PM
WingsOnWheels WingsOnWheels is offline
 
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This looks like a great project. This is what experimental aviation is all about. I wish the builder the best of luck!
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  #33  
Old 11-27-2011, 07:57 PM
fehdxl fehdxl is offline
 
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Location: Bellevue, NE
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Originally Posted by johnny stick View Post
Jim,
I do not want to hijack thisd thread, but p-factor says the downward blade has more pitch therefore it produces more thrust on the one side, The OWT forgets this is a spinning propeller so it acts in pitch, not yaw. Helicopters and propellers share the same physics.
I understand what you're talking about...that is when one applies a force to a spinning object, the resultant movement is 90 degree later in rotation (spinning bicycle tire proves this well)...as does rapidly raising the tail in a conventional aircraft. However, helicopters rolling left because of retreating blade stall like descending propeller blades with more angle of attack (assuming positive aircraft pitch) providing more thrust than the rising propeller, does not follow that behavior. Still not convinced P-factor is an OWT.

And to keep it RV-6A reborn as a JAG-2 related...I sure hope all these aerodynamic forces stay in harmony for this project.

-Jim
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  #34  
Old 11-27-2011, 09:24 PM
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John Clark John Clark is offline
 
Join Date: May 2005
Location: Santa Barbara, CA
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Default A little History...

http://en.wikipedia.org/wiki/Wing_Derringer

John Clark ATP, CFI
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RV8 N18U "Sunshine"
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  #35  
Old 11-27-2011, 09:56 PM
SteinAir SteinAir is offline
 
Join Date: Feb 2005
Location: Minneapolis
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I'm with Peter....this just makes me go "hmmm"...I have sorta the same reaction to the Tripacer I saw with a T-Craft wing scabbed on the bottom of it a couple years ago - and yes, it still had it's top wing!

I guess I can't say too much without being sort of a hypocrite since I'm building something about the size of an RV with 500hp engine (that also hasn't been built for 50+ years) on the front!

Cheers,
Stein
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  #36  
Old 11-27-2011, 10:03 PM
Sig600 Sig600 is offline
 
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I've never heard my dad say ANYTHING good about his Corvair. Never heard anyone say anything good about a Corvair motor. Who would want to fly behind one? Let alone between TWO?!?
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  #37  
Old 11-27-2011, 10:16 PM
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Flyguytki Flyguytki is offline
 
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Location: Fairbanks AK
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Quote:
Originally Posted by SteinAir View Post
I'm with Peter....this just makes me go "hmmm"...I have sorta the same reaction to the Tripacer I saw with a T-Craft wing scabbed on the bottom of it a couple years ago - and yes, it still had it's top wing!

I guess I can't say too much without being sort of a hypocrite since I'm building something about the size of an RV with 500hp engine (that also hasn't been built for 50+ years) on the front!

Cheers,
Stein
Stein Please elaborate! 500HP and the size of an RV?

-david
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  #38  
Old 11-27-2011, 10:20 PM
johnny stick johnny stick is offline
 
Join Date: Dec 2008
Location: Los Angeles, CA
Posts: 301
Default p-factor last words I'll say

retreating blade stall causing a roll is also a OWT IMHO. I believe both these things are mis understood. There are other things that cause the right foot on climb out, the yaw when the tail is lifted, the reported roll with retreating blade stall (never experienced this in a heli either until I hit control limits), etc Everyone has their own ideas, I don't think I will change peoples minds, lets just leave it at that. By the way, it is only 90 degrees for helis. For a rigid attachment aka propellers, the precession force is more like 70 degrees, so there is some yaw, but a whole lot of pitch. The math is published in a book written by an old time Lockheed (Burbank) engineer.

Sorry to hijack this thread. Please start a new thread or PM me if anyone wants to discuss further.

Nice twin, I give him kudos for trying to do something different. I think we will all benefit from his experience and experimentation.
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  #39  
Old 11-27-2011, 10:29 PM
SteinAir SteinAir is offline
 
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Location: Minneapolis
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Quote:
Originally Posted by Flyguytki View Post
Stein Please elaborate! 500HP and the size of an RV?

-david
The MULLICOUPE

Though it usually doesn't garner the same reaction as a Twin Wing Tripacer or Twin Engine RV!

Cheers,
Stein
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  #40  
Old 11-27-2011, 10:50 PM
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rv6ejguy rv6ejguy is offline
 
Join Date: Mar 2005
Location: Calgary, Canada
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Quote:
Originally Posted by Sig600 View Post
I've never heard my dad say ANYTHING good about his Corvair. Never heard anyone say anything good about a Corvair motor. Who would want to fly behind one? Let alone between TWO?!?
I built many of these years ago for street and track. Actually a pretty robust design if you pay attention to detail and use a few modern parts. There are many flying now and with the 5th bearing installed to take the prop bending loads properly, they have been quite reliable.
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RV10 95% built- Sold 2016
http://www.sdsefi.com/aircraft.html
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