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Wanted: Christen Eagle ll Spades

patioed

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Looking for a set of Eagle II Spades...Good Condition, Good Price...
 

gmann750

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Give Benny Davis a call I think he still has a set or two.
 

PittsDriver68

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Raven Aircraft should be able to sell you some also.

If you wind up needing to fabricate your own, I have 3D CAD (Sketchup) drawings that I would share. The parts are pretty simple.

Best of luck,

Wes
 

Cameron

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I'd be interested in those CAD models if you don't care to share them Wes.
 

dxlyj

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Below are examples. Reverse engineered from the Aviat parts. PM me an e-mail address and I can send what I have.

Wes
The balance plates are triangular on 603TG. Arms look similar to what Wes posted.
--
Dave
 

patioed

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Good idea on Benny and Raven. I left a message for him today and will try Raven on Monday...
Wes, I think your CAD's are spot on to the spades on my recently sold
Eagle II..I'm seriously thinking about building a set...

Ed
 

PittsDriver68

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"balance plates are triangular"

The Pitts balance plates must have been what engineers call "a quick and dirty" solution. Low aspect ratio with high drag, low efficiency.

John Morrissey suggested to me that the Russians and French had access to wind tunnels to try out their spade designs and so did not choose simple rectangles.

Best of luck,

Wes
 

patioed

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Dave,
Can you post a picture of your spades when you have a chance...I have a feeling they are
very similar to Extra spades...
Ed
 

jerr888

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If you change the shape of the Pitts spades, you will have to use much heavier material. That angle on both sides is needed for stiffness !
Also, the area can be reduced if you have frieze type ailerons.
 

dxlyj

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Dave,
Can you post a picture of your spades when you have a chance...I have a feeling they are
very similar to Extra spades...
Ed
Will do. I'll be out there tomorrow and grab some rough dimensions too. I wasn't terribly fond of the feel when I first flew with them (I was transitioning from a Luscombe, which has leisurely ailerons), but they've started to grow on me.
--
Dave
 

cwilliamrose

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Dave,

Have you flown without them? I found the stock Eagle ailerons a little 'loose' in their feel -- the overall forces were more similar to an S-1S than an S-2A but they lacked the nice dense feel around neutral an S-1S has. I can't imagine putting spades on Eagle ailerons and ending up with something useful but I'm known for my love of spades (not).
 

dxlyj

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No Bill I haven't flown it without them yet. They're easy to remove but well, let's just say it's amazing how many things can conspire to interfere with flying ;-(
--
Dave
 

PittsDriver68

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Triangular spades - another application for carbon fiber and core. But please note that for a constant thickness applied to the airfoil shape from center to tip the Reynolds number and L/D curve changes along that axis. This complicates the calculation of lift, drag, and the resulting flight loads.

Steve Grohsmeyer made flat sheet higher aspect ratio spades for his Eigenhawk and ran into the flexing issue mentioned above. If you start down this road, some loads calculations backed up by sand bag testing is advised.

Rob Holland had an experimental spade disintigrate in flight. He described it to me as a very "interesting" experience. Best avoided. Caution advised doing development of this part of the flight control system...

Best of luck,

Wes
 
Last edited:

dxlyj

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Dave,
Can you post a picture of your spades when you have a chance...I have a feeling they are
very similar to Extra spades...
Ed
Here ya go. Sorry picture isn't better. Dimensions are 10" along the aft end, 8.25" on forward legs. I can mic thickness although I'm guessing in the .090" area.
--
Dave

LeftSpade.jpg
 

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