The 'daydreamers' thread...post your craziest designs and concepts here

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Hephaestus

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lazybee4.png


Yeah ok it keeps getting more cub-ish not that it's a terrible thing. Yes the cowl holes are done tongue firmly in cheek. It made me laugh.

32cuft per wing - Rutan mold less seems out - 150lbs or so for the pair... Would like to keep it cantilevered however,
 

rotax618

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Very inspiring, perhaps the wing could be made up of three, say 7’6” sections with folding mechanism like the flying flea, to fit in a standard garage or shipping container.
 

rotax618

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Wing could be conventional 1/8” ply ribs with cap strips, hot wire cut foam intermediate D ribs, ply leading edge, moldless foam round tips (hollowed out). Say a box spar with Douglas Fir or Hemlock laminated top and bottom chord and diagonal marine ply shearweb.

Just dreaming.......
 

Hephaestus

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Pondering some form of folding, not sure about fitting in a seacan possibly workable.

Not sure on wood, thats usually not my preferred medium. Would be awesome if oratex 600 came in a translucent red or yellow!

The design does suit that vacuum bagged composite on glass table method (think nearly glass smooth outsides). Other than the wing - all the pieces look like they'd fit on a 4x8 table.

Edit, I'm trying to figure out where I'm going wrong with the roncz spreadsheets... It's showing 130kt cruise. That seems impossible... I need to sit back down with raymers on the Cd I think...
 
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Hephaestus

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And if built like a Skypup?
I've been long talking about tab in slot CNC cut XPS covered with carbon fiber... So kind of skypup, sgian dubh, or m19 squirrel like...

Done half ass well you get big glass smooth exterior finish, easy die crush model like assembly and self jigging. One basic technique for the whole structure...
 

Hephaestus

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lazybee-airfoil1.png
The fun of RC airfoils :) Green line is plotted Clark Y-(il) 12% @ 2.1deg.
Probably need to take a better look at the choice... Knew that was going to happen, just one of my least favorite tasks...
 

Hephaestus

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A one piece wing can swing 180° on a pivot. The Van's RV-5 does. So did the Backyard flyer.
Might fit into a 30/40' seacan that way, would have to lift the tail to clear overhead though.

Pretty sure they'd need to pivot back/down the 7' chord and under 6' height limits the options. Being a foot thick - dropping right outside the landing gear "V" style - results in a 9'8+ width so not so great for seacans or trailers.
 

bmcj

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Since we’re still talking short, fat wings, do all of you remember the Fike?
I remember seeing one around the airport when I was younger. Here are some photos and three views (not many photos available so I included some pics of models).

60BFBFE4-0DB1-4ADB-AB38-8D95226BA272.jpeg 78F2C956-DCBC-4E7E-8E6E-CA12929D4FDB.jpeg C9634B01-F969-4C8B-82FA-95DEBBBF59E3.jpeg 75B1C93E-96C5-44D7-9C39-69B9CD660C00.jpeg
 

Hephaestus

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Yeah, the aspect ratio 3:1 works well for RC models. I think AR-3 is the sweet spot for low AR.
Old NACA docs seem to agree there is some interesting aerodynamics in that AR:3 range.

But like the UFO Arup and others show there's something in the 1.27 range too...

Realized it's the LAA spreadsheet numbers I'm playing with (I've got a wierd amalgamation going, wanted them brought all onto one page) - pretty sure it's the elliptical Cdi that's resulting in the oddly high cruise speed. Probably need to leave the spreadsheet and do it by hand.
 

Hephaestus

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Tiger Tim

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I've never seen or heard of fike before, that's actually kind of neat. Off to google another rabbit hole.
Fikes are neat and have been pretty popular as free flight models where the rules constrained wingspan. IIRC the real deal has an overhead stick and a geodetic wing with a steel tube fuselage and tail. I think the idea was to have a good little airplane for getting around Alaska, the cantilever wing and top stick being there so you could get in and out easily in full cold weather gear.

Another low aspect plane to look up is the Lacey M-10. The Lacey looks kind of like a dumpy BD-4 but it also has a pivoting wing for easy storage.
 

BBerson

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But like the UFO Arup and others show there's something in the 1.27 range too...
Yes, a high CL at 1.27 AR. But it comes with high Cd. Not a concern to Zimmerman because he was designing for powered vertical lift.
We are concerned with Cd and the resulting L/D, from the combined CL and Cd.
 

bifft

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This is one of my crazier ones. Just a random sketch, started off as a double delta with a equilateral triangle at the front and then a 30 degree isosceles at the back. That looked to have too low of an aspect ratio, so I chopped off the outside half of the semispan and then stretched that out the distance of the original base of the triangle. Then cut the last 1/4 off that to not have pointy tips. Looked pretty neat. So I put it in to X-plane just to see what it would fly like.
triangle.jpg
Fooling with the controls and CG position I could make it fly. But not well. Flies pretty crappy actually. But it does look neat.
 

Speedboat100

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This is one of my crazier ones. Just a random sketch, started off as a double delta with a equilateral triangle at the front and then a 30 degree isosceles at the back. That looked to have too low of an aspect ratio, so I chopped off the outside half of the semispan and then stretched that out the distance of the original base of the triangle. Then cut the last 1/4 off that to not have pointy tips. Looked pretty neat. So I put it in to X-plane just to see what it would fly like.
View attachment 92095
Fooling with the controls and CG position I could make it fly. But not well. Flies pretty crappy actually. But it does look neat.
Looks like a raw sketch to me.

I intent to build this.
supa-wind (1).jpg
 
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