Very low aspect ratio planes?

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delta

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I like that one a lot, but you are going to need a taller fin and rudder. I think you could also get away with simple triangular inverted-taper flaperons like so, which could help prevent tip stall at low speeds by washing out the outer sections of the wings. That has the makings of a fantastically quick and easy aluminum-tube-and-gusset, fabric-covered sport plane.

View attachment 109607
The rudder is 45" tall and 21" deep. Somebody else would have to do the math. I normally have elevons on my rc's and though cuffs have worked great for tip stall, I'm going to try tip fences just for drill. The flat plate design would also lend itself well to a foam and fiberglass/carbon construction, which is more what I have in mind at this time.ss15c.JPG
 

Urquiola

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Madrid, Spain
On the visibility questions with the Piana-Canova, I think it's important to remember that even his designs were not pure diamond shapes. One obvious modification would be to compress the area forward wing area and stretch the aft wing area to make a kite shape that follows the 25% chord of the airfoil allowing a straight main spar from wingtip to wingtip. I would also "snip off the points" on all four corners leaving what is in effect something very close to the Zimmerman planform but made with straight lines. Here is a pure diamond (blue) and the 25% chord kite shape (orange) overlaid on the PC.100:

View attachment 109577

Another approach to the visibility issue might be a pylon-mounted pusher engine behind the cockpit, allowing the cockpit to moved as far forward as possible for maximum visibility with clear leading edge sections if needed.
You for sure have the Langley Lippisch L-13/ DM-1 wind tunnelPlatillos alemanes 6Los hubo9 a.jpgPlatillos alemanes 6Los hubo9 b.jpg'La peonza'.gif study, but some may like having it here. The image of so called 'Spinning top' 'Peonza' looks rather a concrete building than a flying machine. German flying disc images look most counterfaited, the Schriever's machine is impossible to go airborne, according to experts. 'Urban Legends' Blessings +Discos nsdap9.jpgDiscos alemanes a.jpgDiscos alemanes b.jpg
 

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delta

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To many choices. Some work great at 1/4 scale, but time, money. inclination, and fortitude play a role in deciding to ride around in one.swr1.JPGswr2.JPGswr3.JPGswr4.JPGswr5.JPG
 

Sockmonkey

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To many choices. Some work great at 1/4 scale, but time, money. inclination, and fortitude play a role in deciding to ride around in one.
If you like, I could send you some of my sketchup files showing how I get it to handle airplane shapes properly.
 

Riggerrob

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If we’re going to get into fantasy flying saucers, I’ve always had a soft spot for this little hot rod
That was just one of the dozen or so flying saucers proposed by AVRO of Canada. They only built a two-seater, low altitude saucer and it barely got out of ground effect. Unfortunately it suffered such bad stability problems that the program was cancelled. Modern electronics might be able to stabliize it in the hover.
 

delta

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As far as I know, something like this has never been tried before. What am I missing besides the amphib gear?
lara1.JPGlara2.JPG
 

jedi

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Interesting idea. I expect it may morph into more of a Fleetwing Sea Bird (Fleetwings Sea Bird - Wikipedia).

Engine appears to be further forward than necessary which moves the pilot back for CG reasons. This reduces visibility for the pilot and makes CG control more difficult. The low wing would increase the vertical displacement between the thrust line and center of drag and mass so you may want to raise the wing a bit or even mount it to the engine pod. This would tend to make a mono hull with sponson more practical

You may even consider reverting to the biplane Grover Loening "Monoduck'" configuration, predisor to the Sea Bird. Then if the engine is too close to the cockpit or out front far enough to block visibility you might consider a pusher instilaton and end up with a copy of the Super Petrel LS, a very nice airplane with good handling and relatively low span which is a primary benefit of a low aspect ratio airplane.

Best of all it is a current production aircraft LS.

 

Sockmonkey

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Isn't having the engine at the front good for GC placement? You get to put the variable pilot and passenger weight close to the COL for easier trimming.
With a high prop on a short span delta body like that you can make it a monohull and ditch the floats since the central hull will be wide enough for stability.
 

Riggerrob

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Is a tractor prop any good on a low aspect ratio delta?
... Dyke Delta, Delta Kitten, Delta Stingray, Facetmobile, Piana-Canova, Verhees Delta, etc.

Is a high-mounted, tractor prop good on a seaplane?
Anderson Kingfisher, Dornier S-Ray, Fairchild, Fleetwings Seabird, and thousands of pontoon planes.
 

Sockmonkey

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Ooo, it would help the weight distribution if Detlta's seaplane used side-by side seating. Maybe slightly staggered for more elbow room.
 
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