UFO- Useless Flying Object

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revkev6

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i'm surprised no one has mentioned any of Snyders Arup designs?? the podiatrist who found that the shape of the felt heel lifts in a show seemed to glide well....


 
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StarJar

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Those are very helpful comments, StarJar. I wonder if you have messed around with any other low AR shapes in Xflr5? Square, delta, Zimmerman, D, etc?
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Matthew Long, Editor
Yes, but like I said, I wasn't smart enough to put the rudder inside the wing planform, thus my experimenting had shorter relative cords, which made it hard to get an adequate wing area.
But now, adding in what I learned from David Rowe's plane I think the attached drawing would give more vortex lift and a better l/d ratio.
The shape I drew in blue, has more vortex along the span,
(C and D compare vortex span).
Area B is to mainly get lift there instead of vortices. This can add a couple units to the L/d ratio.
But, you would have to be careful with the vortex drag, and not lift the nose to high without sufficient power, altitude and speed.
This all, is my amateur opinion, mainly again from Xflr5 in Vortex Lattice Mode.
 

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FritzW

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And some people find an aspect ratio of 1.0 to be too...high!
More footage of the "Flying Flounder" above (first 60 seconds of the video anyway). The landing and the takeoff really show how much AOA they can handle. ...and the complete lack of visibility at high AOA. To take advantage of what a very low AR wing can do, I think the pilot needs to be under the wing.

[video=youtube;i8y5suPs1uE]https://www.youtube.com/watch?v=i8y5suPs1uE[/video]
 
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rotax618

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Some years ago I asked David about plans, he said that he used a nail, a six foot length of string and a piece of chalk to draw the plans on the hangar floor, it is a twelve foot diameter circle. He also said that the CG was about 25% of the centreline chord.
 

cluttonfred

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Incidentally, this 12' diameter single-seater or even a larger 14' or 15' diameter two-seater could make a great "UPS plane," meaning a kit plane in which all the component parts are short enough to ship via ordinary parcel service, no freight service necessary. Maybe in fabric-covered aluminum tube and gusset with a few key part in premolded composites?
 

litespeed

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The solution to visibility is either sit under the wing or ..

Add some clear panels underneath and also take advantage of cheap and simple cameras with a screen. **** cheap and reliable these days. That could allow for a view in any direction in any part of the flight profile- which is good idea not matter the design.

And it keeps the cool looks.
 

FritzW

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What are the advantages/disadvantages of putting the engine on the LE vs. the nose of the fuselage?

I'm thinking a parasol with the disk mounted as a "free wing" might solve some of the high AOA issues on landing. ie. tilt the whole disk up about 20 degrees for landing.
 

Sockmonkey

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Me too! Except I'd go the "Nemeth Parasol" route.

View attachment 54964 View attachment 54965



Maybe recycle the One Tube Wonder idea and go for part 103

View attachment 54966 View attachment 54967

Disk is 12' x 14' with the axis moved 1' forward of the centerline. So ~132 sqft.
This lines up with something I was thinking about before. Essentially a gyrocopter with a disk wing on top instead of a rotor. Having the disk wing on a gimbal also makes it easy to design and experiment with since you can just copy a standard gyrocopter with minimal changes.
Simply connecting a pair of struts from near the wingtips to the stick lets you control pitch and roll. Heck, you could use a hang-glider type control bar.
 
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cluttonfred

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What are the advantages/disadvantages of putting the engine on the LE vs. the nose of the fuselage?

I'm thinking a parasol with the disk mounted as a "free wing" might solve some of the high AOA issues on landing. ie. tilt the whole disk up about 20 degrees for landing.
I really don't think you want a "free wing" on a Nemeth-type parasol, meaning the wing seeks it's own best angle of attack so you'd need the pitch control on the rear of the wing with perhaps a fixed horizontal stab to keep the fuselage aligned with the airflow. On the other hand, a variable-incidence wing with the pitch control still at the tail but the main wing incidence variable (though fixed at any given moment) might work well and would not be hard in a strut-braced parasol. Supermarine Dumbo meets Flying Flea meets Nemeth Umbrellaplane!

supermarine-type-522-s2437-dumbo-9900039.jpg flying_flea_2_148-38-640-480-80-wm-left_bottom-100-TakenattheAviationHeritageMuseumBullCreekWAAu.jpg Nemeth_Parasol_SM.jpg

I think the main reason to put the engine on the wing and not the nose would be to maximize slipstream effect, for example if you added a large slotted flap for low speed instead of relying on very high AOA vortex lift.
 
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Sockmonkey

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I'm kind of thinking in this direction.

Between the high wing, parachuting effect, big tires, and protected pusher prop you could land this thing darn near anywhere.
Only two-axis controls but the rudder and pendulum effect would give you a little proverse roll when yawing.
 

litespeed

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Keep going Sockmonkey,

That holds some promise- and just looks cool and efficient. Add some streamlined wheel pants and smaller wheels but thin ones. Make the pants a thin like on a solar racer and they can be directional stability as well.
 
M

Manticore

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I'm kind of thinking in this direction.

Between the high wing, parachuting effect, big tires, and protected pusher prop you could land this thing darn near anywhere.
Only two-axis controls but the rudder and pendulum effect would give you a little proverse roll when yawing.
That would go really nicely with the Art Deco styling I've been getting into lately.
I can just see this couple emerging from it:
images.duckduckgo.com.jpeg
Wouldn't work with modern lardasses though.
 
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