UFO- Useless Flying Object

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bmcj

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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.
I don't know, I kind of like the balloon tires. Also, they give some much needed shock absorption... Especially with the drop-in parachute-style landings I could see this design making at times.
 

FritzW

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Great way to protect the prop but these things land at a very high AoA, especially a short field landing. It looks like the rudder is going to hit way before the main gear.
 

cluttonfred

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The gear reminds me of the Sky Pup natural composite horizontal cantilever gear...a piece of maple cut to shape with tubular axles held on with U-bolts and a pair of bicycle nylon mag wheels. ;-)

wp611de452_06.jpg
 

litespeed

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Even better Sockmonkey,


Just need the gear to be shock absorbing and the wheel and spats thin.
 

Sockmonkey

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Disney movie!
A bit. I made it look a little cartoony on purpose to make it look user-friendly. That's also why it's a sunny yellow. The chunky look also gives the impression of durability, which I suppose is justified since all the structural members would be rather short in this configuration.
 

Sockmonkey

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It might be a case of perspective, but now it looks like it has insufficient wing area.
Zimmerman with a four meter span and three meter root chord.

Found a clip of that circular winged parachute plane flying.
[video=youtube;0OY85KJWXLY]https://www.youtube.com/watch?v=0OY85KJWXLY[/video]
 
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Thunderchook

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By the way it would be nice to know the span (or err diameter) of the UFO. Does anybody besides David Rowe know? (Or even better from David himself, if he were to privilege us goofballs with his presence.)
I have his phone number.
Does someone wanna put together a "shopping list" of information requests, and I can call him?
 

cluttonfred

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I think we would all like more details on specs and performance, and more drawings and/or photos, maybe just asking him for something like this? It would also be great to hear more about his design process/inspirations, the evolution of his various designs, and lessons learned.

SPECS
Length/span/area/height
Airfoil (including tweaks, twist, etc.)
Empty weight
Gross weight
Fuel capacity
Engine type
Prop diameter/pitch
Control system details (elevon mixer, etc.)

PERFORMANCE
Minimum (stall?) speed
Usual landing speed
Cruise speed
Maximum speed
Never-exceed speed
Rate of climb at X weight and Y speed under Z conditions

IMAGES
Drawings (3-view and/or detail drawings)
Photos (and all, especially without the covering)
 

lr27

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Some time ago, I ran a few rough numbers on a square (and I mean square) part 103 legal ultralight. Part of the reason for a square wing is that they allow simple calculations instead of an actual test of stall speed. Also to make fun of the rule. I planned to use a 4 stroke, 19hp vertical shaft lawnmower engine because it would be lighter than the horizontal shaft ones. There would be a large, belt driven, outward rotating prop on each front corner, kind of like on the Flying Flapjack (aka V-173) too. I imagine the long belts would be stretchy enough to get the oscillating frequency of the system below that of the engine at idle, and it would also allow a significant gear ratio for slow, large props. At least under power that ought to make a big difference in the induced drag. The horizontal stabs would be at the back of the square, sticking out. Kind of like the outboard horizontal stab configuration that is supposed to also reduce induced drag. The landing gear would have to be fairly tall. There would be a lot of transparent covering up front, for visibility.
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Barnaby Wainfan gave a lecture about the Facetmobile some years ago to TWITT. I imagine they still sell the tape. Barnaby's figure of merit for his aircraft is payload to drag, as opposed to L/D or something. The deep, small span fuselage means structural weight is kept minimal. He calculates that the L/D in cruise is better than that of a Cessna 152, while with similar power and the right size, it could carry another passenger at the same speed. More info at Facetmobile.com A report available on the web site suggests that such aircraft could be made cheaply out of flat panels. In the lecture, he suggests the 4 passenger version would have the volume of a Winnebago. At Oshkosh you could sleep inside it.

BTW, he said that, with the stick all the way back, the aircraft mushes down at about the rate of descent of a jet landing on an aircraft carrier. Not good for the plane, but a lot better than spinning in.
 

rotax618

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I posted a quick reply but it disappeared into the ether. Anyway I was simply commenting on the fact tha the UFO is only 12feet diameter, 113sq feet, David Rowe said that his proposed two seater would be 16feet diameter that would make it 201sq feet.
It can be seen from the videos that the induced drag doesnt detract from its climb performance considering it has only 50HP. These aircraft types have a higher power off sink, this can be an advantage in short field ops.
They are stable and can be built very light and strong because of the low parts count, short and deep spars.
Really an ideal simple sports airplane.
 

bmcj

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BTW, he said that, with the stick all the way back, the aircraft mushes down at about the rate of descent of a jet landing on an aircraft carrier. Not good for the plane, but a lot better than spinning in.
I'm sure that rate was measured in the air. I wonder how much cushioning effect you get when it enters into ground effect?
 

FritzW

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I really don't think you want a "free wing" on a Nemeth-type parasol, ...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.
Sorry to dig up a 3 month old post but the idea is still floating around in my otherwise empty head.

I was thinking more along the lines of a wing incidence handle (like an old Cessna flap handle). You could crank in 20 degrees of incidence on final. That way you could take advantage of the high AoA of the wing, still be able to see the runway and you wouldn't need super long gear legs.

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Why didn't airplanes like the Nemeth catch on? They seem to have real some advantages for the kind of flying I like to do (low, slow, off field).
 
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