Flying wing as cheap and simple option for basic fun flying.

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Aesquire

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I'm with Hot Wings on the flat wrap idea. I'm not sure ANY flying wing will pass the OP's "not weird" requirement in the eyes of the public.

I do oppose any fancy weight shift mechanism, other than a sliding seat and the landing gear set so that a too-far-back cg tips the plane onto the tail bumper when the pilot sits down & straps in. ( The strap in part is important, no "I was leaning forward" surprises ) FAA specs call for the pilot to be able to overcome a runaway trim mechanism. Aft of range CG doesn't allow that. I can see that even the sliding seat can create a hazard if it can be moved in flight.
 

BBerson

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Milt's Little Bird, Facetmobile, Dyke Delta or other tractor types are superior to pushers that need very short moment arms from CG to controls. (for basic fun)
 

Jay Kempf

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Milt's Little Bird, Facetmobile, Dyke Delta or other tractor types are superior to pushers that need very short moment arms from CG to controls. (for basic fun)
Take the basic Facetmobile concept and put a tail on a steeeeeeek (Jose Jalapeno). A tiny bit more construction but still normal materials. Make normal tail dragger with retract mains in the wing. Then you have about the simplest plane possible. That takes the frantic short couple out of the equation. Think control line combat machine from way back. That would be one heck of a machine and the whole thing could be tooled in hot wired molds for skins or plywood negative ribs and aluminum sheet. Talk about easy to build.

Also I think you guys are missing that the Facetopel canopy WAS flat wrapped. You could need two molds for the fuselage halves or top and bottom. Easy stuff to CNC out. Make the pod big enough for guys and make some sort of movable ballast or battery.
 

Hot Wings

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2 problems with the Facetmobile:

Folding 'wings' for trailering is going to be an interesting engineering challenge

It's even further down the 'weird' scale than most flying wings. But it's so far down the mobius strip of weird it just might be marketable.
 

BBerson

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Take the basic Facetmobile concept and put a tail on a steeeeeeek (Jose Jalapeno). A tiny bit more construction but still normal materials. Make normal tail dragger with retract mains in the wing. Then you have about the simplest plane possible. That takes the frantic short couple out of the equation. Think control line combat machine from way back. That would be one heck of a machine and the whole thing could be tooled in hot wired molds for skins or plywood negative ribs and aluminum sheet. Talk about easy to build.

Also I think you guys are missing that the Facetopel canopy WAS flat wrapped. You could need two molds for the fuselage halves or top and bottom. Easy stuff to CNC out. Make the pod big enough for guys and make some sort of movable ballast or battery.
Yep, a wing with a stick to the tail was called "Fun Fly" R/C model from the 90’S.
I had a "Hog Wild" that was a thick wing with a very short fuselage to the tail. Symmetric airfoil and CG at 17% and reflexed full span ailerons, it was extremely stable. Essentially a flying wing with a small tail added for pitch and rudder.
 

FritzW

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"Not weird looking or intimidating to a pilot or non-pilot"

I'm interpreting that requirement as something that looks plausible, practical and safe, not scary. Something that looks (and is) cheap, quick and easy to build. ...Not something that looks like cover art for a Sci-Fi novel :gig:

Nothing that's been mentioned so far seems weird looking to me, non-conventional maybe, but not weird.
 

Norman

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I'm on board with 92.7% of your concept but how do envision forming the ribs?
With proper surface preparation aluminum can be bonded. Alumiprep 33 AKA "Bonderite" and Alodine seems to be the stuff to use. Also acrylate adhesives are used to assemble some aluminum vehicle bodies without a phosphorus etch. Styrofoam is adequate for the nose ribs of ultralights so let's not hear anymore nay-saying about tapered wings being too costly or time consuming. Just glue the blanks to the spar and hot-wire cut them in place with templates every 3 or 4 feet made from scrap you can find in the dumpster at any place that makes countertops. Fast, easy, cheap, and strong enough at 60 mph. Yeah the chemicals cost more than a box of rivets but the time savings could be huge.
 

rotax618

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The Arup - Hatfield Little Bird flying wings have greater CG range.
For a single seat Arup/ Little Wing a 14'- 15' span would give sufficient area, say a 7' centre section with 3.5'-4' folding tips which could be of hollowed out foam.
The planform has been shown to be stable over a fairwide CG range and with the pilot sitting close to the leading edge then visability is quite good for a tractor flying wing.
I saw the Facet Opal flying at Evans Head when the altitude record was broken. From my observation the pilot (Scott Winton) was extremely talented as the aircraft appeared to be marginally stable in pitch, reminding me of the control line combat models I flew when I was young.
I dont believe that a plank flying wing has sufficient pitch stability for the average everyday sport pilot, indeed some can be made to tumble both intentionally and unitentionally. You have to add chord to the wing, a canard or a tail.
 

cheapracer

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The Facet Opal does not look cheap or simple to me. It looks like a very high performance airplane, with retractable gear,
The retractable gear is a simple affair of a few over center levers, but so what, don't run retractable gear. if anything I am concerned about it's very narrow track just waiting for a wing tip and catch.


sad opal 9.jpgsad opal 8.jpgsad opal 7.jpgsad opal 6.jpg



a wet wing, .
Plastic fuel tanks, or whatever works.



round composite fuselage,.
Would be metal.



a molded canopy,
Flat wrap.



a fully "buried" engine, and a very tight cockpit not suitable for larger people.
Maybe a misunderstanding here, I proffer the Opal as the model to base a build from, not to replicate the Opal itself.



It's also twitchy to fly as far as I have read, probably like a full-on racer instead of a sport plane.
The instability is known about, as mentioned.


Here's a question about it, and reply by Norman (of HBA)...

Modifed NACA 66 13.5% (aprox) with reflex added - note the reflex was flat on top, not concave and the lower surface curve bought up to meet.

NACA 66(1)-212 airfoil
Max thickness 12% at 45% chord
Max camber 1.1% at 50% chord


There's your low speed problem. The NACA 6 digit series give up a big chunk of CLmax to get a long laminar flow. They are also pron to laminar separation bubbles at low speeds due to a sharp kink in the upper surface pressure gradient and the leading edge shape tends to cause an abrupt stall. Combine all those low speed flaws with a reflexed trailing edge and you have a wing that just can't slow down very well.
 

vtul

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If we're really talking Part 103, retractable gear, plus all that streamlining is going to probably exceed max speed with the usual UL engines, so in order to narrow down the design, is this really 103 intended?
 

erkki67

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Just my two cents, the Debreyer Pelican was or is a neat flying wing, only drawback are the tapered outer wing panels.

The same bird, built with shorter but square tips could make an interesting variant of it.
 

cluttonfred

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If you are going to go with square tips you may as well use a constant-chord wing, no sweep or twist, and make it a plank with elevons. If a tractor-engine design, pilot CG could be on the aircraft CG with a low-mounted wing so no need to adjust for pilot weight. The tractor engine would also allow you to use just one fin and rudder, and you could make the rudder removable for sideways trailering and storage or even put the fin and rudder both on a little boom and remove the whole thing when needed. An ultralight/microlight plank with a paramotor engine and no ambitions to soar, just a fun flyer, maybe using Sky Pup wood-foam-fabric construction, would be great fun.
 

vtul

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With a fully enclosed small fuselage, bubble canopy and a cantilevered double surfaced flying wing design, you've done wonders to reduce drag. Unfortunately, drag is important to UL re. the max speed requirement. Conventional ULs feature pilot in the breeze, struts and or wires, and a conventional fuselage and a separate tail. Lots of drag, and that fills in the slots on the 103 Appendix calcs for determining max speed.


And it essentially determines engine size, using that sheet. One solution to the requirements might be a smaller than usual engine. But If you have a very low drag design with a very small engine, climb performance will suffer unless you increase the wing's aspect ratio. So if the direction is 103 compliant we're probably talking a low powered high aspect ratio flying wing and/or one with "officially" draggy components.

And that starts to look like a Mitchell wing.
 

Hot Wings

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Nothing that's been mentioned so far seems weird looking to me, non-conventional maybe, but not weird.
your assessment of my meaning is pretty good. The Facetmobile is right on the line, IMHO, for non-aviation savvy individuals. That includes a lot of pilots... To me the Varhees and the Opal have very ungraceful ground motions. They look like small dogs trying to scratch what they can't reach on a carpet.:emb: That's the kind of 'weird' I'd like to avoid.

I dont believe that a plank flying wing has sufficient pitch stability for the average everyday sport pilot,.
That is a trait of a particular design, not the overall layout. Proper design to yield acceptable flight manners is to be presumed.


Plastic fuel tanks, or whatever works.



If we're really talking Part 103, retractable gear, plus all that streamlining is going to probably exceed max speed
Yes, clean part 103's generally have poor climb performance due to being Hp limited. There are ways around this....
But even though I like part 103 that shouldn't be a constraining parameter. Keeping it sport/LSA legal is probably good enough?
 
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vtul

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Yes, clean part 103's generally have poor climb performance due to being Hp limited. There are ways around this....
But even though I like part 103 that shouldn't be a constraining parameter. Keeping it sport legal is probably good enough?
Your call.
 

Norman

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Here's a question about it, and reply by Norman (of HBA)...

Modifed NACA 66 13.5% (aprox) with reflex added - note the reflex was flat on top, not concave and the lower surface curve bought up to meet.

NACA 66(1)-212 airfoil
Max thickness 12% at 45% chord
Max camber 1.1% at 50% chord


There's your low speed problem. The NACA 6 digit series give up a big chunk of CLmax to get a long laminar flow. They are also pron to laminar separation bubbles at low speeds due to a sharp kink in the upper surface pressure gradient and the leading edge shape tends to cause an abrupt stall. Combine all those low speed flaws with a reflexed trailing edge and you have a wing that just can't slow down very well.
I don't remember writing that exactly but it is true that the 6nxnnn airfoils have those problems and the higher the second digit is the worse the problem is. You can see both problems in XFLR5's OpPoint window. The leading edge problem shows up as a sharp pressure spike within a few %c of the leading edge and the bubble shows up as a little kink in the pressure distribution at the minimum pressure point. Both of these problems are fairly typical of highly laminar airfoil sections designed before the mid 1960s. We can do a lot better now. The airfoils that John Roncz designed for the Genesis are really quite good. Scaled to 18% it's almost as good as one of mine :ban::roll:
 

cheapracer

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Just my two cents, the Debreyer Pelican was or is a neat flying wing, only drawback are the tapered outer wing panels.

The same bird, built with shorter but square tips could make an interesting variant of it.
No.

The tapered tips put the ailerons closer to the CoG so it doesn't pitch as much when rolling. I learnt that from studying the Marske flying wing history, and that's why his have the taper at the CoG.

I am satisfied with my laser/rib flanges that now make tapered wings easy enough for me, albeit never as easy as straight wings of course.
 
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