Concepts only: Doodles without numbers

[cluttonfred]

Kind of looks like Leonard Millholland (Legal Eagle) and Steve Wood (Sky Pup) got to brainstorming together.

 

[Riggerrob]

I really like the way yours looks. Put a pilot in it so we can see how it looks loaded. This pilot is 6' tall. I was kind of surprised that the model ended up with so much headroom (maybe I missed something). Usually my sketches are pretty tight.

The thing I drew would fit in a 16' space with the wings off. If it were set up for folding it would be too long.

The seat is pretty reclined on this concept. Since it's just a drawing I haven't set up incidence and gear height for optimal takeoff/landing. It looks "about right." But I haven't done the math.

If it looks a little short in the nose it's because I assume a heavier auto conversion. A lighter motor could be used. Just have to rework the nose/motor mount. Again all based on TLAR.

Rob

View attachment 121023

What is the total/flight configuration wing-span?

 

[Scottiniowa]

When you go from the standard (loosely said) Max type of wing of 54" cord (mini max, Hi-max, airbike, the eagles and many more) to your possibly proposed 48" cord, did you configure to lengthen the wing, to maintain lift?

 

[RJW]

The span is a little over 30' giving it about 120 square feet of area. I think this is a bit more than the Legal Eagle or the Minimax. The airfoil is a Riblett 30A615 that I modified slightly to make it easier to build.

Rob

 

[rtfm]

I really like the way yours looks. Put a pilot in it so we can see how it looks loaded. This pilot is 6' tall. I was kind of surprised that the model ended up with so much headroom (maybe I missed something). Usually my sketches are pretty tight.

The thing I drew would fit in a 16' space with the wings off. If it were set up for folding it would be too long.

The seat is pretty reclined on this concept. Since it's just a drawing I haven't set up incidence and gear height for optimal takeoff/landing. It looks "about right." But I haven't done the math.

If it looks a little short in the nose it's because I assume a heavier auto conversion. A lighter motor could be used. Just have to rework the nose/motor mount. Again all based on TLAR.

Rob

View attachment 121023

Isn't this just the Fritz design? Great looking pilot, though...

 

[RJW]

Well yeah, sort of. Except it's plastic and has a much higher aspect ratio wing. And to be honest I wasn't thinking about Fritz's design when I skeched it. I was more interested in Floyd's Cub design. I like Fritz's design. looks cool. Just dont like all the fiddly wood bits.

What's going on with the Fleabike? I've been following your build and like that you're a dancer too. Wish I had music. Any closer to finishing?

Rob

 

[cluttonfred]

Koen,

Going back to these sketches, I wonder if using elevons would make more sense, both because it would provide washout when needed to prevent top stall at low speeds and because I wonder about the effectiveness or responsiveness of spoilers.

I really like the idea of lightweight low AR sport aircraft as they have the potential for easy building and storage in tight spaces. A 1.0 m span center section with 4.0 m maximum chord and two 1.5 m span upward hinged tapered outer panels for 4.0 m total span would give you about 12-13 m2 (130-140 sq ft) of wing area. That’s more than enough for an ultralight single-seater or even a microlight two-seater and the whole thing could be easily built and stored in a single-car garage or 20’ ISO container.

I always loved Low Aspect Ratio designs. This was my thought about a easy storable light airplane. Rudder is easy to dismount. The rear part hinges up and folds over front and the total gets pushed sideways in a garagebox.
Airplane has a transparent front like some early Horten flying wings had.
View attachment 120134View attachment 120135View attachment 120136

 

[rtfm]

Well yeah, sort of. Except it's plastic and has a much higher aspect ratio wing. And to be honest I wasn't thinking about Fritz's design when I skeched it. I was more interested in Floyd's Cub design. I like Fritz's design. looks cool. Just dont like all the fiddly wood bits.

What's going on with the Fleabike? I've been following your build and like that you're a dancer too. Wish I had music. Any closerMrch - so we;re training every single day for a couple of hours.

The Fleabike is about to enter a period of quite rapid construction. For the past few months it has been a case of CAD and issues with the CNC. But the CNC should be back in action in a few days, and the CAD is (mostly) now complete. I hope to complete the rear wing and try out the folding mechanism. That is going to be fun.
As for dancing, we are competing in the Australian National Championships over the 4, 5 6 March. So we're training every single day for a couple of hours.

Duncan

 

[EzyBuildWing]

Russian Microlight..... about as minimal as you can get......!
( PS: If you dial "Cosworth single-cylinder 300cc 90 Hp at 20,000 rpm 4-stroke engine" into Youtube you'll see some interesting engines......

 

[Hannibal308]

Probably a stupid idea...wanted to cut the leading edge root back and blend into intakes for a TJ100 powered wing...

 

[Riggerrob]

Probably a stupid idea...wanted to cut the leading edge root back and blend into intakes for a TJ100 powered wing...
View attachment 121350

Yes.
That will create problems with span-wise airflow "turbulating" air flow into the engine intakes. At a minimum, you will need a small wing fence just outboard of the engine intakes.

 

[pylon500]

I like the idea of swept forward wings as much as swept back, although I find forward works out better from a pilot/structure layout point of view.
I'm also into metal;

Although I've looked into glass/foam sandwich composites;

I mean, most of these were pure dreaming, but ideas have to start somewhere.

So I was both a sailplane and hang glider pilot, and always wanted to mix the best of both;
One man portability.
Stand alone operation.
Reasonable performance.
Too old to go jumping off cliffs now, so I'll stick to ultralights, and maybe UL gliders.

 

[Hannibal308]

I like the idea of swept forward wings as much as swept back, although I find forward works out better from a pilot/structure layout point of view.
I'm also into metal;
View attachment 121354
Although I've looked into glass/foam sandwich composites;
View attachment 121355
I mean, most of these were pure dreaming, but ideas have to start somewhere.
View attachment 121357
So I was both a sailplane and hang glider pilot, and always wanted to mix the best of both;
One man portability.
Stand alone operation.
Reasonable performance.
Too old to go jumping off cliffs now, so I'll stick to ultralights, and maybe UL gliders.

Couple of your doodles look a lot like mine but much better! I love a true flying wing but as an F-16 guy I’d love to have that glider-like cockpit and visibility that a forward sweep can provide. I really don’t want a tail though…turns revolutionary into ordinary. Just dreaming.

 

[J.L. Frusha]

I really don’t want a tail though…turns revolutionary into ordinary. Just dreaming.

Turns instability into stability, afterall, it IS a Vertical Stabilizer...

 

[J.L. Frusha]

Latest iteration...

Twin Engine, strut-braced.

Guess I'll be making a foam-filled wooden box fuselage, not unlike the Hovey Whing Ding II and Pamperito

 

[Hannibal308]

Turns instability into stability, afterall, it IS a Vertical Stabilizer...

If there’s no instability in yaw, no need for a vertical stabilizer. Hence the importance of proverse yaw in a flying wing with a BSLD integral to its design.

 

[J.L. Frusha]

BSLD? Don't recognize the acronym...

 

[J.L. Frusha]

Adverse Yaw acts counter to the roll in a turn. The nose tends to swing out, away from the roll. As far as I know, there is no fixed-wing aircraft that doesn't experience adverse yaw.

 

[Hannibal308]

Adverse Yaw acts counter to the roll in a turn. The nose tends to swing out, away from the roll. As far as I know, there is no fixed-wing aircraft that doesn't experience adverse yaw.

Thank you.

A swept flying wing with a Bell Shaped Lift Distribution curve has the tips of the wings creating a small degree of down force during flight…just as the horizontal stabilizer does on your designs. When an aileron is deflected the downward force is reduced allowing the wing to rise. Induced drag is decreased and thus results in proverse yaw. The downward rolling wing, because the aileron (or elevon, in the case of many flying wings) is deflected to produce an increase in down force (lift downward) creates more induced drag which also acts as proverse yaw. No vertical stabilizer or rudder is necessary to maintain coordinated flight IF designed correctly.

By the way…your “Crotch ‘Stang” is so flippin’ cool!

 

[J.L. Frusha]

By the way…your “Crotch ‘Stang” is so flippin’ cool!

Thank you. I worked for over a month putting all of it into the right scale to look right and BE a flying crotch-rocket.

Think I'd have to wear a full rescue harness clipped to the thing, to insure buffeting doesn't toss me off of it.