ProBroJoe

Hey all,

I seem to remember a discussion here a while back about flying wings and their simplicity. I also got the impression that one could take a wing from a traditional aircraft and with a little hacking / gluing build a decent flying wing from one.

For example; John Doe crashes an airplane with a constant chord wing, destroys fuselage and one half of the wing. Would it be possible to saw off the bad portion (and any dihedral) and build a decent flying wing for a smaller engine? Are there specific types of airfoils that would be desireable? Flat bottom -vs- semi -vs- full? Would the CG stay the same at 25-30%? How do you figure out the vertical stabilizer area? Are there any span -vs- chord considerations?

Or am I way out in left field with this one?

-Joe

MajorTomski

For most airfoils, the center of lift is usually behind the center of gravity. So a "normal" wing will tumble forward/nose down if not attached to the rest of the plane. YOu can counter this with a "reflexed" trailing edge, in essence giving it "up" elevator to keep it from tumbling.

So in theory add full span split ailevators to the TE of your new shortened wing, and it might fly.

build light

Joe, the man to talk to would be Bill Evans. This man is reknowned for his flying wing models, particularly the Simitar and Saracen series of flying wings.

"For example; John Doe crashes an airplane with a constant chord wing, destroys fuselage and one half of the wing. Would it be possible to saw off the bad portion (and any dihedral) and build a decent flying wing for a smaller engine?"
Certainly! In this case the constant chord wing is known as a 'plank' wing. Both constant and tapered can be used.

Another example eould be the House of Balsa Stealth 1/2A kit.

Robert

ARUP

Hi- I used to fly redwood shingles as a kid! Bolt engine on the front and sew an elevator on the back. I drilled a hole or two to experiment c.g. I tied short string into hole near wingtip and whipped model around. It either flew or didn't. When I found the proper c.g. the bellcrank (B.C.) hole was drilled ~1/4" behind this reference point midwing. I bolted on the B.C., affixed leadouts and flew! When I was a kid I got a Cox Stuka and could whip that airplane around, engine out, until I fatigued too much to do it anymore. Saved fuel that way! We sure had fun!

combatpigg

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Joe, just about any wing can be converted to a flying wing. For many years I have been taking my "retired" C/L combat planes and converting them to RC combat. For example a .36 powered C/L plane is fitted with a pair of wing flaps and wing tips, CG set at 15-18% and there you go. I typically use .15s on the converted planes because I like the combat to be slow and with strategy instead of mindless high speed, head on jousting.
For simplicity, an airfoil that is symetric in front but flat from the high point back is the easiest to build, especially in batches. Make sure the flaps have generous chord so they can be seen by the airstream at low deflections, it makes for a smoother flying plane.
No need for any reflex or gimmicky airfoils, these planes will fly with zero trim if built with reasonable lightness.
The planes shown are a couple combateers with quite a few matches under their belts. The 1/2A plane is RTF at 13-14 ozs depending on how you equip it. It measures 36x9. The other plane is a retired AMA fast combat plane with some decorations and a ST.15...this one has a tight turn radius, it's fun to do all the old C/L Stunt Pattern manuevers with.

soarrich

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CP

Gees, I just posted somewhere saying I thought the CL fliers where the best builders, now I gotta rethink that.

combatpigg

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Rich, some C/L fliers are the best builders, but most of us are regular hacks. [8D]

For sport flying, [not combat] flying wings need a working rudder to be "real fun", otherwise the plane is just a "tool" for speed or for combat. The rudder needs to be stationed pretty far aft on a boom to be the most effective.

The "PatternBat" wasn't a true flying wing because it had an elevator stationed on a short boom, but it was a "wing" in spirit and what a blast to fly. This would make for a great project for anyone interested in building a fun plane for a .10-.15 to hotdog around.

ProBroJoe

All good info guys, thanks!

When I first started flying, my instructor let me fly a wing that he had. I have no idea what it was, who made, it, or even what size engine was on it, but it was a fairly short span "plank" with tip vertical stabs. It was fun to fly, and it's image has stuck in my mind for quite a while now. I think it had the word "combat" in it's name, but maybe he was referring to what it was used for??? (That was a few months short of 20 years ago.)

Fast forward to today, I have several wings from various projects/crashes and thought I could use one to whip out a flying wing of sorts. Of course all of these wings have either damage, dihedral, or both, hence the idea to cut a section out of the wing and use that. Which of course would leave me with a fairly short span plank-style, flying wing.... reminiscent of that plane I flew way back when.

What I'd probably come up with is a 26-28"L x 10" chord, flat-bottomed wing (modified Clark-Y airfoil). Don't want to cut any ribs, and just wanna whip something out is a flash - so I figured I'd use what I had, stick on some flaps, stabs, a tank, an engine mount, stuff in a radio, and go fly. I'm guessing a .10FP would be a bit right on this?

Or should I be looking for a different donor wing?

Raymond LeFlyr

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I have built several Simitars(sp) since the mid 70s. One of the keys to success with them is setting the CG in the 15 to 18% range. The airfoil helps )I believe) but the CG is the clue.

I think there's one called Bubbles (MA plans?) that is smaller than the typical Simitar.

The photo is one I made out of Fan Fold Foam for electric (ptui) power that is the same size as Bill Evan's Bug's Ear (as in; cute as - for TD .020 power origianally). It proved two things to me. One, that I could knock one out is a few evenings. Two, the airfoil isn't critical (I used KF-3). Three, dang flying wings can be lots o' fun!

soarrich

My Feedback: (98)

Here's a picture of my Missin' Pieces wing. It was my first electric and I was concerned about weight, so I figured if it wasn't there it weighed nothing.

Also four flying wing airfoils, I used the Scimitar on a sailplane I built in the 80's the S-5020 was used on Missin' Pieces.

Sessholvlaru

Looks great! I love the name, rather clever.

soarrich

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This is a wing I've just started, no wood yet, but it's designed, printed, and ready to cut.
The 3D rendering doesn't show the tips, or the vertical fin.

Sessholvlaru

Horton-ish. Nice.

jeffie8696

Hey Joe Ihave most of a Little Extra wing that might work.

jimmyjames213

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what programs are u useing?

ProBroJoe

Dude, you find a way to get it here and I'll build something out of it!

ProBroJoe

Oh, and that's what I'm pretty much considering doing, taking a crashed wing from a traditional aircraft and making a quick and dirty flying wing....

So CG should be 15-18%, but what about vertical stab area and placement?

hairy46

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Hey Combatpig will lead you in the right direction ckeck out his wing builds on RCU they are great! My personal little soap opera!

ProBroJoe

I just tore into the wing that I thought I was going to use, but unfortunately it's going to require too much work to make this wing half symmetrical about it's new center. There's center sheeting, top and bottom leading edge sheeting, and a widening rib spacing from root to tip to deal with. Oh well, so much for a quick and easy build. I may as well just build a new wing with everything where it needs to be.

So... anyone have an easy wing plan they wanna share - like something for around a .10?

combatpigg

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Joe, I've got plans for the 1/2A combat plane. It is 36x9. You would need to build a mount to support and position the .10. It won't give you as much in return as just a "wing-thing" with no working rudder.

I recommend the "Lil' Toad" delta as a great wing project. It's in the RCM catalog.

Does this photo give you some idea about proper vertical surface area and placement?

ProBroJoe

Actually CP, the 1/2A wing ya got there would actually do it to satisfy my curiosity! I'm just looking for something to bang out in about a weekend and terrorize the neighbor's dogs with (long story). I'm not 100% stuck on using a .10 - it's just that I have about a half-dozen of the little dudes here, as well as a handful (or two) of .049/.051/.061/.074 TDs and Norvels.

Truth be told, I have a Wonder kit here, but it's not exactly the "wing-thing" I'm after - right now. I'm more after the instant gratification that a simple wing can offer - the working rudder(s) can come later.

So, yea, I'd love to have a crack at the 1/2A wing ya got there....

Oh yea, the Batouttahell... it helps.... I think I have a enough info to wing-it.... (sorry) I just don't have much in the way of rib profiles to choose from, so that's where plans would come in handy.

combatpigg

My Feedback: (3)

Joe, do you have a good running .020? If so, I've got a wing for one that is gathering dust. It flew good on a junk .020 I got, but that engine is toast. Let me know, it would be easy to mail.

These photos should show how bare bones these can be built.

Wiggy

I am not being critical but the name is "LI'L TOAD"

I just looked at RCM plans to see what this looked like and their search engine did not find "Lil' Toad."

Since I never heard of this model I wanted to see what it looked like and this is how I found it.

Wiggy

ProBroJoe

I know, that's a huge part of the allure!

As far as .020s, I have a TD and a couple of PeeWees here, but no need to send your wing. I'm really looking forward to throwing one together myself. Do you have a .PDF of the plans that you mentioned earlier? Well, hell, frankly, plans aren't even necessary, just a decent rib pattern for something .061/.10 powered would go a long way.

Andrew

Attached is a barebones C/L wing, but with a little upsizing, it should work as a quick and dirty R/C wing. You might want to enlarge the tip plates a bit over the scaled-up version - they can always be cut back later. I would probably be inclined to leave the chord at 100% and add a bay or two to each wingtip.

andrew