Nothing wrong with the type of STOL you're describing. It just means none of the ones mentioned so far fits that category, including the Zenair. You are going to have to design it to be very streamlined and aerodynamically clean with high aspect ratio wings, along the lines of Lancairs. Andy's designs are good start point, but you're gonna have to simplify the heck out of them. I often thought of enlarging Andy's design to around 80"-84" span, so I can put a good size gasser on it. However, the daunting task of cutting and shaping all the high-lift parts makes me shy away from it.

I do think you've got the right idea about the speedy STOLs, because the unfortunate fact is, there are already non-speeder STOL designs on the market. Just about any Stik-type plane with quad flaps will take off and land just about vertically in 10+mph wind. I had a couple of World Models Super Stunts that are great fun at doing exactly that. The simple flaps are crude but very effective.

Your kind of STOL will take some clever engineering to possess a ultra wide flight envelope and still remain relatively simple to build. My suggestions are to make sure you scale it large enough to:

1. make the Reynolds Number work in your favor

2. make the parts large enough to be less fragile and easier to shape and handle

3. most importnatly, allow high enough a price point to let yourself be profitable

I don't think .46 size is gonna do that for you.

I see you have found what Andy's favorite engine size is.

The manufacturing end of things we can handle... most people here knows we like to take the work out of the hands of the modeler (the tedious stuff anyways), and it should be more like that in today's market. Maybe thats why we don't see fowler flaps on anything. Manufactures don't want to produce it.

I don't think Reynolds numbers are really a concern on a design sporting 50" wide. Something 120" wide will benefit from the extra attention in Reynolds numbers.

Price point? That's a tough consideration. For many aspects that I'm not allowed to get into.

Bottom line, it seems to me that STOL designs are almost absent due to the complexity of producing such a product for a "narrow" market. I just wish there was more of it out there. I consider STOL designs part of the "funky" swatch of projects any one builder could bring to the field. Auto-gyros, Channel Wings, Canard designs, and all moving elevators are rare things at the field. I guess I'm getting tired of seeing the standard milk-carton fuse with an 8-ribbed wing strapped on with a rubber band. Sure people like it, and it gets some into the hobby without a hole lot of cash, but it just seems to me that the real neat funky planes are dying out.

I assure you it most definitely does make a difference. Without getting into the Fluid Mechanics, anybody who has flown, say, a 50" .46 size Extra 300 and a 120" 42% Extra can attest to it. And one does not need to go as large as 42% to reap benefits of larger scale, particularly on a design that will be using lift-enhancing devices.

Good luck with your venture.

Either you have good numbers based on airfoils that were designed for use in cords close to your particular application, or you have terrible figures to struggle with.

When you are dealing with something huge, Reynolds will play a little nicer. All I was saying is that dealing with things that are model-sized... well, we are all screwed by Reynolds issues. We fly in "soup" compared to airfoil effectiveness of a 4 meter sail plane going into competitions.

Scale effect: RN: cord[inches])X(speed[mph])X780 ... as we know AR: high AR reduces stall angle, but lowers the RN. Scaled foils produce low RN and therefore very low CL. Lower stall AOA & much greater profile drag (typically double or more). So unless you have a foil technology that is as effective as the Eppler series, it will be the same as picking through a pile of bald tires to use for tomorrows NASCAR qualifying.

Making Reynolds Number work for you... just isn't something you have control over. Either your foil allows you to get good numbers, or nothing.

Ken, go back and read what I said originally. I suggested that you should make the Re number work in your favor by sizing your plane large enough. Unless you are locked in on .46 kits, you should have control over the size, no?

But hey, it is only a suggestion. Feel free to do what you deem appropriate. You asked for opinions and suggestions, so I offered mine. Again, best of luck and hope everything works out good for you.

That's the thing... If the project calls for a 75" wingspan, then there are few things you can do to make it work... unless I make the cord real deep... and then if I... Hmm... neat idea.....

We will have to see what happens this summer. I will post photos of what becomes of it.

Ken, Why not look at a Maule, this is a noted STOl aircraft and the only kit I have ever been able to find is sold by Ikon N'west. The prospects of making a tail dragger or trike set up along with the possibilities of floats, gives a lot of latitude for the builder to decide on how to configure.

Nice Tri Pacer by the way. Couple members in our club are thinging of making winter project.



Jim Ogorek

A Maule? Hmm... interesting design. I like the tail, the windshield would have to be vacuum formed, and the cowl would have to be glass... but over all it looks sporty having so little dihedral. Yes, it shares a lot of the potential modes that of the Tri-Pacer... Floats, TD/Trike, or skis. The only part that makes me curious as to how I could present it... would be the webbed skin in front of the vertical stab. That might call for some real skill on the part of the builder to cover.

Aside from that, it looks nice.

I think I suggested the Maule Rocket sometime back. I dont think it would be too hard to cover the tail and fuselage top together. As a matter of fact the TriPacer fuse and vertical stab were covered in one piece. as is the Bellanca viking. It's done as two pieces with the seam along the dorcil centerline. A challenge perhaps, but doable. The Rocket was aptley named, it's takeoff was breathtaking. Full power, let off the brakes, raise the tail and go UP! With proper technique you could let the plane roll up on the brakes so that the tail came up befor the plane started to move. And that was with 180 hp. With 235 hp you could do it with 3 friends and a load of Coors.

Coors eh? "Kids, do not try this at home..."

I will have to look into what can be done easily as a process for those who would find it challenging. Perhaps recommending a specific covering process (Coverall, skilkspan... etc.)

Off topic: Fabric would be the way to go, however it could be done with film if you templated the pieces prior to installing them.

Aside: In olden times before Coors was marketed nationwide guys would fly to the nearest state where it was available and stock up. (Idaho in our case) The practice was so widespread in fact that Flying Magazine, about 1975, published the dimesions and weights of the Coors packages. That made the Weight and Balance calculations for the return flight a snap. It was tough but we always waited untill the plane was tied down before tasting the cargo. We liked the Maule because it was fast and could carry a lot of cargo.

When stationed in Pensacola back in the late 60's early 70's we used to take an OV 10 over to Texarkana and "pick-up" aload of Coors. Fly back high enough and Drop in for a landing, the beer was chilled just like coming from the Rockies.

Back to reality, the Maule I think would be a good next kit. Say in a 60 to 70 size 4 Stroke.

With all the options listed, One plane for all season's.

What is the dimensional specs for this beer runner?

Drexus, make yours big enough to cary a 6 pack of cans and the world will beat a path to your door. At 1/5 th scale the 42 inch wide cabin of the Rocket would be 8.4 inches. A six pack measures 5 X 5 X 8 inches and weighs 4 lb. 8 oz. The wing would be 79 inches with a 12 inch chord. In order to replecate the perfomance of the original I would suggest an engine slightly larger than a 60 2s or 70 4 s. The Rocket takes off with pilot an half tanks in 250 feet and climbes at 1500 feet per min. Stalls at 40 MPH with full flaps and cruses at 160 MPH at 75% power. Did you know that you can set the flaps at neg 7 degrees. They act as spoilers in that position.

Oh boy... I can see this project showing up at the next production meeting: A six-pack with wings!

It's so odd, I might just make one to test the loading on a wing design. I wonder what would be the most radical thing to put in the air... a lawn-chair? Oh that would be nutz funny!

Went into the AMA archives and read the article on the Maule Rocket mentioned in this thread. According to the author covering the tail to give the Dorsal look was easy. A little time consuming but if done correctly should produce a good looking job. Appears that you could scale down the size to the 79 inch wing and have a nice looking sport plane.

JimO,

Why reduce it to 79 which will keep it outside of the IMAA limits? If a model like this is going to be proceduced why not make it such that it also fits the "large-scale" category... adjusting dimensions for an extra inch of WS should not be a problem.

Vicar

First not all of us are in to the IMAA size though it does make sense. Plus there are a lot of us Sport Fliers that like would actually like a smaller size that would fit in our cars or take up less space in limited building areas.

Now if we can just get someone to draw the plans ina Cad program, we could go to any size. Think of the electric possibilities, can you say "park flyer".

JimO,

My point was related to the 79" size; it makes no sense to me to manufacture a 79" model which automatically leaves a segment of the possible buyers out. Of course I agree with you in the make it CAD so any size is possible but from the production point of view, "does one inch really matter" (pun intended!)

Vicar

Drexus, Airplanes have wings, six packs have handles. I mearly used the six packas a univerally known standard of volume. Even those who dont' drink have at least seen one. For those who want a larger vesion, remember this: at 1/4 scale this A/P will have a wing span of 98 and 5/8's inches. Thats longer than the bed of a pickup truck. This makes a one piece wing a virtual impossability. That may not be a bad thing from a production standpoint, but it does make engineering it a little harder. I love the big planes, but I find them a little tough to transport without damage. If we lobby real hard we may get Ken to make both sizes. While the Maule is not a 3-D bird it will hover in horizontal flight.

In for the lobbying on any size at this time. I don't think Ikon is making the kit. I have tried to call and no answer. I do know that AMA has the plans for the one built in 1982. SO let's hope we can get Ken interestred enough to make the Maule avialble in any size. IF you ever get to Atlanta GA area. Take the time and go out to the factory. Espically if they are delivering a new one and doing the instructional flights. Quite a site and even better if float equipped. Sure get's up in a hurry.

Wonder if Laser Lizard could scale the plans down and cut the ribs and fuse???

Sir,
1. Idea about manufactory stol plane is very good, because in USA making only 1-2 brands RC STOL...
2. I am thinking, that market can be very positive.
3. I have one idea / offer for Ken:
You can making ONLY WING-STOL and STABILIZATER-STOL< that they was good and fit for pop models< for example for Trainer 40.
Who need STOL plane can change only two units... I WILL BE FIRST! ( KEN, if interested e-m me [email protected])
4. Question for all: What can be better material for making slat and what kind of technology?
Thanks
PS. Forgive me for possible mistakes in grammer, because I am new person in US and beginner in field of RC planes; (I am former aviation engineer)
Thanks again

Hi fellows..

Well, guess what!!!

I just started building a 110 wingspan CH 801 based on the information published in the Zenithair website..

I am falling in love with this airplane.. When more progress is made, I will post pictures..

Allmetalplane

For those of you looking for a Wilga, Porter or Air Tractor.. check out this site, may have what you want. I ordered the Wilga kit a couple days ago, should be here soon. Won't be an easy build, but if successful, should be a heck of a lot of fun...

http://www.estarmodels.com/

Actually, Model Flyer has some plans for a pzl-104 wilga. They're not too good, but with some thinking and redesigning, you can build a wilga using formers and sheeting. I'm building it right now.
And yes the "wilga" does mean something It's a name of a bird, the golden oriole