Building a plane using 30cc Homelite weed wacker- is this reasonable? Need your thoughts on this one.

Sure, if you scaled it up enough. Anyone got an opinion on this idea? mk (i bet it's on a floppy somewhere)

Motor mount details are usually left as an exercise for the reader.

So, yes.

Actually, this is a good point -- just about any 'trainer' should do as long as you scale it up to around 7-9' wingspan and keep it light. So a

60" span .40 sized trainer, with all the dimensions multiplied by 1.5, would work a treat.

Do a web search for the "RCM Trainer" Back when folks still built their own trainer it was very popular, and it should work well for this.

"Lee B" wrote in news:DFSUl.2098$ snipped-for-privacy@nwrddc02.gnilink.net:

Here's my story.....

Less than two months ago I went and bought a Multiplex Easyglider foamie powered glider. First flight was alright, but I had a rough landing that broke up the nose. My first day was in 10+ mph gusty winds.

Next weekend all was fine. Did several approaches and then some landings. Later flights grew till I was catching thermals and staying up on one battery for over 50 minutes.

Last weekend I was doing 'endless' loops and other aerobatics; hammerheads, tailslides, barrel roles, etc....

Weekend before that was flying a friends twin engine pusher 'jet' and impressed him with my fighter like flying.

Previous flight experience? Been flying rc helis for a little over a year (fly a Blade 400 right now). Just had a minor crash after nearly 50 clean flights, but still having trouble doing more than just flying back-and-forth.

Previous to that? About 25 years of Microsoft Flight Simulator. (although I've switched to X-Plane recently)

Brian

Pursuant to that:

"Onestep", from 9-81 "Model Aviation". 62 inch span for .15 power (light!). It has a fairly high aspect ratio, you could scale it up 2x just by doubling all the wood sizes, build it light & fly on quiet days. You'd _probably_ want to scale it to 8' span, instead, with doubled wood sizes.

"Pine Baron", from 6-83 "Flying Models". Slightly over 6' span, so you'd want to scale it up to 150%. Designed to maximize the use of pine, so you could save a few $$ on wood if you have a table saw to rip the dimensional pieces with.

Or just about any kit-built trainer that has detailed enough plans (I.e. the Goldberg Eaglet, scaled up to 200% or a hair bigger, and with revised fuselage structure).

No matter what you do you'll need to scale up some plans. Just pick something that has a high rectangular wing with a flat-bottomed airfoil and simple construction. Modify it as necessary to take the engine, and make darn sure that you can find someone willing to take it up for you for the necessary tuning and tweaking flights.

And wasn't there a "Nosen Trainer" that was specifically designed as a giant scale trainer?

I always liked a Bridi kit but the high wings are tail draggers in the 1/4 scale Take a look. mk

Yes and no. There is/was a Nosen Trainer, but it was a GIANT scale trainer rather than a giant scale TRAINER. More to teach folks how to do giant scale than how to fly. This bird dates from long long ago.

Here's a question for you, actually 2: If I took a small CL plane that had a top wing like a Piper, could I scale that by blowing it 200 or 300%? By that I mean if the wing was 20 inches, then multiply each measurments by 3.6 to get 72 inch wing span for example, would it fly?

Am I right to say that the planes with top wings, are usually meant as trainers since they don't seem fast?

I'm not looking to do aerobatics with the plane. I just want to see it fly in circles, take off and land without too much damage, not necessarily in that order....

Dany

Tim Wescott wrote:

>

û,somewhere, a file of a trainer that can be scaled up to whatever size you

On 31 May 2009 21:51:20 GMT, snipped-for-privacy@the.candy.store.com (Dany) wrote in :

5 minimum:

Throttle Rudder Elevator Aileron Flaps

I like having extra servos for my bigger planes.

Throttle Rudder--2 Elevator--2 Aileron--2 Flaps--2

So that makes 9.

Balsa wood.

1/8" bending poplar (a.k.a. "lite ply").

1/4" ply for the firewall.

Maple for the landing gear mounts.

Tie the maple well into the fuselage structure. Tearing landing gear out is no fun.

Hundreds, if not thousands.

I think the AMA may also have a plans service.

Google "RC plans" for more sites.

There are also some good books on designing and building from scratch. If you insist, I'll get you some names tomorrow. Not tonight.

18" to 20". Go for a flat pitch. 18x6 to 20x6?

You'll have to fly the plane to see what works best.

Best place is in the wing about as close as practical to the flap. Torque rods rob torque.

Get a flight simulator to use on your PC.

Get a friend to flight test your plane for you.

You might build a trainer first to get some idea of how the pieces go together. I was moderately happy with the Sig LT-40. It has a flat airfoil, however, and doesn't last long as a trainer for more advanced maneuvers.

Marty

The correct terminology is not top wing, but "High Wing".

Yes, high wing planes tend to be more stable than low wing planes, if they are identical in the other ways that determine the stability of the plane.

If you want more stability in a plane, in the direction of bank, you put more "bend" in the wing, called dihedral. If a wing is straight across the top, it will not have any desire to right itself. If it has about 176 degree angle across the top, when it banks, it will tend to try to go back to level by itself.

Another factor is the type of airfoil. Google "clark Y airfoil" and you will see that it is flat on the bottom. That provides good lift at low speed, which is what you want for a basic trainer. When scaling up plans of real airplanes, modelers usually find that enlarging the horizontal and vertical stabilizers by up to 20 percent. A pilot onboard a plane can make instant reactions to keep the plane flying straight, where a RC pilot can only look and react, which is harder to do. The enlarged surfaces help it to fly more by itself.

The bugaboo about just scaling up plans is that will give you the outline, but not the construction details about things like how big the main and tail spars need to be, how to fasten the wing to the fuselage, how to fasten the landing gear to the fuselage, how the angle of the wing and angle of the tail and angle of the engine, and so on, that you would have to guess at. I personally think you should find a plan to build, that already has these details worked out. Perhaps a plane that does not look like a real scale plane would be good for a first plane. Many times, a fuselage with no cockpit is called an ugly stick. Try to find some plans for that type of plane.

All kinds of plans for planes are out there waiting for you to find them..Keep looking, and you will find something to build to fit your needs, I will bet.

Airplanes which fly easily on CL aren't necessarily going to fly well for RC. You want to pick something designed as an RC trainer.

Yes and no. Nearly all trainers are high wing, but many high wing aircraft aren't suitable for trainers. Even scale models of full-scale trainers won't be as good for a lot of reasons (mostly having to do with ease of building and the fact that what's easy to fly from inside isn't necessarily easy to fly from outside).

You want to find a plane designed as an RC trainer, either the right size for you or that you can scale up. You'll vastly increase your chances of success if you do.

Excellent answers, Tim and Jim.

Ed Cregger

So this is a website devoted to SPAD (simple plastic airplane design) and on it are detailed plans to build not only a 30cc trainer but many other fantastic planes that are nearly indestructable, easy to build and just plain old fun to tinker with.

I am building a plane around a 30cc echo chainsaw engine with a high lift 6' wing out of coroplast and Aluminum and good god its a hoot

On Fri, 19 Jun 2009 05:07:28 -0500, donnbauer wrote in :

Good for you!

Let us know how it all turns out ...

Marty

Spadtothebone is a great site. It is, unfortunately, not being updated at this time. Most of the active responses now show up on

www.Spadtothebone still holds most of the older and very useful plans, though. Rich