airplane design

Thanks to all who took the time to reply.

I guess more info about where I'm headed would've been helpful. I'm not sure but precision aerocatics is calling my name more loudly than anything else.

I'm sure I'm like a lot of guys out there who want to personalize their plane rather than build someone else's kit.Although the "Cardinal" really looks great!

I would like to have a basic understanding of what the effects of (I can guess at some) changing the CoG are, thicker airfoils vs thinner, shorter distance from wing to elevator vs longer. etc. In this way, when I do start monkeying around, or when I'm trying to trim an aircraft, I might be in a better position to judge where I'm going wrong or right.

Thanks to Ty for his offer of old articles. I think that'll be a good place to start.

Chris. What we tell people in the club is "DON'T TRY TO RE-INVENT THE WHEEL" Kitted planes like the Cardinal WORK, as the TWISTER, SV-11 and so on. Doing your own design is fun and time consuming. Use MODERN Numbers and you'll be happy. PA is FUN that's why I'm doing it. However, I don't have the time or effort to lay out my own plane. LIKE WE ALL SAY (KISS)
Keep it simple stupid.
Scott

Hi Chris,

At the risk of seeming to blow my own horn let me suggest a couple of things if you're truly interested in designing your own stuff.

First of all, I concur that joining PAMPA is a must for anyone with a yen for precision aerobatics. Send my wife Shareen (the Sec/Treas) a E-note for info at the following address :[email protected].

Better yet simply send a check for $25.00 (U.S. membership) to: 158 Flying Cloud Isle, Foster City, CA 94404. We are in the middle of renewals for 2002 and the mebmership year is January to December. Therefore, if you are interested in starting immediately I'd suggest the following. Send $50.00 for both 2001 and 2002. You won't lose any benefits since a late in the year new member receives all the STUNT NEWS magazines for the year. Thus, you'd receive a separate package with the first five issues and the November/December issue with the normal distribution.

If you're not familiar with STUNT NEWS or worry about its value just ask the guys on line here at Stuka Stunt what they think about it. I think you'll find unanimous raves. It's probably the single best special interest modeling publication in the world.

About design. Over the years I've published a number of lengthy articles dealing spedifically with the design and trim of stunt ships. These include construction articles on several well known and successful designs such as the Imitation, Excitation and Trivial Pursuit and the Doctor. In addition, design specific articles in both STUNT NEWS and my monthly column in MODEL AVIATION from the late eighties include: The Design and Trim of Controline Stunt Models, Fly Like a Champion, So You Want To Win, Huh, and others. Reprints of these articles are available at very reasonable prices from PAMPA Products, one of the benefits of PAMPA membership.

Unfortunately, I don't know of a specifically published "book" on C/L stunt design. The best resources are probably reprints of the better articles published over the last 50+ years.

Chris,

Hmmmm. Apparently you can't specify an E-Mail address in the forum. Guess you'll have to mail us a note.

Sorry.

What e-mail address were you trying to post, Ted? There shouldn't be any problem posting an e-mail in the message unless you hit one of the emotion icon short cuts. (See notes above when composing your response). Just remember, the board uses Pearl so a few changes have to be made. For HTML tags you need to use brackets instead of <> . Put in the wrong one, and you get that "devil guy".

Leonard Neumann

As Scott has said, if you take a half dozen of successful designs you will find they are all quite close in percentage of tail to wing area, moments, etc. Sure, you can vary a little, but don't vary a lot. The "numbers" have been arrived at for a reason and if you change them too much you will make things worse, not better.

What I would suggest is take a proven design and, if you want do "do your own thing" just change tips and fuselage outline and the like. Keep the areas essentially the same, keep the moments essentially the same, and you will be happy. But make sure you put in a lot of adjustables like adjustable leadouts, tip box (even elevator horn if you can).

As to CG location, you can move the CG back and forth to see how it affects the airplane, but when you do, you will need to adjust leadout location and sometimes even tip weight. Some like the CG a little farther forward because it will "grooove" better. Some like it a little farther back because it becomes a little more responsive. But there is only a certain "window" in which you can move it effectively. Go beyond that and you can get yourself in trouble. Here, too, when a design specifies a certain CG location, it is best to put it there and make only slight adjustments beyond that.

Leonard Neumann

Designing your own without lots of experience will set you back many years, reinventing aerodynamics, controls and all the stuff that has to work together. And chances are, you'll fail. If you want a different "look", for whatever reason, start with plans or a kit and just tweek the styling to suit yourself. We call this "kit bashing", and it's been around for 50 years or more. Flying is more important than flying your own design, right? Steve

Designing my own airplane and having it fly very well is the most satisfaction I can get out of modelling. Having said that, I first needed to have considerable experience building and flying "known to be good" airplanes. Two reasons: first to develop the ability to fly a good airplane in a respectable fashion, and secondly to know what flying a good-flying airplane is like. Otherwise how could I know if my designs were any good?

The orthodox stunt airplane is that way for a number of reasons. If you have some understanding of these reasons, then you have a basis for designing an unorthodox airplane that may work pretty well. At least better than your flying buddies expected it to.