How I plan to kick your butt next season ;-)

So you got a hot plane, eh? Tell us why you think you're gonna be Top Gun this year!

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cipoll717
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Post by cipoll717 »

Gary,
great work- I love it. One thing i would encourage you to consider is 'robustness' of a wing design. We all know that the design is highly optimized for the specific design, but in reality, the problem we have is that combat wings dont stay optimal. By far, the best flight is the first. Once it crashes, warps, and ages, it deteriates. Is it possible to get an optimal design that is more robust to the type of deformities that occur in use? I agree, you may take a hit in optimal 'out-of-the-box' maximum performance, but this is really only a SMALL part of the overall objective for a great combat wing.
gsjames
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Post by gsjames »

A very good point, Mark! You are correct in that our actual wings are FAR from being what we think they are, especially after a couple of rounds flying against Evan and Lee... That's one of the reasons that makes me think that the E203 isn't all that bad. It seems to have a very "flat" stall on the computer which makes me think that it is probably insensitive to distorted geometry, i.e. dents, etc.

Almost every wing section has the same "slope" to it's lift curve, unless it is really bad. The theoretical maximum slope is 2xPi per radian, or about 0.11 per degree. That means that it's really the zero-lift camber and stalling behavior that determines the maximum lift that any particular section can generate. I'm trying to delay the stall a little longer to a higher angle of attack in order to gain a little more max lift, but I eventually have to "pay for it" in a more abrupt stall. If I really pushed it, the lift would be higher, but would drop off like a safe when it finally let go. That's probably not a behavior that we would want although we could make a reasonable 3D wing by adding a few degrees of washout. These airfoils seem to start the stall at the trailing edge first. Keeping the airflow attached to the trailing edge a little longer results in higher max lift, at the cost of increasing drag. It may or may not be a worthwhile tradeoff.

The stuff that I am working on is pretty insensitive to geometry changes (dents, etc) so I think I'm pretty safe there. Having worked with CL combat models for many years, I have a reasonable feel to the inaccuracies in going from "theoretical" to reality. (there's a good joke there somewhere, I think) I'm going to play with this stuff over the 'off season' and see if there is any noticeable difference in performance of the actual airplanes. One of the nice things about the Battle Axe design is that it allows one to change out wings very easily at the field to be able to do real-time testing. Chris Quinn really has a masterpiece in that configuration.

Will it work? Maybe yes... maybe no. But either way Evan and Lee will still probably beat me[:(]
Hat Trick
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Post by Hat Trick »

I used to use flap linked to the elevator function on the older airfoils but when the newer airfoils came out it didn't seem to make much difference anymore so I stopped doing it even though I always use 2 aileron servos. I haven't tried it for a while. Might be worth a shot! Tight turning without a stall is always a distinct advantage in a pursuit style engagement.
Bruce B
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Post by Bruce B »

<blockquote id="quote"><font size="1" face="Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote">Will it work? Maybe yes... maybe no. But either way Evan and Lee will still probably beat me<hr height="1" noshade id="quote"></font id="quote"></blockquote id="quote">

Dont forget about Ben bajema.you had to leave early last time and didnt get to see, but this kids a player.I plan to be more competitave next year too
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