Reducing aspect ratio is a common design idea used to increase performance in span limited model airplane classes with weight minimums. This was not so much a factor last year as there was no weight minimum. AMA CLG classes have a required maximum chord of 3", but SO does not. Increased chord on SO gliders means increased wing area. If this can be accomplished without increasing weight above the 3 gram minimum, you have reduced wing loading. See plans of AMA classes like: P-30, F1-D and Limited Penny Plane. These are rubber band classes, but the concept is highlighted. All of the successful designs in these classes are low aspect ratio compared to similar classes without span maximums and weight minimums.
For very slow flying indoor rubber powered propeller airplanes, such as Limited Penny Planes (LPPs), the wing chord can be as much as 30% of the wing span. They have built up wings covered with delicate plastic film. The leading edge (LE) and trailing edge (TE) of the wing of an LPP are normally straight (perpendicular to the longitudinal axis of the motor stick) except for some straight taper on the LE of the upwardly canted tip sections.
A CLG typically has a solid balsa wing so that it can be launched at over 50 mph. The LE of the wing of a CLG often has a continuous curve from tip to tip. Look at published plans available on the Internet that show aspect ratios that are appropriate for small CLGs, such as the plan for the Feather Shooter.
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Found this for Scholastic, Chuck Markosscience8 wrote:This is for a friend. I was wondering where I could order the scholastic kit and the Stan buddenbaum kit and if both are adjusted to the new rules. Links would be appreciated
http://www.amaglider.com/?p=view&a=cmar ... r-kit-2014
Let us know how it flies if you get it. Not sure if anybody has tried it yet...
I agree with calgoddard too that the Feather Shooter is an excellent wing planform design. Other elements of the design like the method of creating the wing airfoil by reflex sanding undercamber and a wing highpoint thickness of 0.038" out of a 1/8" thick sheet might be quite challenging for a beginner. My favorite AMA design is the current national champion glider by Bill Gowen called the WIF7. Bill posted a plan for a simplified version of this glider that met the 2013 Science Olympiad rules on the Hip Pocket Aeronautics forum last year.
I do definitely believe that the event designers have created an excellent opportunity for creative solutions this year by adding a weight minimum of 3.0 grams. For low ceiling competition (less than about 50'), many modifications of AMA style designs should be considered, including: airfoil, planform, aspect ratio, etc. See Bill Gowen's AMA category II CLG national record holder plan also posted in the Hip Pocket Aeronautics forum. Have fun and keep building and testing and solve the canard design!
The answer largely depends on the ceiling height at the competition venue.ethancorvids wrote:Does anyone know roughly what times will get a medal for regional and state? What should I use as my goal?
O.k. Can you give examples? What would you expect for a 20ft ceiling? What about a 30ft ceiling?calgoddard wrote:The answer largely depends on the ceiling height at the competition venue.ethancorvids wrote:Does anyone know roughly what times will get a medal for regional and state? What should I use as my goal?
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