Planarian
DESIGNED TO MEET Bostonian Cabin West (14 gram Bostonian) rules, the Planarian is a canard-configured, rubber-powered model. Although the design may seem strange at first glance, there are good reasons for most of its unconventional features. My original Planarian had a successful contest career, consistently turning in times of about one minute under a 24-ft. ceiling. Other modelers who have access to sites with more clearance have reported times as high as 80 seconds for their Planarians. Despite its unusual appearance, the Planarian is relatively easy to build and trim, and is sure to raise eyebrows at your local flying site.
Free Flight: Duration
GREETINGS from the world of the aerodynamically strange. MA's publisher, Carl Wheeley, has once again asked me to write a guest column to keep the forces of conventionality and aft-mounted-tails at bay for another month. I'll start out by following up on two of the unconventional configurations which I discussed the last time I wrote a column. Since then, new wind-tunnel results have become available which show that they have some great possibilities for Free Flight. Swept tips revisited. A wing tip design which is getting a lot of attention these days is a highly tapered tip with a leading edge sweep of 60º. It has been theoretically predicted that these tips would reduce induced drag and increase span efficiency without the parasite drag penalty which winglets produce. The same theory predicts that a crescent-shaped wing could theoretically give span efficiencies greater than an elliptical wing.
