Sep 06, 2003, 12:31 AM
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Detroit MI
Joined Jul 2003
550 Posts
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Woohoo! Guillows Aeronca Champ Flies!
After reading of a failed attempt to convert a 24" Guillows Aeronca Champ rubber-powered model to R/C, I sort of felt that this would be a worthy challenge. This kit was one of the first I'd built as a kid (back in the dark ages) and it flew well as an .020 powered free-flight plane back then..finding the same kit at a local hobby shop for 10 bucks almost thirty years later was just icing on the cake.
I left the kit stock other than adding 1/16" square balsa diagonal bracing between the fuselage formers & stringers, and a fiberglass dowel behind the leading edge of the wing.
I modified the fuselage so that the whole cabin/wing detached in one piece, locating it at the rear with bamboo skewers & brass grommets, and at the front with two pair of "rare earth" magnets from Radio Shack. Lifting the cabin structure away leaves a spacious "bathtub" to install the radio gear & battery pack.
For power, I'm using MPI "EPU 3" motor & gear drive (same as a GWS IPS unit) with 3.5:1 ratio, swinging a GWS 7x6 prop. Radio gear is the usual GWS Pico flight pack stuff. Battery is a two cell 700 mah Li-Ion battery.
AUW is right around 6.5 ounces, give or take, with tissue covering using one coat of clear dope with food coloring added.
I had intended this plane for indoor use, but it was so calm at the park tonight that it got to make it's maiden flight early.
Bad news is, on the first toss I managed to tear the landing gear off after over-reacting and slamming the grass..good news, after the gear was completly removed, it was very happy to make belly landings on the grass. With the stock wing and long throws set up on the rudder and elevator, the plane was a real handfull to keep in the air, and extremely fast (for it's power source, anyway). I reduced the throws as far as I could, and tried to remind myself to keep the stick movements SMALL. This technique worked for a couple circuits of the small field, but I ended up diving straight in from fifteen or twenty feet. Dunno if it was a freak gust of wind, a radio glitch, or just inherent instability, but it flopped on it's back and dove in hard. Damage was slight, broke the motor mount and did minimal damage to the plastic cowl. The magnet-mounted cabin really helps reduce crash damage pretty well.
I've rebuilt the motor mount out of 1/16 ply this time, and am rethinking the landing gear mounts..but I think this is gonna be a sweet little flier once it's sorted out. It climbed out with real authority, and responded very nicely to control surface movements. I'm happy with the results so far, especially since this is my first conversion attempt, and my first stick & tissue model in almost 25 years.
I'll post pics ASAP, I'm having some probs with getting my camera to load pics to the 'puter right now.
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Last edited by ZRX Doug; Sep 06, 2003 at 04:10 AM.
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