Originally Posted by
doxilia
Matt,
I think you struck a key point: wing loading. If the Kadet Sr really has 900 squares and can be RTF at 5 lbs, that puts it at around 8.3 oz/sq ft of loading which is practically foamy class.
I can't think of many classics that would adapt well in terms of super light construction that would yield a reliable aerobatic model. I doubt that a Kadet could be put into a violent snap and recover structurally sound - not that the model would likely enter the maneuver. However, I think that a 40 class model could be built to 4 lbs or so with some 600 squares or thereabouts. Mike on his RCG Sabre build is in that ballpark (although his wing is smaller). At 600 squares a 4 lb model would fly at a little over 15 oz/sq ft which should yield a very docile model and still respond well to aerobatics.
Another classic that comes to mind that could be in that ballpark is the MK Thunder Bird 40. With a light engine and covering, it can probably be brought in at around 4-4.5 lbs on 8 oz of fuel. The wing could be easily extended in span by a rib bay. Not a bad looking model either.
David
Dave, exactly....power loading also. Power should be just enough for extended verticals on a 15 mph wind day. Not unlimited at half throttle in 30 mph wind as some of the stuff available today is doing.
5 lbs and a 40-45 go together like peanut butter and jam. Many moons ago I scratch built a 40 sized Curare from a plan appearing in MAN or RCM, I just enlarged the drawing, fattening the fuse and increasing area, removing much of the thick wood. As I recall, it came out at just about 600 squares and around 4 1/2 lbs. It flew great with an old trusty KB40 on muffler. Talking about putting around at 1/3 throttle...really kool.
Back then we had large clunky servos of minimal tork and slow speed too. With today's gear, the same model would shed 8 ounces easy. Of course the model is long gone, destroyed in one of my moves. Maybe time to design another??