RE: Nitro models pusher Bobcat?
Buddy of mine has a Balsa USA Enforcer with an OS 1.08 strapped to it's tail. He installed a copper "U" pipe fitting into the wing and has it exiting on the bottom of the delta wing, facing aft. It's a slick setup and your post just jarred my memory of it. It's the 3/8" copper fitting and it matches up to his exhaust hose nicely. He may have used 2-90 degree elbows and soldered a short leg in between to clear the thickness of the airfoil, I'm not sure.
Anyway you look at it, it's way kewl.
Almost forgot...recv'd my Hitech MG125 thin aileron servo today. It's **tiny**! 42oz torque from such a small servo...drops into the framework of the Bobcat stabilizer with lotza room to spare. The output arm is rather short-ish but at the speeds this thing is supposed to achieve, slight deflection should be all that's required...Afterall, this ain't no 3-D machine :-)
Pardon the crude drawing but you get the idea, I'm sure, lol
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