ORIGINAL: ahicks
T.O.M., agreed on the control surfaces, but only after a couple seasons worth of hard learned lessons.
It looks to me like the directions for the size planes these smaller (but still very powerfull) gas engines are run in haven't quite caught up with the requirements the gas engines impose on the airframes. Unfortunately, rookies like me are following them assuming they'll work. From what I've read over and over again here on RCU, as well as experiences gained the hard way, there have been MANY maiden flight/early test flight disasters because of a lack of good information in the directions regarding (or maybe emphasis placed on)the issues you mention above? Like: At what point is the kit hardware not sufficient? Exactly how heavy is ''heavy enough'' - for my application? What does ''right'' look like?
My thought earlier was the 8-10'' pitch props wouldn't help this (lack of good directions) issue one bit. The faster speeds generated by them only increase the potential for flutter, and they aren't all that desirable a prop for 3D anyway.
Also, and maybe much closer to being on point, ground clearance issues may start popping up (using the standard gear) when you get into the 18, 19, and 20'' props. Just a heads up if that thought hasn't registered yet... FWIW
You bring up some very good points.
The first thing I'll say is the moment you switch from glow to gas, 2-56 hardware became a thing of the past. 4-40 minimum on everything. The nyrod control rods aren't really functional anymore because of the inherent flex they provide. You
must have rigid and stong control linkage. Slop free connections are another critical item. Flutter can develop if horn/linkage connections permit a lot of free movement. Using a couple of 2-56 screws to attach horns to surfaces generally needs to be changed to a diferent fastener. The bolt on horn
might be ok, but sheet metal screw fasteners come out pretty quick. No easy connectors on gas planes. Anywhere, ever.
Floppy and weak flight surfaces are no longer tolerable. Not because of flight loading but because the combustion shock pulses from the engine combines with weak surfaces and hinging and breaks things. On a personal level I don't think CA hinges should be used on gas engine aircraft but many manage to do just fine.
Prop clearance can be dealt with as long as there are no personal concerns with adding a shim plate under the landing gear to raise the height, or replacing stock gear with after market stuff that is longer and stronger than stock. Since gas engines often add weight to the nose, stronger gear could be desirable anyway.