Der friends,

local R/C flyers over here have just been granted permission to do indoor flying in our brand new gym hall on a regular basis. Without thinking twice I promised the guys to show up with a couple of fast electric indoor c/l airplanes, trying to show off a little while teasing youngsters to give it a try.
Technically, I am thinking along the lines of a scaled down F2D flatplate airplane (approx. 20 in span?) made of 6 mm (1/4 in) Depron, flying on 6 m  (20 ft) spectra lines. The problem I have now is that I do not know what power train setup to use and I really would appreciate related suggestions.

Thank you an kind regards,

I was thinking you might want a soft spinner to save the motor shaft -- it hadn't occurred to me that you might have to worry about the floor.

Combat with LiPoly batteries?  I would be concerned about a prop slicing into a battery and the resulting fire that might start.  I watch fast combat all the time and midairs are quite common.
Andy

It would be a spectacular midair if one of airplanes blew up!   But really what are the chances?  Has anyone taken an old LiPo that will still hold some charge and poped it with a 22 round?  would make for some intersting vedio.