Originally Posted by bearfoil
Please do check your math.
Yes, thanks for the heads-up.
Circumference is 2 x Pi x R, and I want twice around (2 x 2 x Pi x R) to be greater than 340. I get R (now :-) ) to be about 27 m, a little more than the 7.5m I originally wrote. I have no idea how that happened.
Even so, 27 m is less than the semi-wing span of A330/40 or Boeing 747 / 777 aircraft, which is also attained by some recent high-aspect-ratio smaller airplanes such as those used for HALE-type research projects, none of which you would want to try to snap-roll.
PBL