On Friday, June 15, 2018 at 9:42:35 AM UTC-6, Charlie Quebec wrote:
...even if only 20 seconds of high power to accelerate for self launch.

Nope, supercaps absolutely not helpful.
You need enough power for a safe climb rate for several minutes.
And that much power already provides more than adequate acceleration.

Forget the supercaps for this application!
BTW, some electronics I designed flying in produced gliders uses supercaps ;-)