Roy wrote:
It has been suggested that an RV9 with a big motor (160-200hp) would
be great to do the job.

Anyone else considered this approach?
We are not a commercial operation and dont have to pay our pilots.
There is no insurance problem so this solution has some appeal. ie
new airframe, easy repair & maintenance.

If you are in the US, towing gliders with experimental aircraft is
prohibited by the FAA. I can't remember the exact place where it is
spelled out (it's probably in an AC), I'm sure someone else will know...