RE: Learning to use a hi-start
On 50 feet of 3/8 hosemonster I would have about 200-225 feet of line. If you have a head wind of over 10 mph you can probably add another 50-100 feet as the breeze will take the plane up like a kite. The rubber might never even fully contract.
I have launched my supra on a very stron hi-start in 12 mph winds and it goes so high and the rubber does not fully contract. I just keep adding line till the launch seems to run out of gas too soon, then I take some off. Takes a little experimentation to see what is the optimum line lenght.
I normally launch with a pull that is 4-6X the weight of my glider. On my supra ( 4 pounds ) I iwll launch at 24 pounds pull in light conditions and about 20 pounds of pull in the wind since the wind helps take it up.