Oh! That was Tom's work, and I can't remember if it includes the model or not. But ALS has a parachute model, used on the Orbiter, which I've been meaning to try... we should probably try a combination of the two.
Anyway, the licensing on that will be GPL, I'm almost certain, as I think Tom was a big believer in open source being as open as possible. But it's worth checking one of his aircraft as a signpost to his preferred method of licensing.