I would like to hear why everyone thinks this is so dangerous, if you can get a fully inflated canopy to the edge of a drop (a building doesn't seem good for that), what things would you be worried about going wrong? I can imagine dropping a few feet before the canopy starts flying properly and maybe having a 180 in the meantime. What other dangers can you think of? I would like to do some ground launching too, for "free" canopy/accuracy practise.
Definitely go from a grassy hill first, it's a lot harder than it looks. I had an x228 (7 cell) out last week trying to launch it from a hill but no luck, i was getting it inflated but even on a hill with about a 45 degree slope i couldn't get it to launch, i concluded that it's useless without a bit of head wind to help with the pressurisation (not ideal for this location).
I was talking to a guy about bladerunning, where you fly a high performance canopy down a ski slalom course and he was saying that they are ground launching at the top of runs, maybe post on one of the skydiving forums to see if anyone knows about that, should be more practical than a paraglider.
