I had to go with none...ever[X(]

I have ben flying helis for 5 years, and in those 5 I have never driven one in due to pilot error, although I have had 3 due to mechanical falure

nothing big though. I would much rather drive one in from dumb thumbs over a falire though......just have to wait until it happens, because it WILL happen

Hopfully not any time soon.
Colin