Backward Blade Your post created no offence nor was it without merit. The rules are different around the world and I know nothing of what certification or approval steps that Red Bull has taken outside of the US. I merely wanted those interested to know that Red Bull went to great engineering lengths to prove to the FAA they could do their routines safely and the US pilot, Chuck Aaron, approached his training and conducts his flights in a manner that is most professional.
Great controversy surrounds the issue of aerobatics in helicopters and discussion that question when, where, how, and under what authority these maneuvers are conducted are always of considerable merit. Please accept my apology if my reply to you seemed as if I was offended.