I worked in aviation-related business my entire life. Five years with Eastern flying the line, before it went belly up. Thirty-eight years running my own firm providing Aviation related services to Corporate Aviation Departments, Philip Morris, Mobil Oil, RJR, you get the idea. I provided Training, Safety, and Compliance. I spent a lot of time in 727’s G’3s, 4’s and 5’s. I avoided every and any form of a helicopter.
That was based on my unreasonable fear of them. I was aboard two that went down in Viet Nam, both UH1’s. Both under direct enemy fire when they went down. Both were successfully autorotated, one came down in a rice paddy and promptly fell over on its left side, thus trapping five guys under water. The Second one came down on dry land, we hit very hard, so hard that the transmission dropped down from the overhead and crushed the three guys in the middle, then it fell over on its left side.
Just to many moving parts under a great deal of stress, add to it, that at least in the case of the NYC sightseeing helicopter, poor design.