Nick,
There was a published engineering report prior to the first flight, that predicted exactly what occurred.
I think it is also very revealing, as you note, that so many of these huge machines were constructed but were totally impractical and had no viable application - they simply weren't thought out thoroughly. Once it was flying, you were sometimes left with more problems to tackle than the initial design work itself!
Although I never saw this machine in real life, I do know a couple of people who did and they said that they were not surprised at the outcome just from looking at the way it was constructed.
The evolution of large helicopters was spectacular and rapid, considering the short period between the first production helicopters and some of the gargantuan models that followed. Of course, like all Aviation development, the lack of suitable powerplant's was really the controlling factor in all of these developments. The Sikorsky CH-37 (S56) was unbelievable in both complexity (and maintenance demands)
, but the very last of the large piston engine helicopters as they struggled through material and technological change, must have been one of the most exciting times ever in the helicopter business.
Piasecki Vertol were of course in the midst of this. During the transition period between piston and turbine engines, so huge boundaries were passed. I think that one of the most amazing looking helicopters ever produced came out at that time. Although not a success, the Piasecki YH-16 epitomises 1950's design, architecture and style. Not only does it look like something from a science-fiction (or Godzilla) movie, it clearly demonstrates the amazing resources and drive that was apparent in the post war aviation industry.
http://www.russian.ee/~star/vertigo/...ki_h-16-r.html
Not meaning to detract from Dave's original thread - amazing how these topics take on a life of their own!