Well, there I was, lying low because I didn't even understand the question, and no-one else from this side of the pond did either.
But it's reminded me of something. When I was in Russia back in 2002, you got a HUGE amount of shuddering when bringing the MI-8 to the hover. It was scary!
I tried to ask why, but no-one spoke enough English to do any more than assure me it was quite normal. So, why particularly in the MI-8? Nick???