FH1100: should the Army and Navy and Marines have stopped flying Hueys because they can experience mast bumping? (If flown in certain profiles).
Hueys are still flying, today. I learned about mast bumping during flight school in about 1981. It was roughly 20 year old information at that point. (Don't recall just when in the sixties that the issue was documented, but some of my instructors were Viet Nam era Huey drivers who discussed how important knowing that limitation was for tactical flying ... )