To: SL
When I worked on helicopters many moons ago we busted our humps trying to keep the blades in track on the four types supported on our base. That included the tail rotors. Long after that Sikorsky designed a built in track scan system that would allow you top track blades in flight. Many companies have developed systems that allow you to not only track main and tail blades but to balance them as well. With all of this technology available it is up to the maintenance personnel to use them.
I had a ride in a commercial S-61 that had a blade so far out of track that it would jar your teeth. When I got off at LAX I told the mechanic and he said they would catch it at the next periodic maintenance. Three days later that same helicopter lost a blade in flight and several months later a sister ship threw a blade. The blade loss was not due to the out of track but the condition might have accelerated the situation that eventually caused the blade loss.
My philosophy is to minimize any maintenance and or flight problems keep the blades in track.
