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Reply to "NTSB to release Prem report on Air Evac crash"

lbself1, The rotor system on a helicopter is very flexible. The blades are hollow composite material filled with honeycomb. In flight during windy conditions it is normal to see the blades flight path move. Remember they are much longer than an airplane's blades. When a helicopter flies, the pilot is actually moving the rotor disk. The body of the helicopter is balanced to "hang" under the blades. We do not attempt to start our helicopter during a 15 knot wind gust spread due to the possibility of the rotor striking the tailboom during the start-up procedure. Normally this would not be a concern. When the throttle is @ 100 % the RPM's are high, the blades are at their strongest point and more rigid. If the pilot is struggling for control and the aircraft is pitching and yawing it would be possible that the blades could flex under stress and if the aircraft was pitching forward (nose down)with the pilot reacting and pulling back the disk would be pulled up in the front and down in the back before the body of the helicopter could "catch up"......We are only talking about a small area out near the ends of the blade would be able to strike the tail boom, but its enough.

Please keep in mind that these are all just possibilities. I just think that if everyone knows how so many things could have played a role it will help understand why it's so important to let the NTSB finish.

"If this were the case with a helicopter at low altitudes on low speed, one can only imagine how fast things could happen when faced with a similar occurance." unclegus.

AMEN, you are exactly right. Any hiccup at low altitude and no forward airspeed would be almost impossible to recover from....

I hope we all understand what happened in the end.

Bruce

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