In article , "Flemming
Torp" fletopkanelbolle2rp.danmark says...
Being a sailor with no experience with aviation, I do not
understand the helicopter analogy.
In my opinion, a helicopter driven by the engine corresponds
in my understanding to a sailboat, where the propeller is
set to drive the boat *backwards* ..... When the propeller
on the boat 'gets the chance' to run without the force of
the motor, that is just sailing forward by sail, I expect
the propeller to turn in the opposite direction ... that is
'forward' ... If that happens in a helicopter, I would
expect the helicopter to hit the ground very fast ... don't
you? I do not assume, that there is a lot of inertia in a
propeller or shaft en a sailboat - may be that is the case
in a helicopter, and that could explain the smooth landing
without the assistance from the motor - or I'm I completely
wrong here? ...



The boat prop continues to turn in the same direction as it did when it
was the method of propulsion since there is no change in direction of
the water flow. In other words nothing forcing it to counter rotate.

In the case of the helicopter technically you are correct and a reversal
of direction would change the rotation of the blades. However the rotors
are connected to the engine via gears and can only rotate in the "lift"
direction. When the helicopter starts to fall due to loss of power the
rotors, slowed buy the drag of gears and engine, are forced to spin in
the lift direction causing "drag" that slows the copter to a rate where
impact with the ground is, at least, survivable.



--
Mike G.
Heirloom Woods

www.heirloom-woods.net