"Barbs" wrote in message

In laymen's terms, could someone explain what the "vortex ring state"
(VRS) is in terms of a rotary-winged aircraft? One explication I'm
looking for is in terms of the V-22 Osprey....is VRS, with respect to
the V-22 Osprey, where the wake by one rotor is opposite of the other
rotor, causing a catastrophe in some cases?

In simple terms, Vortex Ring State occurs when a helicopter is descending so
fast that the movement of air up relative to the rotor is faster than the
rotor can pull air downward to produce lift. The result is turbulent
airflow through rotor disk and a loss of power.

http://www.copters.com/aero/settling.html

It occurs with conventional helicopters as well as Osprey. The major
difference is that most regular helos don't run into the asymmetric lift
problem that results from VRS in the V-22 if only one proprotor gets in that
state.

--�
Tom Schoene Replace "invalid" with "net" to e-mail
"If brave men and women never died, there would be nothing
special about bravery." -- Andy Rooney (attributed)