Original Message

The only reason VRS exists is the cavitation of the air mass under the helicopter rotor system.  That is why you fly out of it. #1 in my earlier post.  I.E. engine developing POWER to the rotor system creates cavitation.  If you are flying forward off of the cavitated air and you have a tailwind it keeps the cavitated air under the rotor system longer.  I don't know how to explain it any simpler.  Best methods are knowledge of the problem and avoidance.