Civil Tilt Rotors
For FH1100 and SASless,
Sometime ago Nick Lappos offered some thoughts about whether the Marana crash was VRS or in reality quite a different aerodynamic situation. Maybe he will respond with that discussion here. In any case, postulating a vortex ring state boundary at 40 KIAS and -800 FPM and stating that boundary exists essentially for all helicopters flies in the face of all of the undersigned's experience in attempting to force helicopters into this state.