The Vortex Ring State (VRS) is a dangerous condition for helicopters, occurring when the rotor descends into its own downwash, creating a turbulent vortex that causes a sudden loss of lift and control. This usually happens during vertical descents or hovering, especially at high descent rates and low airspeeds. Attempts to increase power can worsen the vortex, accelerating descent unexpectedly. To recover, pilots use forward cyclic control to move the rotor out of its downwash and reduce collect

Vortex Ring State | Helipress Magazine