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The vortex ring state (VRS) is a dangerous aerodynamic condition that may arise in helicopter flight, when a vortex ring system engulfs the rotor, causing severe loss of lift. Often the term settling with power is used as a synonym, e.g., in Australia, the UK, and the US, [ 2 ] [ 3 ] [ 4 ] but not in Canada, which uses the latter term for a ...
As the V-22 descended to land it was dropping at 2,000 feet a minute, well above the prescribed 800 feet a minute. The speed caused the aircraft to enter an aerodynamic condition known as vortex ring state. In this condition, a vortex envelops the rotor, causing an aircraft to lose lift, in essence descending in its own downwash. [6] [7]
Spark photography image of a vortex ring in flight. A vortex ring, also called a toroidal vortex, is a torus-shaped vortex in a fluid; that is, a region where the fluid mostly spins around an imaginary axis line that forms a closed loop. The dominant flow in a vortex ring is said to be toroidal, more precisely poloidal. [clarification needed]
The Osprey is hard to fly, especially if the aircraft enters a vortex ring state (VRS), a condition that affects helicopters and forces them to lose lift when entering their own downwash ...
[24] [27] The USAF investigation ruled out brownout conditions, enemy fire, and vortex ring state as causes. The investigation found several factors that significantly contributed to the crash: these include low visibility, a poorly-executed approach, loss of situational awareness, and a high descent rate.
Main rotor disk vortex interference Weathercock stability Tail rotor vortex ring state. Loss of tail-rotor effectiveness (LTE) [1] occurs when the tail rotor of a helicopter is exposed to wind forces that prevent it from carrying out its function—that of cancelling the torque of the engine and transmission. Any low-airspeed high-power ...
If altitude permits, autorotations may also be used to recover from a vortex ring state, also known as settling with power. [2] In all cases, a successful landing depends on the helicopter's height and velocity at the commencement of autorotation (see height-velocity diagram).
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