Wat is Vortex Ring State (VRS) in helicopters ?

Question

Wat is a Vortex Ring State in Helicopters landing stage ? can some one explain and define in detail ?

Answer 1

A vortex ring state (VRS), though, involves a toroid-shaped path of airflow circumscribing the blade disc, as the airflow moves down through the disc, then outward, and then down through the top again. This re-circulation of flow can negate much of the lifting force and cause a catastrophic loss of altitude.

Answer 2

Better known as "settling with power". Creates a downward moving column of air. When you pull more pitch, increase collective, to check the descent you increase the downard speed of the air which makes it worse. The only escape is forward cyclic and fly out out of the column.

Answer 3

as explained above, vrs is more commonly known as settling with power. three things need to be present for this to occur. 1. you must have zero air speed 2. the power setting needs to be between 20 and 100% 3. you must be decending at a rate of 300 feet per minute or greater.

once these three things are present the helo will rapidly decend in its own downwash, you loose a lot of altitude very quickly. the controls also feel very mushy.

also, as stated above, if you attempt to increase collective to counter the decent, you will worsen the situation.

the good news is its pretty easy to overcome. the easiest of the three factors to get rid of is zero airspeed. most pilots will favor forward cyclic to increase airspeed, but the truth is you can choose any direction, even backward. if you are landing though, you should be facing into the wind and forward is you best option. as you correct your airspeed, you should also lower the collective, if practicle