Welcome back to Helicopter Lessons in 10 Minutes or Less!
Check us out on Facebook for more Helicopter videos!   / 10minlessons  

Check out my ebook covering this and more! Get your copy on iBooks: http://itunes.apple.com/us/book/id144...
or on Kobo for Android, Windows and Desktop users: https://www.kobo.com/us/en/ebook/heli...

This episode will cover Part 1 of a 2 part video covering Vortex Ring State / Settling with Power. I tried to keep this all crammed in 1 video but I felt like there is just too much information that would be left out. I hope you all enjoy!

What is a Vortex Ring State and what is Settling with power? Many people use these terms interchangeably and, although they aren't exactly wrong, these terms do differ. Vortex Ring State refers to the condition where a rotor system has a secondary set of vortices in addition to the standard wing tip vortices. This second set of vortices when combined with wing tip vortices creates highly disturbed/turbulent airflow through the rotor disk causing massive rotor inefficiency. In this condition, a helicopter can experience Settling with Power. Settling with power simply means the helicopter can "settle" or descend despite having the necessary power applied for flight. So a Vortex Ring State causes Settling with Power much like an iced road causes skidding. They're not exactly the same thing but usually always associated with each other.

This effect can progress naturally as upwards rates of descent change how airflow moves around the disk. As explained in Airflow at a Hover (   • Airflow at a Hover in Helicopters  ), the normal flow of air is downwards through the disk. The downwards airflow is more pronounced at the blade tips than the blade roots due to the rotational velocity and distance from the mast. As the helicopter descends, there is a point where upflow of air overcomes blade pitch and rotation around the blade root. If this is allowed to progress, a second set of vortices can form in this region. This is what is known as a Vortex Ring State.

As a pilot you'll experience this effect as an increase in vibrations (due to unequal lift and drag across the rotor disk), reduced Cyclic authority, and a loss of collective pitch effectiveness. Instead of arresting the rate of descent with collective application, you actually increase the rate of descent by exacerbating the Vortex Ring State present in the rotor.

Check out Part 2 (   • Vortex Ring State / Settling with Pow...  ) to see what is required for a Vortex Ring State as well has what conditions are conducive and how to recover from it.

Once again I'd like to take a moment to thank you guys and gals for the feedback! I appreciate all your thoughts and comments helping me improve as I make more of these videos. If you enjoyed this video be sure to like and subscribe!

As always, safe flying.


If you're just getting started and want more information, pictures, and more explanations, I'd recommend reading the Rotorcraft Flying Handbook http://amzn.to/2ifPlnZ

If you've already got a basic understanding, and want to further your professional helicopter education with advanced helicopter concepts, I'd recommend reading Cyclic and Collective, by Shawn Coyle http://amzn.to/2ifQGLx