Welcome to Airball

Airball is our new aviation concept to help address the in-flight Loss of Control problem, and to have more fun and gain more insight into their flying. We do this by accurately measuring, and intuitively visualizing, the relative wind.

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Have you ever stuck your hand out the window while driving down the freeway?

The wind you feel as a result of the motion of the car is the relative wind. We pilots maneuver fixed-wing airplanes by orienting them properly into this wind as it blows past. In this photo of a performance by Sean D. Tucker, you can see how Sean angles his airplane into the relative wind (which is horizontal since Sean is doing a low pass across the flight line) at some pretty awkward angles:

Let's draw the axis of the airplane, and the relative wind, to highlight this effect:

Most of us never attempt anything nearly as extreme! But the principle is the same. We surf the air by angling our airplane into it. This is so important, in fact, that we emphasize:

Every loss of control of the airplane is preceded by a loss of control of the relative wind.

The author of the 1940s classic Stick and Rudder tried to use illustrations of pennants, arrows and windsocks to help pilots visualize the relative wind. This was the best they could do back then.

Now let's pretend for a second that we can see the relative wind, and that it is a big arrow pointing towards your airplane:

What would it look like from inside the cockpit? And can we simulate that somehow? Well, it turns out, we can! And the visualization we've come up with is called Airball. It looks like this:

The ball represents -- diagrammatically -- what the relative wind arrow would look like from our vantage point in the cockpit. In the following table, we draw three common situations of the relative wind -- at fast cruise and low AoA; slow flight and high AoA; and yawed flight. If we imagine the wind as a blue arrow, you can easily see how that translates to the Airball display:

That's all there is to it. Well, we add another little detail. You know when you're coming out of a high density altitude airport and your plane is climbing sluggishly and you want something, anything, to confirm what you are feeling, to assuage your panic? Airball adds a true airspeed ring around the ball, to remind you of your situation:

To make all this happen, we have built a probe and a display unit. The probe can mount just like an action camera on the wing of your existing airplane. It has a 12 hour battery life and sends data over a wireless link. The display can be used inside your cockpit just like your favorite EFB, mounted temporarily where you want it. It is powered by USB, from a battery or a 12V adapter:

Airball is Open Source; we post our designs and software on our Github project here:

We invite you to follow our progess on Github and on this blog!

1 comment :

  1. This looks very interesting, sort of a 3D AOA. What do the marks on the display represent? Do you account for flaps? I see too many AOA systems which don't allow for flap position effects.