Airplanes pitch, roll, and yaw. Boats do, too. But nobody ever gets all weirded out by somebody asking them about how to turn a boat. Maybe because it seems obvious, so obvious that nobody feels the need to label the movements. When it comes to airplanes it makes sense to label everything though, because unlike a boat, airplanes aren’t naturally buoyant. If you let go of the tiller on a boat, it just kind of floats along, meandering with the wind. If you let go of the controls on an airplane for very long, something unpleasant might happen. That’s especially true if you’re not all trimmed up to fly hands off.

We’ll get to the trimmed up part later. For now, let’s just consider the three axis of flight. They are pitch, roll, and yaw. Pitch, roll, and yaw movements are controlled along the longitudinal, lateral, and vertical axis.

See, there are only three axis. You can remember three things, right? Sure you can. Pitch, roll, and yaw. Longitudinal, lateral, and vertical. It’s a piece of cake.

Pitch is the term that describes the up and down movement of the nose. We pitch up, and we pitch down, and we do it along the longitudinal axis. Imagine a stick that runs from the tail of the airplane right through the center of the airplane and comes out at the nose. That’s the longitudinal axis.

Roll happens along the lateral axis. That’s the motion most of us refer to as a bank. When the wings bank to the left, so does the lateral axis. Think of another stick that runs right through the wings, from one wingtip to the other. That’s the lateral axis.

Now sharp eyed readers will notice the image from the Pilots Handbook of Aeronautical Knowledge included with this post shows pitch happening about the lateral axis, and roll happening about the longitudinal axis – the complete opposite of what I just said in the previous paragraph. Both descriptions are true, however. The difference is subtle but important. It all comes down to the words, “along,” and “about.”

Take a look at the image and see if you can imagine pitch happening about (or around) the lateral axis, but along (in line with) the longitudinal axis. If you held the stick that represents the longitudinal axis and pitched the airplane up and down, you’d see the connection between the word “along” and “longitudinal axis,” right away. Similarly, if you held the other stick, the one that represents the lateral axis, you could pitch the airplane up and down by rotating the stick one way or the other. That’s a great example of pitching “about,” the “lateral axis.”

That’s a key to any written test question about axis of movement. Make sure you know whether the FAA is asking about movement along the axis, or about the axis. Once you have that key term locked down, you can answer the questions about movement simply by just using your imagination a little bit.

The vertical axis is the easy one. It runs straight up and down through the center of the airplane. The airplane yaws on the vertical axis. In other words the nose moves to the left or the right about the vertical axis. There is no quirky weirdness about movements along the vertical axis, so you’re all set with this one.

The only other thing you’ll want to understand well enough that the answer leaps to your mind with the ease of your e-mail password is the names of the control surfaces that control movement in all three axis of flight. Make it easy on yourself and think of it this way. The elevator controls pitch. Elevators move up and down, and pitch moves the airplane up and down. Ergo, elevators control pitch. Elevators are the hinged horizontal control surfaces that are attached to the tail.

Ailerons control roll, or bank. Ailerons are small hinged controls at the back side of the wing, near the tips. When the right one goes up, the left one goes down, and vice versa. Move the ailerons, the airplane rolls. Move them in the opposite direction and the airplane rolls the other way.

The rudder controls yaw. The rudder of an airplane is located pretty much where the rudder of a boat is – mounted vertically at the rear, on the tail.

That’s pretty much it. There are a lot of new terms for student pilots, but the concepts are actually pretty easy. Read the text again if you have to, and you might even grab a model plane to experiment with while you consider the three axis of flight. But if you put even a little effort into it, you should have this down before the sun goes down. It’s pretty easy, really. And you’re pretty sharp. So there you go. Another awesome success story as you work your way up to becoming a pilot. Hang in there, you’re making great progress.

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