Here’s a look at the three principal airplane axes, how the plane moves around them, and how a pilot controls everything.
One of the unique things about learning to fly an aircraft is that it moves in three dimensions.
To understand how this works, we describe the airplane moving around three axes—an axis for each type of movement.
The Three Axes of Flight, Flight Controls, and Pilot Inputs
An axis of flight is an imaginary line drawn through the aircraft. All axes meet at a central point—the center of gravity, or CG.
Each axis represents a sort of pivot point. The aircraft moves around that axis thanks to a specific flight control, and each movement has its own name.
Since the aircraft moves in three dimensions, there are three different axes controlled by three different flight controls and movements.
- The aircraft pitches around the lateral axis with the elevator.
- The aircraft rolls around the longitudinal axis with the ailerons.
- The aircraft yaws around the vertical axis with the rudder.
Lateral Axis and Pitch
That lateral axis of the airplane runs from wingtip to wingtip.
When a plane moves around the lateral axis, it is called pitch. Pitch is controlled by the elevator.
The elevator is mounted to the horizontal stabilizer on the empennage of an airplane. It’s controlled by the pilot’s control yoke or stick.
Pushing the stick forward moves the elevator downward, which in turn pitches the nose of the plane down.
Pulling the stick back (pull up!) moves the elevator upward, which moves the nose of the plane up in relation to the horizon.
Longitudinal Axis and Roll
The airplane’s longitudinal axis runs from the tip of the nose to the tip of the tail.
An airplane rolls around its longitudinal axis. Roll is controlled with the ailerons on the wingtips.
The ailerons are also connected to the pilot’s control yoke or stick.
Moving the stick from side to side moves the ailerons on the wings. When the pilot moves the stick left, the left wing’s aileron goes up, and the right wing’s goes down. Moving the stick to the right does the opposite.
The ailerons work by adding and subtracting the lift over the outer wings.
The upward aileron subtracts lift, and the downward one adds it.
So, when the pilot moves the stick left, the left wing makes less lift than the right wing, and the plane rolls around the longitudinal axis until the stick is centered again.
Vertical Axis and Yaw
The vertical axis of the airplane runs up and down through the CG.
The plane yaws around the vertical axis, and the rudder controls that.
Yaw is probably the hardest motion to visualize because planes are seldom seen yawing. Yaw is combined with other forces to coordinate turns.
In other words, the pilot usually uses the rudder in combination with the ailerons.
Yaw is controlled with the rudder, which is mounted on the vertical stabilizer on the empennage. The rudder is moved by pressing the pedals on the floor.
Push the left pedal, and the rudder deflects left. That, in turn, moves the nose of the aircraft to the left.
Putting It All Together
Of course, a pilot likely isn’t thinking about all that in flight.
Flying a plane is like riding a bike—once you learn what the controls do and what to do with them, you just do it automatically.
But getting to that point and knowing when to do what requires studying how the plane works and the aerodynamics behind it. And that’s where the principle airplane axes come in.
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Brian is an experienced digital marketer who joined Thrust Flight in 2022 as the Chief Marketing Officer. He discovered a passion for aviation at 10 when he went for his first flight in a Piper Cherokee and enjoys helping others discover a career path as a professional pilot. He is an experienced marketing consultant helping brands with a variety of marketing initiatives. Brian received a bachelor’s degree in Communications from Brigham Young University.