Aircraft use various aerodynamic surfaces to manage movement in three dimensions: roll, yaw, and pitch. These surfaces manipulate airflow, generating forces that allow pilots to direct flight paths. Among these, the elevator controls a specific aspect of the aircraft’s attitude.
What an Elevator Is
An elevator is a movable control surface located at the rear of an aircraft. It is typically found on the trailing edge of the horizontal stabilizer, which is the small wing-like structure at the tail of the plane. The elevator is a hinged component, attached to the horizontal stabilizer by hinges that permit its rotation. While the horizontal stabilizer itself provides stability, the movable elevator provides the means for active control. This arrangement is present on most conventional fixed-wing aircraft, from small general aviation planes to large commercial airliners.
How an Elevator Controls Pitch
The elevator’s primary function is to control the aircraft’s pitch, the nose-up or nose-down movement around its lateral axis. Pilots achieve this control by manipulating the aircraft’s control stick or yoke in the cockpit. Pushing the control stick forward or pulling it backward directly translates into a corresponding movement of the elevator.
When the pilot pulls the control stick back, the elevators on the tail move upward. This upward deflection changes the angle at which air flows over the horizontal stabilizer, effectively increasing the downward aerodynamic force on the tail. Conversely, pushing the control stick forward causes the elevators to deflect downward, which reduces the downward force or even creates an upward force on the tail. These changes in force on the tail cause the aircraft to rotate around its center of gravity. A downward force on the tail pitches the nose upward, while an upward force on the tail pitches the nose downward.
Importance for Flight Control
The elevator’s ability to control pitch is fundamental to nearly every phase of flight. During takeoff, pilots pull back on the controls to raise the nose for lift-off. For landing, the elevator is used to “flare” the aircraft, gently raising the nose and reducing the descent rate just before touchdown for a smooth touchdown. In level flight, the elevator helps maintain altitude and attitude.
It is also indispensable for executing climbs and descents. To climb, the elevator is used to pitch the nose up, increasing the aircraft’s angle of attack and allowing it to gain altitude. Conversely, to descend, the elevator pitches the nose down, enabling the aircraft to lose altitude in a controlled manner. Without a functioning elevator, precise control over the aircraft’s vertical trajectory and overall stability would be impossible.