Pitch Control - Flight Controls - Airframes & Aircraft Systems #26

Summary

This lesson covers the primary flight controls used to manage an aircraft’s pitch, focusing on elevators and moving tailplanes. Elevators, typically mounted on the tailplane, control the aircraft's pitch around the lateral axis. Pilots adjust the yoke or control column to move the elevators, either pulling it towards them to pitch the nose up or pushing it forward to pitch the nose down. In some aircraft, the entire tailplane can be adjusted to control pitch instead of individual elevators. This movement of the stabilizer alters the angle of attack, thereby controlling the aircraft’s pitch. By the end of the lesson, students will understand how pitch control is achieved using these systems.

Takeaways

• 😀 Longitudinal control of the aircraft is achieved using elevators or a moving tailplane.
• 😀 Elevators are flap-type control surfaces located on the trailing edge of the tailplane or stabilizer.
• 😀 The primary function of elevators is to control the aircraft's pitch about the lateral axis.
• 😀 Elevators must provide adequate balance for the aircraft at all speed ranges and center of gravity positions.
• 😀 The pilot uses a yoke or control column to control the elevators in a fore-and-aft direction.
• 😀 Pulling the yoke towards the pilot causes the elevators to move up, generating an aerodynamic downforce on the tail, which pitches the aircraft's nose up.
• 😀 Pushing the yoke away from the pilot causes the elevators to move down, producing an upforce on the tail and pitching the aircraft's nose down.
• 😀 Varying the angle of attack of an aerofoil, such as the tailplane, can also control pitch in some aircraft.
• 😀 A moving tailplane (instead of elevators) adjusts the angle of attack to vary the aircraft's lift for pitch control.
• 😀 If the yoke is pushed forward, the leading edge of the stabilizer moves up and the trailing edge down, increasing lift and pitching the nose down.
• 😀 Pulling the yoke back rotates the stabilizer in the opposite direction, decreasing lift and pitching the nose up.

Q & A

What is the primary function of the elevators in an aircraft?

The elevators control the pitch of the aircraft about its lateral axis. They adjust the aircraft's nose position, either pitching it up or down.

Where are the elevators typically located on an aircraft?

Elevators are usually fitted to the trailing edge of the tailplane or stabilizer of the aircraft.

How do pilots control the elevators in the cockpit?

Pilots control the elevators using a yoke or control column, which moves in a fore and aft direction to adjust the aircraft's pitch.

What happens when the pilot pulls the yoke towards himself?

When the pilot pulls the yoke towards himself, the elevator moves up, generating a downward aerodynamic force on the tail and pitching the aircraft's nose up.

What effect does pushing the yoke forward have on the aircraft?

Pushing the yoke forward causes the elevator to move down, producing an upward force on the tail and pitching the nose of the aircraft down.

What is the difference between using elevators and a moving tailplane for pitch control?

Elevators are individual control surfaces located on the tailplane, whereas a moving tailplane adjusts its entire angle of attack to control pitch.

How does the movement of the yoke affect the angle of the tailplane?

When the yoke is pushed forward, the leading edge of the tailplane moves up and the trailing edge down, increasing lift and pitching the nose down. Pulling the yoke back moves the tailplane in the opposite direction and pitches the nose up.

Why is the control of pitch essential during flight?

The control of pitch is essential for maintaining the aircraft's stability and attitude, ensuring that it maintains the desired flight path and does not climb or descend unintentionally.

How does varying the incidence of an aerofoil affect its performance?

Varying the incidence (angle of attack) of an aerofoil changes the lift it generates. This is used in some aircraft to control pitch, either by using elevators or by adjusting the entire tailplane's angle.

What ensures that the aircraft remains balanced and controllable during flight?

Adequate control surfaces, like elevators or a moving tailplane, are essential to balance the aircraft throughout its speed range and at all permitted center of gravity positions, ensuring stable and controlled flight.