How do planes turn with a wing almost perpendicular to the ground (and avoid throwing all its passengers to one side)


How do planes turn with a wing almost perpendicular to the ground (and avoid throwing all its passengers to one side)

In: Physics

Centrifugal force.

When you are in a car and the car takes a turn at speed, you feel like you’re being squeezed against the outside of the turn. This is because your body desires to follow the laws of physics and continue in it’s current trajectory, Forward.

The same happens with an airplane, the passengers are going forward, when the plane turns perpendicular, it’s actually going slightly ‘up’ (in respect to the plane, not the ground), this keeps force on your feet (or butt, you should be seated), because your body wants to keep going forward instead of turning with the plane, this keeps you glued in place so to speak.

They don’t really ever make significant turns left and right without banking. The act of banking is why we perceive a turning plane pulling you downward into your seat, and doesn’t throw you to the side. Planes use three types of control services. Ailerons on the end of each wing roll the plane, the elevators (the horizontal part of the tail) controls pitch (pointing the noise up and down) and the rudder (vertical tail plane) control the nose left and right (also called yaw). Without getting too complicated the rudder has a bit of an issue, it is the only control that is asymmetrical, because there isn’t another vertical tail plane sticking out the bottom of the tail. That means when the rudder turns the plane it will also cause the plane to roll. Say we want to turn left, the flap in the vertical tail piece moves left and pushes the tail right and turns the nose if the plane left. Great. But unfortunately with no other inputs the plane is starting to roll to the right. Because they control surface is up above the planes center off mass in also induced roll. Banking away from a turn would be very unpleasant as it would feel like the plane is diving around the bend. So pilots have to counteract this and roll into the turn.

The roll axis on an airplane (and boat, and roller coaster for that matter) is used to replace lateral G forces (what slings you side to side and causes cars to skid out) with Positive G forces (getting pressed down into your seat). The pilot rolls the plane (or the track rolls the roller coaster) to an angle where your body is standing or sitting vertically on the curve, not perpendicular to it.