Page 515 - PPL-engelsk 2025
P. 515
Principles of flight
5.10.4 Turn
When we fly, we have to make a turn at some point.
A turn is done using the ailerons, possibly with a little coordination by using the
rudder, so that the flight is coordinated.
When the plane is banked, the lift vector is tilted.
The weight of the plane is still acting downwards.
The lift is now greater than the weight, and a vertical part corresponds to the
weight.
5.10.4.1 Centripetal force
When you turn, the lift vector is tilted
(blue arrow).
Now the lift is greater than the weight
(red arrow).
A vertical part of the lift must correspond
to the weight (dashed red arrow).
The green arrow symbolizes the force required to turn the plane. We call this
force the centripetal force.
At the bottom of the picture, you can see a yellow arrow, which symbolizes
centrifugal force.
The more the bank increases, the more lift is required.
To get this lift we need to increase the angle of attack by pulling back the steering
wheel.
This creates more resistance, and extra engine power is needed to keep the
plane moving when the bank becomes more than about 30°.
Flight Theory PPL(A)(UL)/LAPL Henning Andersen, Midtjysk Flyveskole© 2025 515
