Page 769 - PPL-engelsk 2025

Aircraft general knowledge

Here tou see a schematic

diagram showing the

function of the air speed

indicator.

The (total) dynamic pressure comes in via the pitot tube.

The more pressure, the more the spiral tube will expand. This causes, via rods

and the triangle, a movement of the pointer.

In the instrument housing itself there is static pressure, so the airspeed indicator

shows the difference between total pressure and static pressure – namely the

dynamic pressure.

8.12.5.1 The airspeed indicator

Here you can see the airspeed indicator

pointer itself. As can be seen, there are color

divisions on the speedometer.

The white area is the flap area.

The lowest speed is the stall speed with full
weight and with the engine idling. The highest

speed is the max. speed with flaps.

The green arc is the normal area.

The lowest value is the stall speed at full weight with the engine idling, and

without using flaps. The dividing line between the green and yellow areas is
called VNO.

Yellow area. Caution must be exercised.

Red line indicates the maximum permitted speed VNE.

Flyveteori PPL(A)(UL)/LAPL Henning Andersen, Midtjysk Flyveskole© 2025 769