Page 497 - PPL-engelsk 2025

Principles of flight

5.8 Limitations

5.8.1 Airspeed indicator limitations

To protect against overload, there are certain speed limits to operate within.

To assist the pilot, the airspeed indicator is provided with color markings. Each

color represents an operating range.

The transition between the colors shows the aircraft's different limitations.

White arc: Flaps operational.

Here are two limits:

- Vs0 = Lower limit for stall speed with full flaps

and engine on idle.

- Vfe = Upper limit is the highest speed for fully extended flaps.

Green arc: Normal operating range

- Vs1 = Lower limit for stall speed for the aircraft at full weight, with the
engine at idle and flaps and landing gear up.

- Vno = Upper limit is the maximum cruising speed, the highest airspeed

indicator reading at which the aircraft will not be damaged in moderate

turbulence.

Yellow arc: Caution area – full rudder deflection may not be used with caution

in turbulent weather. In severe turbulence, the aircraft can be damaged in this

speed range.

- In severe turbulence the speed must be reduced, and the controls may

be handled with care

- Vne = Upper limit of operation.

The red line (Vne) must not be exceeded

under any circumstances.

Flight Theory PPL(A)(UL)/LAPL Henning Andersen, Midtjysk Flyveskole© 2025 497