High altitude flight
At higher altitudes the air speed indicator will indicate values lower than
the true airspeed due to the lower air density. This does not influence
loads on the structure, but it does mean that the colour markings on the
air speed indicator are not correct at high density altitude. As flutter
depends upon true airspeed, the maximum allowable airspeed must be
reduced at high altitudes. Figure 4.5-3 gives the V
NE
as a function of
altitude for both the 15 m and 18 m configurations.
Figure 4.5-3