dependent upon the rate at which the angle of bank is established. In other words, rolling into a
turn rapidly requires more rudder than rolling into the same turn slowly. This interrelationship is
absolute and should be thoroughly understood.
Coordinated turn to the left
Slipping turn to the left
Figure 4-8 Coordinated vs Slip Turn
The overlapping function of the controls provides a safety factor in the control of the aircraft. It
is quite possible to fly the plane without the use of one or more controls. For example, suppose
that the elevators failed to operate properly. It is possible to control the position of the nose by
the use of power. As the power is increased, the nose will rise; as the power is decreased, the
nose will drop.
It is also possible to bank the airplane and to turn it without the use of the ailerons. Using only
the rudder, the plane can be turned in any desired direction. This use of the rudder will cause the
aircraft to yaw or skid in the direction in which the rudder is applied. During the yawing motion,
the outside wing moves faster through the air than the inside wing. This increases the lift of the
outside wing, causing it to rise, thus producing a bank in the direction in which the rudder is
applied. A turn can also be accomplished by using only the ailerons. In this instance, the aircraft
will have a tendency to slip before it begins to turn.
The foregoing discussion was given to show the advantage of the overlapping functions of the
controls. It must be emphasized, however, that smooth and balanced flight can only be achieved
through the proper coordination of all controls. Make it easy on yourself; trim your aircraft.
WIND EFFECTS AND CRAB CORRECTIONS
Inasmuch as an aircraft flies in an air mass, any movement of this air mass affects the course of
the aircraft. In other words, the path of the aircraft over the ground will be determined not only
by the direction in which it is headed, but also by the direction and velocity of the air mass
movement. In perfectly still air, for example, the nose of the aircraft points exactly in the same
FUNDAMENTAL FLIGHT CONCEPTS