The pilot’s controls

Since the very earliest days, the three primary control actions available to the pilot of a conventional aircraft have been those of pitch, roll, and yaw, as defined in Fig. 10.1. On most military interceptor aircraft, the controls are operated by the same type of control stick or joystick as used on early aircraft. On most other aircraft, some form of handlebars or spectacle grip is provided, either protruding from the instrument panel as in Fig. 10.2, or mounted on a movable control column.

With the introduction of completely electronically operated fly-by-wire sys­tems (described later), where the control column provides no direct mechanical operation of the control surfaces, a new form of control called a sidestick has

Fig. 10.2 Controls and instruments on a well-equipped light aircraft (actually a simulator)

been introduced, as seen in Fig. 10.3. This is a miniature form of joystick designed for one-handed operation, and mounted at the side of the pilot’s seat. The use of a sidestick produces a less cluttered flight deck, as shown in the photograph.

In conventionally controlled aircraft, pulling back on the stick or handlebars produces nose-up pitching action. Note, however, that in a weight-control hang-glider or microlight (Fig. 11.10), the control action is reversed; the pilot pulls on the control bar to transfer his weight forwards, tending to produce a nose-down effect. Pilots of conventional aircraft need to be very careful when converting to microlights, and vice-versa.

Turning the handlebars on a conventional aircraft clockwise, or pushing the stick to the right, produces, as its primary effect, a clockwise roll (and a

Fig. 10.3 Airbus A320 flight deck

The sidestick and display screen produce a much less cluttered arrangement than on older airliners

(Photo courtesy of British Aerospace)

consequential tendency to turn to the right). In this book, by left and right we mean pilot’s left and right.

Yaw control is provided by foot-operated pedals. Pushing on the pedal bar with the right foot causes the aircraft to yaw to the pilot’s right. Most people find this pedal action natural, which is curious, because unlike the other con­trols, the pedals work in the opposite sense to the turning direction required. On a bicycle, pushing the right handlebar would turn the bicycle left.

Note, that the amount of rotation of the handlebars affects the rate of roll, rather than the angle to which the aircraft rolls.