Aircraft flight controls allow a pilot to safely and efficiently guide his plane to the desired destination. This article describes controls used on a single engine monoplane of conventional design. Other fixed wing aircraft configurations may use different control surfaces but the basic principles remain. The controls for rotory wing aircraft (helicopter or autogyro) are completely different.
NB:Always get professional training before attempting to fly any kind of aircraft.
Table of contents |
2 Main Control Surfaces 3 Secondary Control Surfaces 4 Related topics 5 References 6 External links |
Axes of Motion
An aircraft is free to rotate around three axes which are perpendicular to each other and intersect at the plane's center of gravity (CG). In order to control position and direction a pilot must be able to control rotation about each of them.
- Vertical - The vertical axis passes through the plane from top to bottom. Rotation about this axis is called yaw. Yaw changes the direction the aircraft's nose is pointing, left or right. The primary control of yaw is with the rudder. Ailerons also have a secondary effect on yaw.
- Longitudinal - The longitudinal axis passes through the plane from nose to tail. Rotation about this axis is called bank or roll. Bank changes the orientation of the aircraft's wings with respect to the downward force of gravity. The pilot changes bank angle by increasing the lift on one wing and decreasing it on the other. This differential lift causes bank rotation around the longitudinal axis. The ailerons are the primary control of bank. The rudder also has a secondary effect on bank
- Lateral - The lateral axis passes through the plane from wingtip to wingtip. Rotation about this axis is called pitch. Pitch changes the vertical direction the aircraft's nose is pointing. The elevators are the primary control of pitch.
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Unlike a boat, turning an aircraft is not normally carried out with the rudder. Instead the ailerons are used to bank the aircraft. The forces on the plane cause the aircraft to turn in the same direction as the bank, with a steeper bank causing a faster turn. While this is happening the nose of the aircraft has a tendency to drop, and the aircraft may also yaw, so the nose is not pointing in the direction it is flying. The elevators are used to counteract the first, and the rudder to counteract the second.
Some aircraft configurations have non-standard primary controls. For example instead of elevators at the back of the stabilizers, the entire tailplane may change angle. Some aircraft have a tail in the shape of a V, and the moving parts at the back of those combine the functions of elevators and rudder. Delta wing aircraft may have 'elevons' at the back of the wing, which combine the functions of elevator and ailerons.
Main Control Surfaces
The main control surfaces are attached to the airframe on hinges so they may move and deflect the air stream passing over them. This redirection of the air stream generates an unbalanced force to rotate the plane about the associated axis.Secondary effects of controls
Turning the Aircraft
Alternate main control surfaces
Secondary Control Surfaces
Trimming
Trimming controls allow a pilot to balance the lift and drag being produced by the wings and control surfaces over a wide range of load and airspeed. This reduces the effort required to adjust or maintain a desired flight attitude.
In the simplest cases trimming is done by a mechanical spring which adds appropriate force to the pilot's control.Other Controls
Related topics
References
There are many additional books that deal with flying and flight training. Most will cover this topic.