Search results
Results from the WOW.Com Content Network
This characteristic is important in determining whether an aircraft pilot will be able to control the aircraft in the pitching plane without requiring excessive attention or excessive strength. [ 1 ] The longitudinal stability of an aircraft, also called pitch stability, [ 2 ] refers to the aircraft's stability in its plane of symmetry [ 2 ...
Although usually stable in a normal aircraft, the motion may be so slightly damped that the effect is very unpleasant and undesirable. In swept-back wing aircraft, the Dutch roll is solved by installing a yaw damper , in effect a special-purpose automatic pilot that damps out any yawing oscillation by applying rudder corrections.
A Boeing 737 uses an adjustable stabilizer, moved by a jackscrew, to provide the required pitch trim forces. Generic stabilizer illustrated. A horizontal stabilizer is used to maintain the aircraft in longitudinal balance, or trim: [3] it exerts a vertical force at a distance so the summation of pitch moments about the center of gravity is zero. [4]
Longitudinal stability refers to the stability of an aircraft in pitch. For a stable aircraft, if the aircraft pitches up, the wings and tail create a pitch-down moment which tends to restore the aircraft to its original attitude. For an unstable aircraft, a disturbance in pitch will lead to an increasing pitching moment.
[citation needed] A positively stable aircraft will also resist any bank movement. A Cessna 152 is an example of a stable aircraft. Similarly, an aircraft with neutral stability will not return to its original attitude without control input, but will continue to roll or pitch at a steady (neither increasing nor decreasing) rate.
The longitudinal modes of a statically stable airplane following a disturbance were shown to consist of a long-period oscillation called the phugoid oscillation, usually with a period in seconds about one-quarter of the airspeed in miles per hour and a short-period oscillation with a period of only a few seconds. The lateral motion had three ...
A number of factors affect this characteristic. [24] For example, seven years after the Wrights' first flight, the ASL Valkyrie adopted the canard position in order to make the aeroplane stable and safe. For most airfoils, lift slope decreases at high lift coefficients. Therefore, the most common way in which pitch stability can be achieved is ...
X stability axis is aligned into the direction of the oncoming air in steady flight. (It is projected into the plane made by the X and Z body axes if there is sideslip). Y stability axis is the same as the Y body-fixed axis. Z stability axis is perpendicular to the plane made by the X stability axis and the Y body axis.