Controllable slope soaring
Encyclopedia
Slope
In mathematics, the slope or gradient of a line describes its steepness, incline, or grade. A higher slope value indicates a steeper incline....
is made to follow the airplane in gliding flight, both sustaining and controlling the airplane's trajectory
Trajectory
A trajectory is the path that a moving object follows through space as a function of time. The object might be a projectile or a satellite, for example. It thus includes the meaning of orbit—the path of a planet, an asteroid or a comet as it travels around a central mass...
by modifying the wind
Wind
Wind is the flow of gases on a large scale. On Earth, wind consists of the bulk movement of air. In outer space, solar wind is the movement of gases or charged particles from the sun through space, while planetary wind is the outgassing of light chemical elements from a planet's atmosphere into space...
in the vicinity of the airplane. A controllable slope is any object which can be used to affect the air under the airplane: a piece of cardboard
Paperboard
Paperboard is a thick paper based material. While there is no rigid differentiation between paper and paperboard, paperboard is generally thicker than paper. According to ISO standards, paperboard is a paper with a basis weight above 224 g/m2, but there are exceptions. Paperboard can be single...
, your hands or even your head
Head
In anatomy, the head of an animal is the rostral part that usually comprises the brain, eyes, ears, nose and mouth . Some very simple animals may not have a head, but many bilaterally symmetric forms do....
. The controllable slope is usually manipulated by a person following the glider
Glider aircraft
Glider aircraft are heavier-than-air craft that are supported in flight by the dynamic reaction of the air against their lifting surfaces, and whose free flight does not depend on an engine. Mostly these types of aircraft are intended for routine operation without engines, though engine failure can...
in flight
Flight
Flight is the process by which an object moves either through an atmosphere or beyond it by generating lift or propulsive thrust, or aerostatically using buoyancy, or by simple ballistic movement....
(please see photo at right). Controllable-slope soaring allows a glider to achieve sustained flight without the need for an onboard aircraft engine
Aircraft engine
An aircraft engine is the component of the propulsion system for an aircraft that generates mechanical power. Aircraft engines are almost always either lightweight piston engines or gas turbines...
or onboard flight control system.
See also
- Gliding flight
- Orographic liftOrographic liftOrographic lift occurs when an air mass is forced from a low elevation to a higher elevation as it moves over rising terrain. As the air mass gains altitude it quickly cools down adiabatically, which can raise the relative humidity to 100% and create clouds and, under the right conditions,...
- Soaring
- ridge liftRidge liftRidge lift is created when a wind strikes an obstacle, usually a mountain ridge or cliff, that is large and steep enough to deflect the wind upward....
- walkalong gliderWalkalong gliderA walkalong glider is a lightweight, slow flying model aircraft designed to be kept aloft by slope soaring in the lift generated by a paddle held by the pilot who walks along with the glider as it flies. Hands or even the forehead can also be used to do this...
- Human-powered aircraftHuman-powered aircraftA human-powered aircraft is an aircraft powered by direct human energy and the force of gravity; the thrust provided by the human may be the only source; however, a hang glider that is partially powered by pilot power is a human-powered aircraft where the flight path can be enhanced more than if...