Speed To Fly
Speed to fly is a principle used by soaring pilots when flying between sources of lift, usually thermals, ridge lift and wave. The aim is to maximize the average cross-country speed by optimizing the airspeed in both rising and sinking air. The optimal airspeed is independent of the wind speed, because the fastest average speed achievable through the airmass corresponds to the fastest achievable average groundspeed. The speed to fly is the optimum speed through sinking or rising air mass to achieve either the furthest glide, or fastest average cross-country speed. Most speed to fly setups use units of either airspeed in kilometers per hour (km/h) and climb rate in meters per second (m/s), or airspeed in knots (kn) and climb rate in feet per minute (ft/min). History The idea is usually attributed to Paul MacCready, although an early version of the theory was first described by Wolfgang Späte in 1938. However Späte may not have considered sinking air between thermals, and the ...
[...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  

MacCready Ring And Variometer
MacCready is a Scottish version of the Gaelic surname McCready, McCreadie or McCredie. Notable people with the surname include: * Derek MacCready (born 1967), Canadian football league player * Paul MacCready (born 1925), American aerospace engineer and champion glider pilot ** 24643 MacCready, a Mars-crossing asteroid, named after Paul MacCready See also * * Gwyn Cready Gwyn Cready (born January 17, 1962) is an American author of romance novels. Biography Personal life Cready was born in Pittsburgh, Pennsylvania. She attended Mt. Lebanon High School, where she became close friends with novelist Teri Coyne and ...

Polar Curve (aerodynamics)
The drag curve or drag polar is the relationship between the drag on an aircraft and other variables, such as lift, the coefficient of lift, angle-of-attack or speed. It may be described by an equation or displayed as a graph (sometimes called a "polar plot"). Drag may be expressed as actual drag or the coefficient of drag. Drag curves are closely related to other curves which do not show drag, such as the power required/speed curve, or the sink rate/speed curve. The drag curve The significant aerodynamic properties of aircraft wings are summarised by two dimensionless quantities, the lift and drag coefficients and . Like other such aerodynamic quantities, they are functions only of the angle of attack , the Reynolds number and the Mach number . and can be plotted against , or can be plotted against each other. The lift and the drag forces, and , are scaled by the same factor to get and , so = . and are at right angles, with parallel to the free stream velo ...
[...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]