Search results
Results from the WOW.Com Content Network
In aerodynamics, the lift-to-drag ratio (or L/D ratio) is the lift generated by an aerodynamic body such as an aerofoil or aircraft, divided by the aerodynamic drag caused by moving through air. It describes the aerodynamic efficiency under given flight conditions. The L/D ratio for any given body will vary according to these flight conditions.
The ratio of the distance forwards to downwards is called the glide ratio. The glide ratio (E) is numerically equal to the lift-to-drag ratio under these conditions; but is not necessarily equal during other manoeuvres, especially if speed is not constant. A glider's glide ratio varies with airspeed, but there is a maximum value which is ...
One of the measures of a glider's performance is the distance that it can fly for each meter it descends, known as its glide ratio. Glide ratio is dependent on an aircraft's class, and can typically range from 44:1 (for modern designs in the Standard Class) up to 70:1 (for the largest aircraft).
Two of the key measures of a glider’s performance are its minimum sink rate and its best glide ratio, also known as the best "glide angle". These occur at different speeds. Knowing these speeds is important for efficient cross-country flying. In still air the polar curve shows that flying at the minimum sink speed enables the pilot to stay ...
Glide slope is the distance traveled for each unit of height lost. In a steady wings-level glide with no wind, glide slope is the same as the lift/drag ratio (L/D) of the glider, called "L-over-D". Reducing lift from the wings and/or increasing drag will reduce the L/D allowing the glider to descend at a steeper angle with no increase in airspeed.
One measure of performance is the glide ratio. For example, a ratio of 12:1 means that in smooth air a glider can travel forward 12 metres while only losing 1 metre of altitude. Some performance figures as of 2006: Topless gliders (no kingpost): glide ratio ~17:1, speed range ~30–145 km/h (19–90 mph), best glide at 45–60 km/h (28–37 mph)
The glide ratio of paragliders ranges from 9.3 for recreational wings to about 11.3 for modern competition models, [17] reaching in some cases up to 13. [18] For comparison, a typical skydiving parachute will achieve about 3:1 glide. A hang glider ranges from 9.5 for recreational wings to about 16.5 for modern competition models.
The glide ratios of older wingsuits made in the 1990s through the early 2010s were closer to 2:1. [8] It was possible for expert flyers to achieve a 3:1 ratio [8] but this was very difficult. However, advancements in modern wingsuits allow flyers to achieve a 3:1 ratio much more easily, allowing for higher speeds. [9]