One of the objectives of the glider pilot is to loose as little height as possible while covering the maximum distance.

Aerodynamics specialists therefore endeavour to design optimal fuselage and wing shapes to achieve the best possible gliding efficiency. This gliding efficiency is expressed as the covered distance / lost height ratio. It is also the lift -to-drag ratio.

Wing profiles are defined by computer programmes (computation codes) solving the fluid mechanic equations. These codes are used to predict the polar of the profiles (lift and drag variation versus angle of attack ).