of a gliding aircraft. Glide angle is only determined by the lift/drag ratio. Increased weight will require an increased airspeed to maintain the optimum glide angle, so a heavier gliding aircraft will have reduced endurance, because it is descending along the optimum glide path at a faster rate. See also Drag coefficient Lift coefficient Angle of attack Lift (force) Lifting-line theory External links Glider Performance Airspeeds An animated explanation of the basic polar curve, with modifications for sinking or rising air and for head- or tailwinds. References Aerodynamics Aircraft performance Airspeed Drag (physics) Gliding technology de:Polardiagramm (Strömungslehre)