Editing Lift-induced drag (section)

{{Short description|Type of aerodynamic resistance against the motion of a wing or other airfoil}}
'''Lift-induced drag''', '''induced drag''', '''vortex drag''', or sometimes '''drag due to lift,''' in [[aerodynamics]], is an [[aerodynamic drag]] force that occurs whenever a moving object redirects the [[airflow]] coming at it. This drag force occurs in airplanes due to [[wing]]s or a [[lifting body]] redirecting air to cause [[lift (force)|lift]] and also in cars with [[airfoil]] wings that redirect air to cause a [[downforce]]. It is symbolized as <math display="inline">D_\text{i}</math>, and the '''''lift-induced drag coefficient''''' as <math display="inline">C_{D,i}</math>.

For a constant amount of lift, induced drag can be reduced by increasing airspeed. A counter-intuitive effect of this is that, up to the speed-for-minimum-drag, aircraft need less power to fly faster.<ref name="Fehrm">{{cite news |url= https://leehamnews.com/2017/11/03/bjorns-corner-aircraft-drag-reduction-part-3/ |title= Bjorn's Corner: Aircraft drag reduction, Part 3 |author= Bjorn Fehrm |date= Nov 3, 2017 |work=Leeham}}</ref> Induced drag is also reduced when the [[wingspan]] is higher,<ref name="Illsley"/> or for wings with [[wingtip device]]s.