The leading edge is the part of the wing that first contacts the air;[1][2] alternatively it is the foremost edge of an airfoil section.[3] The first is an aerodynamic definition, the second a structural one.
As an example of the distinction, during a tailslide, from an aerodynamic point of view, the trailing edge becomes the leading edge and vice versa but from a structural point of view the leading edge remains unchanged.
^Wragg, David W. (1973). A Dictionary of Aviation (first ed.). Osprey. p. 176. ISBN9780850451634.
^Crane, Dale: Dictionary of Aeronautical Terms, third edition, page 305. Aviation Supplies & Academics, 1997. ISBN1-56027-287-2
^Kumar, Bharat (2005). An Illustrated Dictionary of Aviation. New York: McGraw Hill. ISBN0-07-139606-3.