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1) Air Foil
2) Forces Acting on an Aircraft
Look at a typical airfoil profile, or airfoil section, and immediately several design characteristics are noted. There is a difference in the curvature of the upper and lower surfaces. The curvature is called camber. The part of the airfoil facing the relative wind is the leading edge and is usually rounded; the opposite part is the trailing edge and is narrow, coming to a point.
A straight line, running between the extreme points of the leadding and trailing edges, is the chord line. A line drawn at equal distance from upper and lower camber at all points of the airfoil section is the mean camber line,
Airfoils have many variations and no one airfoil has been found that satisfies all flight conditions. The weight, speed, and purpose fot which the aircraft is designed dictates the shape of the airfoil. An airfoil that has a concave upper surface will produce the greatest lift; however, this type airfoil also produces a large amount of drag.
AVIATION TECHNICAL ENGLISH
정진화, 김영수, 김봉수, 손일원, 추현희 공저 Michael. Johnson 감수 -오토테크-