stunt planes) and most modernįighter jets, they don't rely at all on wing shape for lift. This answer gives you the details.įor example aerobatic airplanes (i.e. The main advantage is less in inverted flight per se but in the transition between upright and inverted flight. It is much easier to fly rolls with an uncambered wing. With separated flow, the details of the wing's contour don't count anymore, so camber is again not needed in fighter wings when high lift is required.Īerobatic planes do away with camber completely, and for a different reason. When those fighter wings need to produce lots of lift (which happens either at take-off and landing, or in maneuvering around Mach 0.7), they rely on vortex lift which is caused by flow separation at the leading edge of a swept wing. Fighter wings have very little relative thickness and little camber in order to reduce wave drag. Airfoil camber (that is the proper name you were looking for) helps at subsonic speed to make lift creation more efficient, but is a source of drag ( wave drag) at supersonic speed. Again, read įighter jets are designed to fly at supersonic speed. What is wrong is the typical explanation, which is still being taught to kids. Wings on aerobatic airplanes are symmetrical because they typically fly inverted just as well as upright. The shape is just an optimization for typical flight. Wings lift because they push the air down, not because they are shaped a particular way, but because they fly at an angle-of-attack (AOA). The result is a vortex in which air is pushed DOWN, and that makes the lift. So in order to get faster flow over the top (for lift), there must be a longer curve over the top. The "equal-time fallacy" says when two molecules of air get separated at the leading edge of a wing, they must come together at the trailing edge. Look, here is the best explanation I've seen about how wings work and airplanes fly: The "equal-time fallacy" is alive and kicking, as shown in your question and the other answers. It would be logical to make use of this feature in fighter jets and aerobatic airplanes to generate larger lift with less thrust and less fuel consumption. Thus, increases lift in addition to the main lift generated by the angle of attack and incidence angle. What is the trade-off here? A curved wing creates lower resistance on the upside and therefore faster air speed and lower air pressure (Bernoulli's principle) upside. Why not this additional feature of upside curved wing shape is not present in this kind of airplanes? Is there any particular reason(s)? Therefore, their flat evenly shaped wings do not support additionally to the angle of attack and incidence angle the lift of the plane. instead of being usually in other airplanes, curved upside and flat downside). Their wings are evenly shaped flat upside and downside (i.e. stunt planes) and most modern fighter jets, they don't rely at all on wing shape for lift. I am not referring to the angle of attack adjusted by the pilot during flight or to any preinstalled by the manufacturer angle of incidence on the wings to support lift but solely to the shape of the wings. This is anti-economic and puts the airplane under unnecessary mechanical stress. According to Bernoulli's principle and for a given angle of attack would that not lower the lift force of the airplane and increase its drag and therefore increasing its demand in thrust and fuel consumption?
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