AAE 334 EXAM 2 QUESTIONS ANSWERED CORRECTLY LATEST UPDATE 2026

AAE 334 EXAM 2 QUESTIONS ANSWERED CORRECTLY LATEST UPDATE 2026 what causes induced drag - Answers There is always trailing vorticity in the wake for a finite wing with non zero lift. This vorticity causes downwash. Downwash effects the freestream direction experienced by the wing, and rotates the lift vector slightly backwards. The component of lift that resists forward motion is induced drag Why does a starting vortex appear - Answers The circulation around a material curve is constant in inviscid flow. Since the circulation is initially zero, the circulation around the airfoil must be balanced with a strating vortex of opposite sign. Induced drag can be explained by a-rotation of lift vector through induced angle of sttack b-viscous friction c- loss of flow energy to the wingtip vorticies - Answers a&c In a super sonic wind tunnel, which of the following is true - Answers ToTe downwash - Answers velocity induced on the airfoil by the trailing vorticity in the wake. it changes the angle of attack seen by the airfoil A vortext cannot end in the fluid it must - Answers go to infinity terminate on a boundary close on itself Horseshoe vortex model load distribution - Answers constant More realistic load distribution - Answers its a curve Weakness of Prandtly Lifting line - Answers flaps, youre treating syestem as flat sheet induced drag alpha eff - Answers alphaeff=alpha-alphai Elliptic lift distribution gives - Answers uniform downwash and uniform induced angle of attack Relationship between AR and CDI - Answers AR reduces CDI Elliptic distribution loading is ideal bc - Answers it reduces the drag for that aspect ratio shape Steps to prandtl - Answers substitute series 2. combine terms. 3. enforce at a number of points bc n unknowns and n equations Elliptic circulation distribution ____ for a fixed wingspace - Answers minimizes iduced drag Rectangle wing oswald efficiency factor - Answers not a huge change, but even a few percent is significant Ways to get ellipitc load disitribution - Answers elliptic chord, geometric twist (alpha), aerodynamici twist(Elliptic zero alpha), combination Taper wings - Answers compromise between elliptic loading and wide AR There is an ideal taper ratio that___ - Answers minimizes the induced drag factor absolute angle of attack - Answers additional absolute angle of attack + basic angle of attack additional angle of attack - Answers constant for whole wing, zero lift angle for whole wing basic absolute angle of attack - Answers accounts for twist, inddpenet of angle of attack Wash Out - Answers Used to avoid tip stall, having less circulation towards the tip of aircraft Wing tip devices - Answers redistribute vorticity at tip to reduce induced drag winglets - Answers result in ground clearance problems, help with lateral stability, Benefits fo Wing Sweep - Answers increase critical mach, reduce lift slop, reduce lift coeff, reduce minimum cp Effect of Wing sweep - Answers Bound vortex from one wing causes downwash on opposite wing -increased tip loading can cause tip stall -forward c.o.p. hinders stability -3d boundary layer -unstable at low RE Mitigating tip stall - Answers wash out -vortex generators -boundary layer fences Forward Swept wings - Answers bound vortex from one wing causes upwash on other -root stalls first -unstable in pitch Delta wigns - Answers good for supersonic flight leading edge inside mach cone cruise supersonically for fuel effiency fly at low speed for takeoffy and landing Span wise pressure coefficient for delta wing - Answers leading edge vorticies produce suction and