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Boundary layer suction systems have been considered for a very long time, since they provide significant advantages. However, their main disadvantage, which has never been satisfactorily overcome, is their propensity to clog with dirt and biological matter. The maintenance costs to ensure the system is operational would outweigh the gains in aerodynamic ...


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The decrease in fatigue is not a property that's automatically conferred to the plane by the introduction of wet wing - it's a product of smart design. Usually the decision to use a wet wing is made during the initial design of a plane, and the support structure of the wing is built accordingly, so that it can take the dynamic strains that occur upon ...


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The benefit of tapered wing lies in its proximity to the elliptical lift distribution while retaining much of the structural benefit of a rectangular wing. But we owe this knowledge to a few things: The Kutta-Joukowski Theorem: published in 1906 by Nikolai Y. Joukowski and influenced a great deal by Martin W. Kutta. The Lifting Line Theory: published in ...


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In terms of in-flight behavior, the biggest change between dihedral and polyhedral (or tip dihedral) with the same overall stability is more roll response for a given yaw input -- this occurs because yaw-induced roll is caused by the skid presenting the outside wing at a higher angle of attack than the inside, and this effect is both more pronounced, per ...


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Earlier B-52s did not carry all their fuel in the fuselage. They also carried their fuel in the wings using rubber bladder-type wing tanks. The new B52G “wet wing” was a weight savings measure which also increased the fuel capacity over the bladder-type in-wing tanks. The metal fatigue of the new wing was due to a poor structural design which was supposed ...


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While I don't know of any airplanes that move load in flight for CG purposes, there are definitely airplanes that have various fuel tanks that can be used to trim the airplane during flight. Some of these systems will move the CG aft after takeoff for better performance in cruise, and then move the CG forward before landing for a more stable approach and ...


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Boeing did implement a passive hybrid laminar flow control system using boundary layer suction for the 787-9 on the horizontal and vertical tails. The passive flow control implementation appears to apply US Patent No. 7,866,609B2, which does not require a pump. There are many practical issues that prevent a flow control device and/or method from being used: ...


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Strength, ability to withstand the G forces of turning. Secondly, having a stall Angle of Attack as high as possible. A low aspect ratio wing with a very thick airfoil is a good candidate, such as the ones designed by Hugo Junkers and seen on Fokker planes of 100 years ago. These work very well for slow, turning flight. Another candidate would be the ...


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A random guess without any supporting information. (please edit or delete if this turns out to be inaccurate) I would guess the logistics of manufacturing. It could the space needed for handling the aircraft in and/or out of manufacturing buildings. The B-2 program was wildly expensive due to the large number of new technologies involved. So I guess it was ...


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There are three approaches to this need. First, you could build what amounts to a tandem wing. If you check the CoG location for a Rutan Quickie or its many derivatives, I'm pretty sure you'll find it's between the front (lower) and rear (upper) wings. Likewise, a Flying Flea (aka Pou de Ciel) has the CoG much further aft, relative to the forward/upper ...


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