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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 ...


0

Wing ribs are usually made with the aid of a template or tool. For metal wings, it could be the male and female parts of a mould used in a press. For wooden wings it's a board with blocks of wood that hold all the pieces in place while the glue dries. Either way, a rectangular wing only needs one tool for each rib, while a tapered wing needs a different tool ...


4

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 ...


0

A rectangle gives the maximum area for a given span, and for something like the Flyer, running on 12 hp, they needed all the wing area they could get in the lightest possible package, so rectangular it is. Plus it's the easiest structure to build with minimum weight, since all the joints are simple 90 deg ones and the simple cross braced ladder structure is ...


0

The rectangular "Hershey Bar" is a safe reliable, and yes, easier to build design. But if you look more carefully at the Wright Flyer wings, you can see they were already rounding off the trailing edges to decrease drag. Tapering to a point serves the same function, and also enables one to build a bit more lightly due to reduced torque stress from the end ...


3

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 ...


4

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 ...


0

You could make either one work, especially for a "straight through" tunnel. The key is to smooth out the turbulence after the fans to as straight and undisturbed a line as possible. Smoke trails help check your wind stream before the model is put into place for testing, and remain valuable to see changes in the wind flow pattern as it passes over the ...


4

The increase in the lift curve slope at low angle of attack is quite normal. At 10° you see the effect of vortex lift kicking in. Yes, that is specific to delta wings. Attached and vortex lift over angle of attack (picture source). This is taken from the excellent Cambridge Core article on vortex lift and these particular diagrams are from E.C. Polhamus: A ...


9

Quoting the F/A-18A,B,C,D Flight Manual A1-F18AC-NFM-000, I-2-42 2.8.2.8 Control Augmentation System (CAS) [...] The lateral control system uses ailerons, differential trailing edge flaps, differential leading edge flaps, differential stabilator, and rudders to achieve the desired roll characteristics. Scheduled air data roll rate feedback is used ...


1

First, I would like to point out the question was about limit load on airplane wings, which is different that load limits for the entire aircraft. Therefore, this sounds like an airframe question, not propulsion. Let's look from the wing frame of reference: it does not care if aircraft is going level, up, down, sideways, or upside down. All it cares is ...


0

Why worry about any of this? In a steep turn, the best place for the underwing stores is evenly distributed about the centerline, same as in wings-level flight. Are you trying to address the situation where some stores are dropped and others are not? Aileron trim should be be sufficient to address this issue.


1

It's a mixture of both: You add the projected area of both wings, measured separately, without overlap. The effective (wetted) area is used for friction drag calculations only.


8

Five short, generic reasons (i.e., not specific to the Weedhopper): Fatigue reduction: some highly stressed parts of the airframe (particularly mainspars and engine mounts) are susceptible to fatigue failure from cyclic loading. The key word here is 'cyclic'; a spar which is subjected to loads between (say) -5g/+5g will fail faster than one which is ...


40

You can get negative load factors (g forces) in different ways than just flying upside down: Change in pitch: When you push on the control column, the pitch will start to decrease. Depending on how fast you do this, the load factor can even become negative from this. Some aircraft do this intentionally to reduce the g force to exactly zero: (image source: ...


28

The Auxiliary Power Unit (APU) exhaust This is answered by the following image (taken from this question, color markings are unrelated to this answer): The item 72 is what you are looking for and it is labelled "APU exhaust". The black residue is soot from incompletely burned fuel. The Eurofighter Typhoon can use its APU to start the main engine or to ...


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