# Tag Info

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The small wings make it fly like a brick. Without the wings it would fly like a stone. Seriously, you are taking the expression too literally. The Space Shuttle is landing like a glider plane with a (not so good) glide ratio of about 4.5:1 (see What was the Space Shuttle's glide ratio?). No brick would be able to achieve that. Designing the Space ...

57

Same reason gliders keep their wings waxed. It wasn't the camo per se, it was the dull matte field-applied paint finish that included all sorts of imperfections, and to a small degree, the weight of the paint vs natural finish. At a microscopic level, the surface of the matte finish was much rougher than a gloss or unpainted metal surface. The ...

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: ...

40

Yes it's called a Deep Stall, and is mostly a problem with T Tail aircraft, especially jets with Supercritical Airfoil wings (like the CRJ Regional Jet line). Such wings stall from the leading edge and the stall's flow separation spreads rapidly and completely across the entire wing all at once, so there is very little residual nose down pitching moment. ...

40

I happen to own a homebuilt with tip tanks for ALL of the fuel supply (Pazmany PL-2), and while they look really cool, I'd prefer the fuel was in the wing leading edges mid span. There is no aerodynamic benefit. The tuna fish shaped tank doesn't function like a winglet (it has to be a wing to work like a winglet) and is too small to have any kind of end ...

38

As everyone has pointed out, it's a joke. Others have answered the lifting-body question (it didn't meet design requirements), so I just wanted to expand some thoughts on the spirit of the "flying brick" nickname. I suspect whoever came up with the term didn't spend a lot of time analyzing it. However, I think it's significant that the nickname is flying ...

35

It sounds very much what you're experiencing is a Phugoid cycle Image License info To put simply, your aircraft is not trimmed correctly. As it descends slightly it gains speed, which increases lift over the wing making it climb. This has the effect of it losing some speed, reducing the lift over the wing causing a descent, increasing the speed - and on it ...

34

If the cables break on an elevator (and the safety brakes fail), you won't be in true freefall. You'll still have friction from wind resistance, from the guide rollers on the rails, etc. The same is true in an airplane. Even if you're falling straight down, you'll still have wind resistance. In addition, lift doesn't just drop straight to zero when the wing ...

33

Problems with just making the fuselages wider: With the wing or main gear supporting the center of the fuselage, the front and back are cantilevered. Think of a hard landing or 2.5G pull up. The most effective structure to support bending is tall, with material on top and bottom (like an I-beam). A flat fuselage would have to be heavier to provide the same ...

32

I used to be an avionics instructor teaching maintenance type courses for the F/A-18. I have plenty of hours flying in the simulator where I would get the students to conduct navigation flights to familiarise themselves with the operation of the instruments as well as flight controls. I can confirm 100% that the rudder is barely touched once airborne. There ...

29

This PDF indicates an increase by ~10 dB for an F-8K in afterburner versus the same aircraft in 100% dry thrust. This PDF indicates smaller increases: +5 dB for an F-15 +4 dB for F-22 and F-35

27

The autopilot pitches to hold the flight level when it captures the level at the top of the climb, so later on as the aircraft gets lighter and wants to climb further, the A/P will lower the nose as required to hold the flight level (the A/P is able to move the elevator through its servo's link to the elevator controls; it can also work the trim if the servo ...

27

This is real easy, no explanation required: Tell your student to stick their hand out the window of the car driving 25mph in the city and rotate it like an aileron. Then have them do it on the freeway doing 60mph. Feel the difference? Did smaller movements produce larger effects at higher speeds? Practical examples are typically more effective at driving a ...

26

The short answer is no. All the glider feels is its flight relative to the air. What the ground is doing beneath it is not relevant, the wind could be blowing a hundred kilometers an hour and the glider would just be carried along without feeling a thing. This is why unpowered balloons always drift with the wind. To detect and respond to ground speed ...

25

Well, you only need so much vertical height between decks, say 7 or 8 ft, so once the tube diameter gets so big, you end up with simply too much wasted overhead space. Might as well jam some people up there, which means putting a second deck in.

25

Flaps out will reduce the ground run, but you're forgetting that they also increase drag. This is why you don't climb all the way to cruise altitude with flap extended. A 172 will climb better without flaps. With a take-off, you have to consider both the ground run and initial climb. After all, the take-off distance required is defined as the distance ...

24

It has been around 20 years since I've been on a carrier deck, but I recall that it wasn't as dramatic of an increase as you might think. It may have gotten a little bit louder, but what I remember more is that the tone changed. The sound was more "full" when the afterburner was engaged. I realize this is a rather subjective answer.

24

The fuselage is under pressure at altitude, and acts as a pressure vessel. The lightest pressure vessel we can build has a circular cross section. The wide body you mention sounds like a blended body shape, which may add lift but also weight as this answer mentions. We only need a certain height to walk around in a fuselage. Build a larger aeroplane with a ...

22

The best glide speed is the speed where tangent line from the origin (zero horizontal and vertical speed) touches power curve (for unpowered airplane). Best rate of the climb is the highest point of the power curve. When we start with unpowered airplane, the direct equivalent of best rate of climb is lowest rate of sink. The speed for lowest sink will be ...

22

The Concorde doesn't need reheat to cruise supersonically, just to get there (the range would be pretty short if it did). If it loses an engine it's not going to put the other 3 into reheat to hold altitude and speed (fuel burn) and it will do what just about all airliners have to do when at they lose an engine, descend to whatever its engine-out service ...

21

In addition to its poor glide ratio the shuttles name also stems from the materials its made from as much as it does its poor glide performance. The Space Shuttle's heat shield was made out of LI-900 Silica tiles that strongly resemble bricks and thus the shuttle was sometimes called the "Flying Brickyard". If you would like to know why NASA chose a wing ...

21

Most twin-engine aircraft with counter-rotating propellers have the rotation set up so that the propellers are rotating inward towards the center at the tops of the propeller arc. This configuration reduces the P-Factor effect at slow speed high angles of attack, and eliminates the "critical" engine that is present on multi-engine aircraft where both ...

20

Short answer: A cryogenic tunnel works by taking advantage of the different properties of nitrogen gas at cryogenic temperatures as compared to the properties of air at normal ambient conditions (speed of sound, density and viscosity). This allows testing at an order of magnitude higher Reynolds numbers over non-cryogenic tunnels. Being able to achieve full-...

19

It's primarily all about matte vs glossy finish. Normally a camo paint scheme would not be finished in a glossy finish as this might flash in the sunlight. A matte finish is rougher and thus has more air resistance than a glossy finish. The roughness is on a scale that is much larger than microscopic, but not obvious to the naked eye.

19

What you want is the roll constant $\text{T}_R$. This is basically one of the characteristics wich determines the equations of motion of an aircraft. It gives the slope of the roll speed increase over time with full aileron deflection and an ideally stiff wing, and equally the rate of decrease once the ailerons are set to neutral during a rolling maneuver. ...

18

The coffin corner is the altitude where your maximum speed (limited by high speed buffetting) is equal to your minimum speed (limited by low speed buffetting / onset to stall). The Concorde, when cruising at Mach 1, is not in the coffin corner, regardless of its engines health. Both the upper speed boundary and the lower speed boundary* of the flight ...

17

At what point does one say "oh, this flow has changed from turbulence to separation" At the point where the flow reverses direction. Flow separation. The bold curve is the surface/wing. Yes, that can happen. Both turbulent and laminar flow can separate. Turbulent flow is in fact less likely to separate than laminar flow. This is why aircraft ...

15

The rounded or elliptical design was found to be the cleanest aerodynamically in non-compressible subsonic airflow, which is why it's very common on aircraft of that era. While the design is very slippery for speeds of Mach < 0.6 or so, it is more difficult to manufacture, which is why, near the end of the war, Spitfires had the 'clipped' wingtips as ...

15

tl;dr: L/D of the airframe and specific fuel consumption of the engines are credible but that doesn't add up to the claims made regarding fuel consumption and speed relative to jets. Laminar flow seems to be used as the snake oil to sell this to gullible customers. The fuselage shape is inspired by a laminar flow airfoil, like the NACA 64-021 shown below, ...

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