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Apparently things are a bit more complicated in the air...

Drafting helps by reducing air resistance (drag) and requires you to be really close, this technique is a bit more subtle in that it involves using trailing air vortices to get free "lift". The article had a handy link to explain this... http://www.av8n.com/fly/vortex.htm

Of course I'm sure that someone will draw such an analogy in a pop-science article...

AOA is not indicated by the horizontal status of the aircraft body. It is a complex number derived from the airspeed, physical angle of the wing design, shape of the wing and the horizontal status. A simple bubble won't give you any indication of AOA.

http://www.av8n.com/how/htm/aoa.html

It doesn't matter what the distribution is, or even that you know the distribution, provided that you can put a lower bound on the entropy. See the Turbid project papers for details. Turbid is a project that uses quantum resistor noise in ordinary sound cards to provide guaranteed entropy for cryptographic use (though at a relatively low bitrate).

You can also use resistor noise, a good amplifier, and an ADC to make moderately high bandwidth true quantum RNG. I priced out a simple design with a microcontroller on a USB key footprint; looked like $50-100 in prototype quantities, less in large quantities, for 10 KB/s output (or so). Getting the entropy is looked like the easy part; it then needed a fair bit of CPU power (by microcontroller standards) to hash that into usable bits.

You can also (with a lot more software work, and low bitrates) use the resistor noise present in audio input channels to good effect. Turbid is a project that does just that. Note that when evaluating such projects, the hard part is not getting the numbers, but proving that they have enough entropy, and that they've been properly processed to preserve it. Turbid does an excellent job on this important documentation step.

You don't need a mic. The resistor noise on the sound card inputs is present and of secure quantum origin, regardless of whether a microphone is plugged in. The microphone noise is louder, but it's much harder to determine how much secure entropy is present. Why trust it when you don't have to? There's plenty available for most purposes without it. The Turbid program does this in an efficient and secure manner (and they have a paper discussing the details, along with the relevant proofs, for the curious).

Vapours are gas. Not all gases are vapours though.

I did some more research on vapour, and some people agree with your terminology, but I guess we're both 'correct', depending on who you're talking to. http://www.av8n.com/physics/vapor.htm has a decent go at making the distinction. I was willing to admit you're right if I could find proof, but I suppose my favourite part of that page with respect to our debate is:

Fog and clouds are visible but are neither gases nor vapors; they are aerosols, i.e. colloidal suspensions of very fine particles of liquid (or sometimes solid) H2O in the air.

If you also are so fucking stupid as to mess up two distinct states after whatever education you have, etc etc.. *shrug*

You are thinking that falling will cause low gravity and that can be sensed. However if you are also moving in a spiral the centrifugal force will compensate, and that's how you can fly into the ground without knowing it. Basically, all you can sense is the direction of the acceleration vector, but if it points downward it doesn't at all mean you are safe. If you follow the link above you will see that the spiral dive is specifically characterized by the acceleration (gravity + spin) vector being normal to the floor of the cabin, and the only hint you have (outside of the artificial horizon in front of your nose being tilted out of wazoo) is that this "gravity" may be somewhat stronger or weaker - which could also happen as you ascend or descend.

What then is the reaction to the lifting force? Remember all forces require an equal and opposite reaction - Newtons laws still apply at this scale.

The lift (due to pressure differences etc) needs a reaction force (required by Newton). You can't have one without the other. You can calculate the lift of a wing using lift coefficients, air density, velocity etc and lo and behold that force will be balanced by the mass x acceleration of the downward airflow. You can't have one without the other - the lift has to "push" against something.

You can't claim that significant amounts of air aren't directed downwards behind wings. Have you seen wingtip vortices in cloud? Could a helicopter hover without a downdraft? The wingtips vortices have an overall downward movement - planes can't fly without them.

http://www.av8n.com/irro/profilo1_e.html
http://www.av8n.com/how/htm/airfoils.html#sec-circ ulation-vortices
http://amasci.com/wing/whyhard.html
http://www.diam.unige.it/~irro/gallery.html

There is no one single effect that causes a wing to produce lift - it is a combination of interrelated effects:
http://www.av8n.com/how/htm/airfoils.html#sec-cons istent

What then is the reaction to the lifting force? Remember all forces require an equal and opposite reaction - Newtons laws still apply at this scale.

The lift (due to pressure differences etc) needs a reaction force (required by Newton). You can't have one without the other. You can calculate the lift of a wing using lift coefficients, air density, velocity etc and lo and behold that force will be balanced by the mass x acceleration of the downward airflow. You can't have one without the other - the lift has to "push" against something.

You can't claim that significant amounts of air aren't directed downwards behind wings. Have you seen wingtip vortices in cloud? Could a helicopter hover without a downdraft? The wingtips vortices have an overall downward movement - planes can't fly without them.

http://www.av8n.com/irro/profilo1_e.html
http://www.av8n.com/how/htm/airfoils.html#sec-circ ulation-vortices
http://amasci.com/wing/whyhard.html
http://www.diam.unige.it/~irro/gallery.html

There is no one single effect that causes a wing to produce lift - it is a combination of interrelated effects:
http://www.av8n.com/how/htm/airfoils.html#sec-cons istent

What then is the reaction to the lifting force? Remember all forces require an equal and opposite reaction - Newtons laws still apply at this scale.

The lift (due to pressure differences etc) needs a reaction force (required by Newton). You can't have one without the other. You can calculate the lift of a wing using lift coefficients, air density, velocity etc and lo and behold that force will be balanced by the mass x acceleration of the downward airflow. You can't have one without the other - the lift has to "push" against something.

You can't claim that significant amounts of air aren't directed downwards behind wings. Have you seen wingtip vortices in cloud? Could a helicopter hover without a downdraft? The wingtips vortices have an overall downward movement - planes can't fly without them.

http://www.av8n.com/irro/profilo1_e.html
http://www.av8n.com/how/htm/airfoils.html#sec-circ ulation-vortices
http://amasci.com/wing/whyhard.html
http://www.diam.unige.it/~irro/gallery.html

There is no one single effect that causes a wing to produce lift - it is a combination of interrelated effects:
http://www.av8n.com/how/htm/airfoils.html#sec-cons istent

It's interesting that you bring that first link up. The second link, Coanda Effect: Understanding Why Wings Work, is from no less than Jef Raskin, the father of the Mac. It contains a fallacious argument on why the Bernoulli effect can't explain the lift generated by a wing, which he claims he first derived as a child. It contains some child-like assumptions, the most grievous being the assumption that the ratio of the chord lengths (distance over the wing versus under the wing) is the same ratio as the speed of the air over the wing versus under. This implies that two air molecules that separate at the front of the wing, one going over and one going under, will meet at the back edge of the wing, as if joined by some invisible rubber band. In reality the ratio of the speeds is larger than the ratio of the chords, and the top molecule reaches the back long before the bottom one does. This link to a different page on the same website as the first Coanda fallacy link, shows the airflow using smoke pulses and does a great job of describing what is going on.

No. The Coanda effect is different than regular wing aerodynamics. The Coanda fallacy, the first external link on the coanda effect wikipedia article, explains the differences.

Kadin2048 said: Such a plane could fly low and slow to save fuel

Apparently you know nothing about the efficiencies of flight.

The ideal efficient flight profile is a parabola. Unfortunately, that would mean the aircraft is constantly changing altitude, so it would make air traffic nightmarish. The flight plans that aircraft file and fly today are a reasonable approximation to the 'ideal flight plan.' Basically, climb at Vclimb (most efficient power/drag speed) to the max altitude for the given weight and then 'coast' (descend) to the endpoint. Note that the max altitude is weight dependent, therefore transport jets often "step climb" where possible; once they get lighter from fuel burn, they climb again to a higher, more efficient, altitude.

If you'd like to learn how an airplane *actually* works, here's your URL -> http://www.av8n.com/how/htm/intro.html

The major problem with frost is not the change the shape of the airfoil; it disturbs the smooth airflow over the wing surface, causing turbulent separation, dramatically lowering lift.

http://www.ultralighthomepage.com/STALL/stall.html
http://www.av8n.com/how/htm/airfoils.html

The principal responsible is the Coanda effect

Jeff Raskin (he of Mac fame) also believed this. It is a complete fairy tale. Thoroughly debunked here. Among many other things, the Coanda effect simply cannot explain why there is upwash in front of a wing as well as downwash behind it.

How does an inverted aircraft remain both aerodynamically stable (relatively) and continue to maintain or increase altitude when the very airfoil shape that causes the Bernoulli effect is completely upside-down?

You're now doing what you accuse the gp of doing and misapplying Bernoulli as well. Ignoring boundary conditions, Bernoulli's principle does correctly predict a pressure drop on the upper surface of an airfoil but the reason is not because of some mythical property of fluids that disallow delay - it's because of circulation and the fact that a wing is very good at changing the speed of parcels of air. A wing is actually a very efficient pump that sets up circulation of the airflow by changing the speed of the air. Over the entire span of the wing (and the span is something normally ignored by Coanda fans), Bernoulli's principle says that there will be a suction force on the upper airfoil proportional to the pressure difference produced by the wing as it circulates the oncoming airflow. Upside down airfoils also circulate the air just fine, as long as the angle of attack is increased accordingly.

The tumbling sheet also generates lift. The sheet always rotates backwards with respect to the direction of flight, generating lift by inducing circulation around the "wing". The new thing the Cornell paper explains is why the paper's center of mass sometimes rises instead of gliding smoothly to the ground.