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Comment by Neil44 | Hacker News Reader

Its also interesting that the corners of the windows are rounded - it's to avoid points of concentration for metal fatigue. We learned that lesson the hard way. When the De Haviland Comet was designed with square ones this was still poorly understood and there were several severe failures. The quest to find the cause of these failures at the time could be seen as the birth of modern air crash investigations.

Design evolution at work.

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The windows weren't quite square panes, they were slightly rounded, but not enough.

Another issue the Comet had were the engines buried in the wings, which makes them less accessible for servicing and more dangerous to the aircraft in the event of failure/explosion.

Engines buried in the wings was first and foremost aerodynamic problem. Today we know that intakes must be kept from messing with the airflow above the wing where most of the lift is generated.

most lift is not generated above the wing but due to angle of attack which is the angle of the wing relative to the flight path.

Right you are! Normally I would hate to be that guy, but here's the obligatory XKCD:

http://xkcd.com/803/

It's way more complicated than that:

http://flighttraining.aopa.org/magazine/1998/November/199811...

Sure. A follow-up question I would have asked: how do propellers work? By accelerating large volumes of air, force is generated according to Newton's Second Law. So do wings accelerate large volumes of air? Of course, as one can see at any airport, large vortices trail behind and below the wings of any airplane or glider. So how is a wing different than a propeller?

That's a weird text. At the beginning the author lists reasons why it's clearly Newton's third law, and then just basically says: "But then an 'authority' on aerodynamics waved hands around telling me it's not. The end." Maybe I misread something, but nowhere in the examples that are apparently inconsistent with Bernoulli's law, and for which the professor claims they actually support it, does he actually provide an explanation.

I didn't say it wasn't complicated. What I said was most lift is due to angle of attack.

The fact is that the percentage of lift that is attributable to angle of attack is far greater than that due to reduction in air pressure across the curved part of the wing.

Roughly 80% of the lift is generated above the wing in typical aircraft. Angle of attack is part of it and not a counterargument.

As the angle of attack is increases, the point of minimum pressure moves forward and the size of the adverse pressure gradient increases.

btw. In most most airfoils zero angle of attack and zero lift axis differ. The wing generates lift even without the angle of attack. Chambered wings are exception to this.

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