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Enroute Airbus A380 wake flips Challenger business jet upside down

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Re: Enroute Airbus A380 wake flips Challenger business jet upside down

#151
post #144

Earlier quoted context omitted.

Every once in a while I have to re-realize how amazing this phenomenon is. The only thing in nature that flies are birds which weigh a few ounces. Nothing human-scale flies. Cars don't fly. Yet, the flying machines we decide to build weigh a million pounds and fly simply by going fast until the air lifts them up . That is some ludicrous black magic.

bats and many insects can fly too.

And small planes

Re: Enroute Airbus A380 wake flips Challenger business jet upside down

#153

Earlier quoted context omitted.

If you recall Boyle's Law from high school physics - Temperature is proportional to pressure. Aircraft wings generate an intense area of low pressure over the top of the wing (which is what essentially generates the lift). This low pressure area is magnified when flaps and slats are deployed. On a humid day, the lowering of the pressure over the wings can basically force the air temperature at that point to lower and…

Every once in a while I have to re-realize how amazing this phenomenon is. The only thing in nature that flies are birds which weigh a few ounces. Nothing human-scale flies. Cars don't fly. Yet, the flying machines we decide to build weigh a million pounds and fly simply by going fast until the air lifts them up . That is some ludicrous black magic.

Imagine seeing the quetzalcoatlus[1] fly...

[1] https://en.wikipedia.org/wiki/Quetzalcoatlus

Re: Enroute Airbus A380 wake flips Challenger business jet upside down

#154

Earlier quoted context omitted.

If you recall Boyle's Law from high school physics - Temperature is proportional to pressure. Aircraft wings generate an intense area of low pressure over the top of the wing (which is what essentially generates the lift). This low pressure area is magnified when flaps and slats are deployed. On a humid day, the lowering of the pressure over the wings can basically force the air temperature at that point to lower and…

Every once in a while I have to re-realize how amazing this phenomenon is. The only thing in nature that flies are birds which weigh a few ounces. Nothing human-scale flies. Cars don't fly. Yet, the flying machines we decide to build weigh a million pounds and fly simply by going fast until the air lifts them up . That is some ludicrous black magic.

There is no magic. If you look carefully enough you can see the string holding planes in the air.

Re: Enroute Airbus A380 wake flips Challenger business jet upside down

#155

> It's an incredible feeling, > lots of fun > Yes, it can be dangerous, > but it's a risk you can > manage yourself Try meth!

This is hilarious. But for the sake of the internet, I just have to say, no, really, don't actually try meth.

Re: Enroute Airbus A380 wake flips Challenger business jet upside down

#156
post #77

Earlier quoted context omitted.

That's a meaningless correction, and technically not correct. Aircraft are lifted up by air molecules hitting the underside of the rigid body with more force than the top side, by definition. The net integrated instantaneous pressure at the surface of the aircraft IS the lift. The fact that air gets deflected downward is a necessary (c.f. conservation of momentum) effect too. So it's not incorrect to do the analysis…

No, the effect is negligible if it wasn't planes wouldn't be able to fly upside down. It's the pitch of the wing that generates most of the lift. That's why helicopters don't alter the rotor RPM they adjust the pitch of the blades to take a larger bite.

The poster wasn't talking about the 'curved upper surface' myth. You can understand the lift to be a consequence of the pressure differential, and that is not inconsistent with planes flying upside down.

Re: Enroute Airbus A380 wake flips Challenger business jet upside down

#157
post #75
post #49

Earlier quoted context omitted.

Yeah I'm pretty sure that's the first rule that goes out the window when you're on a private jet.

Private planes also crash far more often than standard airline flights. Case in point: Chapecoense.

IIRC, the Chapecoense flight was done by a private charter company which provided services to football teams. That was not a private jet incident at all.

Re: Enroute Airbus A380 wake flips Challenger business jet upside down

#158
post #100
post #77

Earlier quoted context omitted.

That's a meaningless correction, and technically not correct. Aircraft are lifted up by air molecules hitting the underside of the rigid body with more force than the top side, by definition. The net integrated instantaneous pressure at the surface of the aircraft IS the lift. The fact that air gets deflected downward is a necessary (c.f. conservation of momentum) effect too. So it's not incorrect to do the analysis…

No, the correction is valid. The main component of lift is an upwards reactive force produced by pushing a mass of fluid downwards, in accordance with Newton's third law.

That is the only component of lift --- unless you think that Newtin's laws can be violated on a macro scale. But owing to the way that pressure is defined, the same phenomenon can also he understood in terms of a pressure differential.

Re: Enroute Airbus A380 wake flips Challenger business jet upside down

#159

Earlier quoted context omitted.

If you recall Boyle's Law from high school physics - Temperature is proportional to pressure. Aircraft wings generate an intense area of low pressure over the top of the wing (which is what essentially generates the lift). This low pressure area is magnified when flaps and slats are deployed. On a humid day, the lowering of the pressure over the wings can basically force the air temperature at that point to lower and…

Every once in a while I have to re-realize how amazing this phenomenon is. The only thing in nature that flies are birds which weigh a few ounces. Nothing human-scale flies. Cars don't fly. Yet, the flying machines we decide to build weigh a million pounds and fly simply by going fast until the air lifts them up . That is some ludicrous black magic.

A lightweight paragliding set can be as light as 3 kg these days, and experienced pilots can travel 200+ kilometers regularly with a tiny bit heavier set (say 8 kg).

Re: Enroute Airbus A380 wake flips Challenger business jet upside down

#160
post #79

Wow. Uncontrolled roll at least 3 times, maybe 5. G-loads severe enough to damage the airframe beyond repair. And this was a 9-passenger bizjet, not a tiny light single.

Compared to an A-380 a 9-passengers bizjet is a tiny feather.
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