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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

#301

Post by ashark »

mannykannot wrote: post #208
chakalakasp wrote: post #202

Earlier quoted context omitted.

BTW the low pressure generating the lift thing is a myth. The lift is caused by the fact that the air is being deflected downward and good ol' Newton's Third Law.

The common explanation of lift for laypersons contains a number of non-sequiturs and even falsehoods, but this is not one of them. Newton's laws applied to the situation play out in complicated fluid dynamics, and result in a pressure difference over the wing, with a reduction above. That difference, summed over the wing, is the lift (and also the source of the induced drag, I believe, but that is a step beyond.)

Fun fact: One of the weirdest things about heavier-than-air flight is that upon posting any explanation for it online, several people will tell you you're wrong. Each of them will also disagree with one another. All will have sources.

[EDIT] This also happens with the Oberth Effect.

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

#302

Post by bdamm »

Retric wrote: post #277
jabl wrote: post #201

Earlier quoted context omitted.

The 'air molecules impinging on the airfoil' theory of lift is not wrong, but does not account for a large fraction of the lift generated either. In a dense enough medium such as air at normal flight altitudes, you have to take into account how those air molecules interact with other air molecules and not only the airfoil. Sum up all those interactions, and you get fluid dynamics rather than a molecule hitting a surf…

Fluid dynamics is a useful, but simplistic model. It's not actually true, but can accurately model truth.

Do you have a better model?

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

#303

Post by mikk14 »

gingerbread-man wrote: post #237
burkemw3 wrote: post #226

Earlier quoted context omitted.

I'm interested in hearing the intracacies!

There really aren't any good trick to it-- it's just a matter of finding a good vantage point and watching each driver go by. You're supposed to note the color of the belt (black) and the color of the driver's shirt before pulling the car over. As you'd imagine, fatigue comes quickly-- I never did more than an hour or two at a time. (I still have no idea how the highway patrollmen can it all day, every day without lo…

Legend says that in the streets of Naples they used to sell white T-shirts with a black band to simulate the seat belt :-)

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

#304

Post by xapata »

Neliquat wrote: post #262
xapata wrote: post #256

Earlier quoted context omitted.

charter ~ jet No?

Charter =/= Private To us it is the same, but to the person with a private jet, there is a substantial difference.

Ah, right. Like a weekly maid versus a live-in maid.

Still, as far as I know, the safety of standard commercial airlines is much better than both charters and private planes. Without the regulators to monitor the maintenance and pilots, it turns out people take more risks.

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

#305

Post by uzoodoo »

throwaway7767 wrote: post #213
Zombieball wrote: post #138

Earlier quoted context omitted.

Thank you! I'm probably heavily influenced by the fact that I live in one of these places (where helmets are a legal requirement). All I could think while reading this is "yes, you definitely should always wear a helmet!!"

Out of curiosity, is cycling a common mode of transportation where you are from? I recall seeing studies showing that helmet-laws generally coincided with low use of bicycles. Places where cycling is extremely common (like Denmark and Holland) never seem to have them, and it's uncommon to see cyclists using them unless they're doing something particularly dangerous (riding in traffic, off-road, etc).

I would guess in places where biking is extremely common (like Denmark and Holland), it's also a lot safer to bike (dedicated bike lanes, etc.)

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

#306

Post by ajross »

camperman wrote: post #297
ajross wrote: post #271

Earlier quoted context omitted.

> Air does not behave like a bunch of bullets hitting a wing Yes it does. And those bullet impacts are the very definition of pressure. The aerodynamics snobbery that you're trying to invoke is that those bullets also hit each other , so you can't make ideal gas assumptions and must model the whole system as a giant system of differential equations (c.f Bernoulli) if you want numbers out. That doesn't change the fact…

Nonsense. See here: https://www.av8n.com/how/htm/airfoils.html#sec-fluid

Yeah, that site is indeed one of the worst offenders. Try a fluid dynamics textbook. I genuinely don't think you understand what I'm saying. Air isn't magic fairy dust that pushes on airfoils from a distance. Pressure is impact.

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

#307

Post by macintux »

gingerbread-man wrote: post #237
burkemw3 wrote: post #226

Earlier quoted context omitted.

I'm interested in hearing the intracacies!

There really aren't any good trick to it-- it's just a matter of finding a good vantage point and watching each driver go by. You're supposed to note the color of the belt (black) and the color of the driver's shirt before pulling the car over. As you'd imagine, fatigue comes quickly-- I never did more than an hour or two at a time. (I still have no idea how the highway patrollmen can it all day, every day without lo…

I'm surprised. At least here in Indiana, as best as I recall, drivers cannot be pulled over for seatbelt violations, only if some other offense occurs.

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

#308

Post by bdamm »

leroy_masochist wrote: post #223
M_Grey wrote: post #64

Earlier quoted context omitted.

There's a reason that people with money and power don't always experience good outcomes. Sure, you can do what you like on your jet, and therefore expose yourself to risk that most people never experience. Likewise skiing off-piste or a number of other equally silly activities that you can do, but absolutely shouldn't.

Re: skiing off piste being a rich man's sport, are you familiar with the term "ski bum"?

Many sports have the same "X bum". Even aviation!

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

#309

Post by macintux »

dmix wrote: post #265
antubbs wrote: post #61

Earlier quoted context omitted.

Eh. e.g. the north atlantic tracks have been around since the 1960s. GPS wasn't available to the public until Korean Air Lines Flight 007 in the 1980s.

> until Korean Air Lines Flight 007 in the 1980s Woah, the soviets shot down a Korean airliner with air-to-air missles killing 269 people? Never heard that story. Crazy. https://www.wikiwand.com/en/Korean_Air_Lines_Flight_007

Yeah, that was definitely the #1 story in the news when it happened. Much like https://en.wikipedia.org/wiki/Iran_Air_Flight_655 there's no shortage of uncertainty around the real story.

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

#310

Post by lmm »

School-Cotton wrote: post #275
lmm wrote: post #273

Earlier quoted context omitted.

I don't remember the source, take that as you will. Cars go faster which means a higher risk of collisions (less time to react etc.), and also a higher risk of head injury per collision.

Maybe I'm just a shitty cyclist but I've wiped out way, way more times on a bike than in a car. You can crash without it being a "collision".

Did you hit your head though? Even "low" speed for a car can be 20mph; you can hit a stationary object and be thrown around pretty severely.

That said yeah if you're "wiping out" more than like once every few years you're doing something seriously wrong (or at least taking an unnecessary risk). I've only once had any kind of incident on my cycling commute.

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