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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

#291

Post by termain »

cyberferret wrote: post #48
Zak wrote: post #39

Earlier quoted context omitted.

Wings generate lift primarily by deflecting air downward. There is an area of low pressure over the wing where air is taking a longer path than under the wing, but that is only responsible for a small fraction of the lift.

Well, the same Venturi principle applies if you look at it in terms of laminar airflow over the wing. The top of the wing (via curvature and downward deflection) is essentially creating a widening venturi tube, whereas the bottom of the wing is creating a closing venturi tube. (Oh, ok, it is planar rather than a tube, but the principle is essentially the same). Hence the high pressure under the wing and the low press…

Yes to pressure part and no to the venturi part. Well, it's not enough. You still have to generate a downdraft to conserve momentum and the venturi idea doesn't explain that.

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

#292

Post by M_Grey »

matsemann wrote: post #107
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.

Not sure why you are calling off-piste skiing silly, a rich man sport and something one shouldn't do. It's an incredible feeling, lots of fun, and if you have to walk up the mountain first it's a nice nature experience as well. Yes, it can be dangerous, but it's a risk you can manage yourself. So it doesn't have to be very dangerous if one follows common advice and also don't ski where there is a high risk of avalanc…

Yes, it can be dangerous, but it's a risk you can manage yourself.

Probably what Michael Schumacher thought to himself, back when he could still think.

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

#293

Post by M_Grey »

koliber wrote: post #152
peteretep wrote: post #130

> 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 comment thread quickly deteriorated from civil discussion to absurdist comparisons.

Except that it's not. In the UK you can go to prison for pot, which is less dangerous than (for example) horseback riding. Its the situation which is absurd, not the comparison.

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

#294

Post by nanistheonlyist »

ajross wrote: post #271
camperman wrote: post #182

Earlier quoted context omitted.

Air does not behave like a bunch of bullets hitting a wing. It's a fluid with velocity and pressure everywhere, not simply in the vicinity of aircraft surfaces. A wing is a pump that sets up circulation in the airflow, upward of the leading edge and downward off the trailing edge. The downward momentum of the air flowing off the trailing edge produces an equal and opposite reaction by Newton's third law which is the…

> 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…

A casual perusal of ww2 videos clearly shows that bullets hitting a wing tends to cause planes to crash, whereas air hitting a wing tends to cause them to fly. This bleedingly obvious point says some very bad things about the way the aviation community has tried to teach history.

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

#295

Post by M_Grey »

School-Cotton wrote: post #268
dantillberg wrote: post #245

Earlier quoted context omitted.

When I lived in Boston, it was certainly legal to ride bicycles in the road (and illegal to ride them on many sidewalks), but cyclists still got hit by cars all the time. Riding with cars (whether in your own "lane" sandwiched between parked cars and moving cars, or in the same lane as the cars that want to bolt ahead at 40 mph whenever they have the chance) is the only legal option to get around by bike, but is abso…

Where the fuck are you supposed to ride them, then? Sure I'd love it if cities built separated bike paths everywhere people want to commute, but that's far from reality currently

Boston has bike lanes, so... that would usually work.

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

#296

Post by M_Grey »

tajen wrote: post #149
webignition wrote: post #112

Earlier quoted context omitted.

Yes, you should absolutely wear a helmet when riding a bicycle at low speeds. Your skull is vulnerable to impacts at speeds that are relatively low compared to full-speed cycling. On a few occasions I've witnessed a cyclist panic and wobble after being passed far too closely by a car traveling far too fast for such a manoeuvre. This has caused such cyclists to wobble, inadvertently clip the curb and mount the pavemen…

Yours are anecdotal evidence of an extremely low risk. There are some bike accidents, which are already rare; Very few involve the head; and even fewer would be saved by a helmet. Whereas, requiring a helmet is a sufficient disincentive to biking that studies have shown that it increases the number of deaths in countries that made it mandatory, by making people drive instead and later die from cardiac diseases and ob…

"Thinking is pointless, just like motorcycle helmets!"

"Rafi, how many of your friends have died in motorcycle accidents?"

"Pfft, nine. Buy NONE of them were from head trauma, they all died from massive spinal trauma."

Be honest... are you just playing the reference game, or do I need to be really worried?

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

#297

Post by camperman »

ajross wrote: post #271
camperman wrote: post #182

Earlier quoted context omitted.

Air does not behave like a bunch of bullets hitting a wing. It's a fluid with velocity and pressure everywhere, not simply in the vicinity of aircraft surfaces. A wing is a pump that sets up circulation in the airflow, upward of the leading edge and downward off the trailing edge. The downward momentum of the air flowing off the trailing edge produces an equal and opposite reaction by Newton's third law which is the…

> 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

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

#299

Post by randcraw »

elberto34 wrote: post #238

I wonder the private plane had to be written off...was the damage that bad? It's like the plane broke apart ..maybe the probems were mostly internal

As an uneducated guess, the wing mounts (aluminum?) and surrounding fuselage have stretched way beyond tolerance and are no longer capable of supporting nominal load. The metal has fatigued and must be replaced, which would require new wings and nearby fuselage -- at no small cost.

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

#300

Post by uzoodoo »

throwanem wrote: post #194
sundvor wrote: post #62

Earlier quoted context omitted.

True.I would think this would be more of a problem for people from US states where wearing a seatbelt is not mandatory. In other parts of the world (with more sense) such as Europe, Australia, we're conditioned to always using it due to strict enforcement and as such it's not such a novelty.

The only such US state is New Hampshire. (Because of course it is.)

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