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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

#241

Post by gingerbread-man »

wallace_f wrote: post #220
gingerbread-man wrote: post #212

Earlier quoted context omitted.

For comparison, about 10,000 unrestrained motorists die in fatal vehicular accidents every year, and millions are injured. https://www.cdc.gov/motorvehiclesafety/seatbelts/facts.html

So according to this answer[1], ~1.7MM fly/day. Making a quick guess that from '80-'08, Americans average 1MM flights/day, then odds of serious injury are ~1 in 95,000. Odds of death are 1 in 9,333,333. Assuming the possibility of taking 3 'average' flights/day, then you'd need to board flights non-stop for 8,523 years to die, on average. 88 years to be injured. [1] - https://www.quora.com/How-many-people-fly-domesti…

Of course, general aviation is much more dangerous. As a general rule, the smaller the plane, the riskier it is, partially due to the corresponding increase in regulatory scrutiny as the size of the aircraft grows. Private pilots need a minimum of ~50 hours for their license. Most newly-hired jet pilots, private and commercial, have at least 1500 hours, and many have more than that.

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

#242

Post by Coincoin »

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

Planes are very fragile and are not meant to be able to sustain loss of control at high speeds. Sudden disintegration does happen mid air following a loss of control.

I am always impressed at how they look like a big chunk of metal from the outside, but they are in fact mostly made out of air and very thin and light materials.

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

#243

Post by CPLX »

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

When an airframe is stressed beyond its design limits it can't be put back into service. It's conceivable that it could be put through a "C-check" type process of disassembly and inspection, but given the age and residual value of the plane that might not have been cost effective.

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

#244

Post by gingerbread-man »

Right now, the vertical separation minima for aircraft worldwide are not conditional on size. At altitudes above 28,000ft MSL, the minimum vertical separation is 1000ft, even for superjumbos. It is probably a rare event that two aircraft come so close both vertically and horizontally, but I wonder if there will be a rule change because of this incident nonetheless.

By contrast, the horizontal separation minima vary dramatically based on the size of the leading aircraft.

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

#245

Post by dantillberg »

jabl wrote: post #179
ghshephard wrote: post #171

Earlier quoted context omitted.

To be clear - any cyclist crazy enough to ride a bicycle on the same road as cars definitely needs all the protection they can get, I think that goes without saying. But now you've moved from the "extraordinary low risk of accident" that comes from cycling to the "Probably one of the most dangerous things I can do" risk factor. And, pretty much 100% of the time I go snowboarding, I wear a helmet. What I'm trying to s…

Huh? Over here at least, people (me included) cycle on the same road as cars all the time. Not freeways, of course, but normal city roads with a speed limit of up to 50 km/h. It's actually illegal to cycle on the sidewalk unless there's an explicit traffic sign allowing bicycles.

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 absolutely not safe. It's one of the places where I think our legal code is absolutely bats--t crazy.

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

#246

Post by jen729w »

Moru wrote: post #174
jen729w wrote: post #141

Earlier quoted context omitted.

Here in Australia, where they're mandatory, us 'hipster' types get around this by wearing helmets that look like the sort of 'crash hat' that skateboarders wear: very dome-like, skull-shaped things rather than the traditional swept-back-vents-all-over helmets that your racing cyclist would wear. Hotter in summer, but they look cooler. ;-) FWIW, I thought it was weird at first having to wear a helmet. I'm from the UK.…

But a skateboard helmet doesn't work as well as a bicycle helmet when bicyckling. They are made for different falling types. They are better than nothing but not as good as the better bicycle helmets.

Sorry, thought about it at the time but didn't write it - they are actual bicycle helmets styled like skateboard helmets. They're fully rated for bike riding.

If the cops stop you (which they do, occasionally) and you are actually wearing a skate helmet, not rated for bike riding, that doesn't count as 'wearing a helmet' and you'll be fined.

(I'm sure the idea of being fined for wearing the wrong helmet will horrify some people but remember, that's the law here. The law also says you need a bell on your bike. It's rare, but the bike police do random stops and if you don't have a bell, strictly speaking, you'll be fined. Never happened to me, but it can.)

((Which, by the way - and sorry for the errata with the double-brackets - I actually support. I ride through central Melbourne. Pedestrians are a nightmare. Having a working bell is actually important. They cost $5. The law is a public service which, in this case, works. Get a bell.))

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

#247

Post by JshWright »

foliveira wrote: post #165

Good video of the same (similar?) effect on a small plane after taking off after an Antonov-2 http://www.youtube.com/watch?v=KXlv16ETueU

The rapid left/right pan of the music on that video is _super_ obnoxious if you're wearing headphones.

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

#248

Post by FussyZeus »

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

I'd imagine it's less a case of the plane being damaged heavily and more a case of there's just not enough value gained by keeping it in service to offset the potentially disastrous cost if something were to go wrong.

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

#249

Post by stereo »

nether wrote: post #41
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.

"Longer path" has no bearing on reality. A flat plate can generate plenty of lift even with both sides the same. It's also hard to define "path," as the air starts convecting well ahead of the wing in subsonic flow.

Yes, it’s hard to visualise for some people, but it’s the same reason why a small sailboat can turn with a flat rudder.

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

#250

Post by [deleted] »

Zak wrote: post #39
cyberferret wrote: post #36

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…

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.

[deleted]
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