Root Access

bwDraco

6:00 PM

Hmm. It honestly sounds like these engines are ticking time bombs.

FML Cat

They all are. That's why they have inspection intervals and defined service lifetimes.

bwDraco

Dec 27 '15 at 6:27, by allquixotic

@bwDraco many reasons: there are no "non-professional" pilots in the air; the planes are much better maintained than most peoples' cars; planes go very fast, and travel many miles with lots of people, so a plane landing safely accounts for a very long time of driving for the same number of people; etc.

FML Cat

Yeah I took one flight and covered the equivalent of three years' worth of driving

I then took another two flights on the same day

allquixotic

we can't make 100% reliable machines, and the risks to human life involved in these particular machines' failure is incredibly high; so the only way we can keep people safe is through constant maintenance, vigilance, and being aware of pre-failure signs

analogy would be the extent to which a responsible, top-tier IT shop would go to safeguard business-critical records with customer information they can't afford to lose, like Google Docs or something

they have so much safety margin built in that you're pretty damn unlikely to lose a google doc

unfortunately we can't build aircraft with 8-way redundant RAID-1 engines ;)

FML Cat

Or Facebook user data... oh wait

allquixotic

6:05 PM

aircraft that have eight engines need at least most of them functional to be able to fly

FML Cat

@allquixotic We can, but it makes them uneconomical. Most planes can safely tolerate an engine failure just fine. None of the uncontained engine failures resulted in the loss of the plane.

allquixotic

@FMLCat except that Sioux City crash where debris from the engine cut all hydraulics

FML Cat

ETOPS certifications have gotten so ridiculous now modern planes are certified to fly for nearly a whole day with one engine down, which really means they really never need all engines. Ever.

@allquixotic That's neither a modern plane nor a typical case nor any of the cases we're talking about, but yes :-P

To deal with that problem we have redundant fly-by-wire systems, triple redundant hydraulics, and remote motors with redundant wiring that is disparately distributed to reduce the chances of any impact taking them all out

allquixotic

@FMLCat still, an engine exploding creates all kinds of risks that, while perhaps they only happen a smallish percentage of the time, you still don't want to be taking the risk of that very often, so reducing engine failures period is really important

FML Cat

Course you slice a plane in half with a missile it'll still go down, but really, engine failures don't crash planes these days.

allquixotic

6:08 PM

maybe the engine's explosion destroys or disables the fire suppression bottle (halon gas) and the engine catches the wing on fire, and the wing catches the cabin on fire

or shrapnel is severe enough to make the plane difficult to impossible to land safely due to disabling too many control surfaces

contained engine failures are probably fine but many of them are uncontained

FML Cat

Still I do wonder how that woman died on that SW flight, only reference I've seen is the window explosion "critically injured" her, no mention of engine debris

Fuel tank explosions, now those bring down planes.

bwDraco

Context of the linked message: Drivers ought to be trained in simulators.

FML Cat

Never seen an uncontained fuel tank explosion not bring down a plane

I've been trained in a car driving simulator... it's useless

bwDraco

For decades, aircraft pilots have been trained in simulators, letting them learn how to handle a variety of problems and failures safely.

But driver's ed is stuck in the past.

FML Cat

Cars don't have 40,000 controls you have to be familiar with in an emergency

It has two.

allquixotic

6:12 PM

@FMLCat I thought I read an article somewhere that claimed debris from the engine broke the window, and once the window was damaged it "exploded" outward like you said, and then sucked the upper half of her body out the window, until some passengers were able to pull her back in

FML Cat

Maybe three, if you count the door handle.

allquixotic

and honestly she probably died of suffocation because they were at 32,500 feet when it happened and it took them 5 minutes to descend, and her head was in that 32,500 feet low pressure air

FML Cat

@allquixotic Urgh, that... is nasty. People have died many times due to that... and one or two have survived but it's a rarity

bwDraco

You have a point... but simulation is the only way to quickly train drivers to safely handle dangerous situations on the road. People can learn defensive driving techniques in a simulator by simulating dangerous conditions like hydroplaning and reckless drivers. It would be impossible to teach these situations safely otherwise.

FML Cat

@allquixotic Apparently if your whole body is outside and you freeze it increases your chances of survival...

allquixotic

6:13 PM

the pressure forces keeping her pressed against the window were probably so high that she was unable to be physically pulled back by the two people pulling on her until they were down around 10,000 feet

jokerdino

D:

allquixotic

at which point, why bother because she'd have been asphyxiated by the low pressure air for several minutes

but they kept doing CPR, etc. trying to revive her all the way

and until they got her to a hospital

jokerdino

will be on that flight disaster programme one day probs

allquixotic

@jokerdino for sure; if they already wrote the scripts and did R&D for the 2018-2019 season then it'll be in the 2019-2020 season for sure

bwDraco

@allquixotic, your thoughts on how to make driving on the road safer?

Driver's ed seriously is stuck in the past. There's no technical reason why we can't teach drivers in simulators.

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