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mangogrooveworkshop - 25/7/08 at 10:49 PM


JoelP - 25/7/08 at 10:52 PM

insane isnt it? Some VERY lucky people.


blakep82 - 25/7/08 at 11:02 PM

hmmm, its a weird one, can't work out how that panel would blow off like that


NigeEss - 25/7/08 at 11:29 PM

Things fail.
Be thankful it landed safely.

[Edited on 26/7/08 by NigeEss]


vinny1275 - 26/7/08 at 06:21 AM

Repair not done properly? It'll be on air crash investigations in a year or two....

at 30,000 feet it doesn't take much of a weakness to blow a panel out like that, the pressure difference between inside and outside is massive....


theconrodkid - 26/7/08 at 06:28 AM

http://www.dailymail.co.uk/news/worldnews/article-1038522/Huge-hole-terror-plunge-plane-caused-corrosion-spotted-March.html


if reports on an engineers site (pprune?) are true someone will be on gardening leave soon


thepest - 26/7/08 at 07:38 AM

quote:

at 30,000 feet it doesn't take much of a weakness to blow a panel out like that, the pressure difference between inside and outside is massive....



8 PSI to be precise...


mr henderson - 26/7/08 at 07:47 AM

From CRK's link-
"'In worst-case situations people can basically get sucked out of the aeroplane.' "

There was a scene like that at the end of Goldfinger.

It would make tremendous footage for you tube, imagine if someone could manage to hold on and could video his fellow passengers being sucked out of the hole one by one.

Probably the hole would get blocked as I expect there was probably some chubby people on that flight. Still, whoever ended up stuck in the hole would get an excellent view of the landing (as long as they were went through head first)

John


omega 24 v6 - 26/7/08 at 08:01 AM

quote:

Still, whoever ended up stuck in the hole would get an excellent view of the landing (as long as they were went through head first)



PMSL brilliant.


billynomates - 26/7/08 at 08:27 AM

Metal thieving pikey barstewards?


mr henderson - 26/7/08 at 08:30 AM

quote:
Originally posted by billynomates
Metal thieving pikey barstewards?



David Jenkins - 26/7/08 at 09:05 AM

What made me laugh (sarcastically) were the media reports similar to "Huge hole causes plane to plummet 20,000 feet!!!"

No - what probably happened was that the pilot realised he had cabin depressurisation and reduced height as fast as was safe so that the passengers could breathe without oxygen masks (which don't last very long).

But that doesn't make a good headline, does it...


Project7 - 26/7/08 at 09:38 AM

quote:
Originally posted by thepest

8 PSI to be precise...


But how many square inches was the panel? thats alot of force!


blakep82 - 26/7/08 at 11:03 AM

i like the man on telly saying something like "the pilot told us a door and blown out, he never told us it was anything as serious as this!"

hmmm, yeah, he also didn't get out to have a look did he? lol


TimC - 26/7/08 at 11:31 AM

Should have used sikaflex/tiger seal.


scotty g - 26/7/08 at 12:33 PM

quote:

What made me laugh (sarcastically) were the media reports similar to "Huge hole causes plane to plummet 20,000 feet!!!"



bloody over exagerating media nobs.
they drive my mad whenever a ship goes down somewhere and there are people in the water, it could be anywhere in the world and the media always describe them as being in "shark infested waters"
sharks don't infest the water they bloody live there and most of the time they mind their own business.
rant over.


JC - 26/7/08 at 02:50 PM

Aeroplanes such as 747 can lose at least the equivalent of 3 or 4 cabin windows and still maintain a cabin altitude safe for passengers. Standard procedure would be an emergency descent initiated by the pilot whatever kind of pressurisation failure they had. Not as good headlines though!
Would have been an interesting 2 or 3 minutes for the pax
during the emergency descent though!


martyn_16v - 26/7/08 at 09:27 PM

quote:
Originally posted by Project7
quote:
Originally posted by thepest

8 PSI to be precise...


But how many square inches was the panel? thats alot of force!


Most likely would have started as a much smaller hole, it won't have blown out as a single piece. Once it's got a failure, it'll just rip out to the nearest line of rivets, where it's supposed to stop (and indeed has).


Bob C - 27/7/08 at 08:09 AM

quote:Originally posted by Project7

quote:Originally posted by thepest

8 PSI to be precise...



But how many square inches was the panel? thats alot of force!



Most likely would have started as a much smaller hole, it won't have blown out as a single piece. Once it's got a failure, it'll just rip out to the nearest line of rivets, where it's supposed to stop (and indeed has).


8 psi sounds like the static pressure drop - wouldn't mr bernoulli have a say in a 500mph wind?
How do they do the emergency descents in these situations, cos you CERTAINLY wouldn't want to overspeed the airframe if something's just broken; can you deploy those "airbrake" flaps at cruising speed? does reverse thrust work? Does everyone get perforated eardrums? How long does it take to lose 20000 feet (that's about 3 miles innit?)


JC - 27/7/08 at 12:39 PM

In a situation where structural damage is suspected, the emergency descent is flown at the indicated airspeed that the damage occurred at -this ensures that the aerodynamic forces on the damaged area do not increase. Can't speak for the 747 but the aeroplane I fly comes down at 10000' per minute in an emergency! A 747 should be doing 5-7000 fpm I would guess, thus from 30000 to 15000 (the altitude at which pax will survive) - 3 mins, down to 9000 where it is safe for crew to unmask, another couple of minutes.

To descend, spoilers would be used - no speed limit for these and they just shed lift.

The only people to get perforated eardrums would be those with a cold or some other similar ear infection. It wouldn't be pleasant (done it in 'chamber' but no real problems! Don't fly with a cold!!!!!

[Edited on 27/7/08 by JC]


Liam - 27/7/08 at 03:33 PM

quote:
Originally posted by JC
Aeroplanes such as 747 can lose at least the equivalent of 3 or 4 cabin windows and still maintain a cabin altitude safe for passengers.


Really? Can't say i know, but that sounds insane! Maintaining several psi above atmospheric with a whole the size of even a single window would require the airflow of... I dunno, a small hurricane surely? Certainly way more than the cabin pressurisation fans could keep up with anyway, i would have thought. Surely hole that big = very fast depressurisation?

Liam


Bob C - 27/7/08 at 05:58 PM

Cheers JC - all sounds very sensible!


JoelP - 27/7/08 at 07:47 PM

quote:
Originally posted by Liam
quote:
Originally posted by JC
Aeroplanes such as 747 can lose at least the equivalent of 3 or 4 cabin windows and still maintain a cabin altitude safe for passengers.


Really? Can't say i know, but that sounds insane! Maintaining several psi above atmospheric with a whole the size of even a single window would require the airflow of... I dunno, a small hurricane surely? Certainly way more than the cabin pressurisation fans could keep up with anyway, i would have thought. Surely hole that big = very fast depressurisation?

Liam


i believe its to do with how small the windows are and how much air it lets in to keep it fresh. With windows out they close something called the outflow valve to maintain pressure. And yes, i just googled that


David Jenkins - 27/7/08 at 07:54 PM

BBC News