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Air France A380 over Greenland on Sep 30th: Fan and engine inlet separated

avherald.com

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Re: Air France A380 over Greenland on Sep 30th: Fan and engine inlet separated

#131

Post by userbinator »

waqf wrote: post #122
gvb wrote: post #111

Earlier quoted context omitted.

The risk of minor injury (sprains, etc.) is pretty high for slides and there is some risk of serious injury (broken bones and worse). They are used when the alternative risk is death.

It doesn't seem fair to use the rate of injury during an emergency evacuation as a measure of what could be achieved with the same slides under non-emergency conditions.

The height is the same, and that's where those injuries come from. Those slides aren't like playground slides at all --- they are very, very high, and especially so on an A380.

Also, they need to be replaced if used, which costs extra time and money.

Basically, they are more like an airbag on a car.

Re: Air France A380 over Greenland on Sep 30th: Fan and engine inlet separated

#132

Post by bb611 »

cyberferret wrote: post #4

Seriously lucky that the disintegration didn't take out vital hydraulics or fuel systems in the wing, or penetrate the pressurised fuselage. I'd like to hope that this wasn't caused by ground crew error, i.e. an improperly secured cowling or access hatch, which snowballed into major component failure...

> Seriously lucky that the disintegration didn't take out vital hydraulics or fuel systems in the wing, or penetrate the pressurised fuselage.

It isn't luck. It is the result of millions of engineering hours spent on the development of highly reliable and resilient passenger aircraft, an emphasis on public identification and dissemination of design weaknesses, errors, and failures, and an unwavering focus by industry regulators on safety.

This is a particularly egregious failure mode and very hard to contain, but also one which a lot of design hours have been spent mitigating. They were very lucky to have suffered (apparently, as far as has been reported) no significant damage of any kind, but even an extremely egregious uncontained engine failure is frequently flyable because of the emphasis on redundancy in modern plane designs.

Re: Air France A380 over Greenland on Sep 30th: Fan and engine inlet separated

#133

Post by FabHK »

userbinator wrote: post #68
magnat wrote: post #64

That's the most neutral-point-of-view flight incident news article I've seen for quite some time. The whole site is so refreshingly level-headed.

AVherald is run by a single person who just compiles reports of incidents as they're received, so there's absolutely no editorialising goes on.

Yup, it's an absolutely brilliant resource. Simon sometimes injects some dry humour ("Incident: British Airways A388 near London on Mar 13th 2016, free shower in lower deck" [1]), but it's very level-headed, comprehensive, factual reporting. Well worth supporting, btw!

http://avherald.com/h?article=4957cf35&opt=0

Re: Air France A380 over Greenland on Sep 30th: Fan and engine inlet separated

#134

Post by FabHK »

laythea wrote: post #109

I think I will wait until these A380's are "broken in" before getting on one if I have the choice.

A380: first flight 2005, about 215 built

B787: first flight 2009, about 600 built

A350: first flight 2013, about 100 built

Off the three, I'd mostly avoid the 787. I still find the A380 the most comfortable, due to all the space. Lower cabin altitude in 787 and 350 is nice, but doesn't compensate for cramped conditions.

I'm a bit concerned about bleed air. (The high pressure air to maintain cabin pressure comes from the compressor stage of the engines, and could be contaminated with oil/fuel/?, and so far only the 787 has done away with that ("bleedless aircraft").) But, damn, that spacious A380 cabin.

Re: Air France A380 over Greenland on Sep 30th: Fan and engine inlet separated

#135

Post by FabHK »

ghaff wrote: post #103
CydeWeys wrote: post #52

Earlier quoted context omitted.

There's thousands of other more dangerous things you should worry about in your daily life. Like lightning or shark attacks. Now on the other hand, you could be taken out by an entire airplane crashing, e.g. https://en.wikipedia.org/wiki/American_Airlines_Flight_587

People on the ground were also killed as a result of the Pan Am Lockerbie bombing.

And quite a few when El Al 1862 crashed into a building near Amsterdam Shiphol airport (both engines on one side of the cargo 747 had come off, plus leading edge of the wing, and when they later slowed down for landing, that side stalled irrecoverably :-/

But that's not debris, that was a whole damn 747.

https://en.wikipedia.org/wiki/El_Al_Flight_1862

Re: Air France A380 over Greenland on Sep 30th: Fan and engine inlet separated

#136

Post by grkvlt »

lloeki wrote: post #123
katastic wrote: post #79

Earlier quoted context omitted.

According to this: https://en.wikipedia.org/wiki/Gliding_flight#Aircraft_.28.22... The 747-200 also has a glide ratio of 15:1. I can't tell if that's amazing, good, or average. A sailplane can have up to 60:1! That's pretty impressive! According to this: A "clean A320" has 17:1. Neat. https://aviation.stackexchange.com/questions/14814/could-a-c... Something I never knew was this: >As someone said above, you have to r…

Finesse gives you two things: Quite directly, from ground altitude, a range within which to look for a place to land. As you mentioned the impressive finesse of gliders gives you more room, but gliders won’t generally be flying as high as cruising powered planes. Combined with speed, a timeframe within which you have to observe, orient, decide and act. Here, both top speed and stall speed give you some hints, and wit…

Fineness, I assume? Although it'd be important to have finesse, too!

Re: Air France A380 over Greenland on Sep 30th: Fan and engine inlet separated

#137

Post by ajarmst »

WalterBright wrote: post #73
hueving wrote: post #71

Earlier quoted context omitted.

I suggest you watch the blade separation test videos. The entire point of the cowling is to contain fan blade loss.

The main purpose of the cowling is to improve the efficiency of the fan by preventing the air from being slung off radially. https://en.wikipedia.org/wiki/Ducted_fan

Agreed, but failure containment is another of its purposes, at least on contemporary turbofan engines.

Re: Air France A380 over Greenland on Sep 30th: Fan and engine inlet separated

#138

Post by WalterBright »

FabHK wrote: post #127
kogepathic wrote: post #81

Earlier quoted context omitted.

> The engines are designed so that a detached fan blade stays contained within the cowling. Yes, but uncontained failures can and do happen. Qantas Flight 32 is an example of an uncontained engine failure on an A380, though with a Rolls Royce engine instead of Engine Alliance (GE + P&W). [0] I do think they're very lucky that this uncontained engine failure didn't cause more damage. QF32 was heavily damaged by debris…

I'm fairly sure there are many other things that'll kill me first (hello, lack of exercise), but I do wonder where a detached turbine blade might cut through the fuselage and any passengers contained therein, and thus try to avoid the rows parallel to the engine. However, I'm wondering - would the blade go straight lateral? Or, relieved from having to pull the whole damn plane forward, would it fly forward and hit th…

The blades will come out radially.

If you're concerned about which seats are safer, the ones in steerage in the back are the safest. They tend to arrive last at the scene of the accident :-)

Good shoes can save your life, because you can walk out over hot, burning wreckage.

Wear cotton, not synthetic, clothes, and you'll have less severe burn injuries.

And, of course, pay attention to where the exits are and the flight crew's safety instructions. They really do know what they're talking about, and they're well trained.

Re: Air France A380 over Greenland on Sep 30th: Fan and engine inlet separated

#139

Post by WalterBright »

lb1lf wrote: post #106
WalterBright wrote: post #60

Earlier quoted context omitted.

> There's no other part of the airplane behind the engines either, so nothing to be hit by debris. The fans spin very fast, and will fly out radially, not just fall back. They'll slice right through anything they contact. The Airbus flight was very, very lucky.

Speaking of flying out radially, at least here in Norway, commercial prop planes had a broad red line painted on the interior cabin wall where prop blades would come knocking in case they were somehow torn from the hub. I have never heard of an incident where prop debris penetrated the cabin, but avoided the seats on that row if at all possible, just in case.

http://gawker.com/passenger-injured-by-broken-air-canada-pro...

https://en.wikipedia.org/wiki/Reeve_Aleutian_Airways_Flight_...

Re: Air France A380 over Greenland on Sep 30th: Fan and engine inlet separated

#140

Post by hueving »

WalterBright wrote: post #73
hueving wrote: post #71

Earlier quoted context omitted.

I suggest you watch the blade separation test videos. The entire point of the cowling is to contain fan blade loss.

The main purpose of the cowling is to improve the efficiency of the fan by preventing the air from being slung off radially. https://en.wikipedia.org/wiki/Ducted_fan

Did you ignore what I said and not watch the blade release tests?
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