Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

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

avherald.com

Post reply on HN
Print view View original

81–90 of 152 posts

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

#81

Post by kogepathic »

cialowicz wrote: post #65
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.

The engines are designed so that a detached fan blade stays contained within the cowling. Here's a video of a fan blade containment test on a Rolls Royce Trent 500: https://youtu.be/RIOWjhjC1jM

> 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 coming out of the engine, so the fact that this seems to be relatively contained to the engine itself is fortunate.

[0] https://en.wikipedia.org/wiki/Qantas_Flight_32

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

#82

Post by yread »

SmellTheGlove wrote: post #30

It's amazing to me that modern aircraft engineering is so good that an engine can lose its fan blade entirely at 35000 feet and the plane can still continue on for 2 hours and safely land. An uncontained failure like this is the worst kind, and I know it could have gone worse, but it didn't and that amazes me. I wonder if the cowling contained the initial disintegration but was removed in the process. I'm not an engi…

There was also this much discussed incident

http://avherald.com/h?article=46a8f70a

where they just shut one engine down above canada and continued on 3 accross the atlantic to kuwait (they couldn't safely - with enough fuel reserve for multiple approaches and a diversion - reach dubai)

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

#83

Post by ansible »

CydeWeys wrote: post #51
SmellTheGlove wrote: post #30

It's amazing to me that modern aircraft engineering is so good that an engine can lose its fan blade entirely at 35000 feet and the plane can still continue on for 2 hours and safely land. An uncontained failure like this is the worst kind, and I know it could have gone worse, but it didn't and that amazes me. I wonder if the cowling contained the initial disintegration but was removed in the process. I'm not an engi…

The A380 has four engines in total, and can easily tolerate the loss of just one in normal flight. Adding more engines has been a basic way to increase reliability since the beginning of the field; it's not just modern aircraft engineering. There's no other part of the airplane behind the engines either, so nothing to be hit by debris. What amazes me more is that the newest twinjets are now considered reliable enough…

An engine-out situation does get interesting though when the aircraft is low and slow, such as when taking off and landing. That's where good training is needed to recover quickly and successfully.

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

#84

Post by [deleted] »

einrealist wrote: post #31
nabla9 wrote: post #2

It's more than just fan blade failure. Engines are tested against fan blade failures. The surrounding cowling should contain it. In this case the whole fan disk is gone. Uncontained failure like this can down the plane depending on the where the parts fly.

The fan failure was probably contained by the cowling. But the cowling broke right after because of stresses imposed by the damage and wind. If that's so, the cowling worked. The inner fans look damaged, so I assume the outer fan particles flew through the engine like expected.

[deleted]

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

#85

Post by gmueckl »

kogepathic wrote: post #81
cialowicz wrote: post #65

Earlier quoted context omitted.

The engines are designed so that a detached fan blade stays contained within the cowling. Here's a video of a fan blade containment test on a Rolls Royce Trent 500: https://youtu.be/RIOWjhjC1jM

> 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…

As far as I have picked up on that subject, passenger aircraft have multiple layers of protection against blades separating from the engine. The cowling is supposed to contain it. If that does not work, the fuselage in the area of the wings is hardened to prevent the separating part(s) from entering the passenger compartment and doing damage there. This is typically implemented using a Kevlar lining on the hull.

The Quantas flight is remarkable in that engine parts were not contained successfully and managed to damage critical systems inside the wing not related to the engine itself. Some reports say that the flight crew was overwhelmed by over 50 individual failure reports resulting from this damage. I was actually quite surprised when I learned that it was so easy to damage that many major systems with a seemingly small puncture in a wing.

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

#86

Post by JumpCrisscross »

gmueckl wrote: post #85
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…

As far as I have picked up on that subject, passenger aircraft have multiple layers of protection against blades separating from the engine. The cowling is supposed to contain it. If that does not work, the fuselage in the area of the wings is hardened to prevent the separating part(s) from entering the passenger compartment and doing damage there. This is typically implemented using a Kevlar lining on the hull. The…

Keep in mind that the Quantas failure, while horrible, resulted in zero fatalities.

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

#87

Post by bdamm »

JumpCrisscross wrote: post #86
gmueckl wrote: post #85

Earlier quoted context omitted.

As far as I have picked up on that subject, passenger aircraft have multiple layers of protection against blades separating from the engine. The cowling is supposed to contain it. If that does not work, the fuselage in the area of the wings is hardened to prevent the separating part(s) from entering the passenger compartment and doing damage there. This is typically implemented using a Kevlar lining on the hull. The…

Keep in mind that the Quantas failure, while horrible, resulted in zero fatalities.

Very remarkable indeed, considering the damage to the landing gear, flaps, fuel tanks, and engine controls. The airplane at the time it landed was way out into the experimental flying zone.

When people talk of pilot-less airliners I have to think of incidents like this. Pilots do make mistakes and people die as a result, but when equipment fails and nobody dies because a pilot does what is needed to land safely despite the issue, it rarely makes news. Sometimes people on board don't even know.

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

#88

Post by eesmith »

inferiorhuman wrote: post #46
eesmith wrote: post #14

Earlier quoted context omitted.

As your reference points out: "Newer aircraft designs such as the McDonnell Douglas MD-11 have incorporated hydraulic fuses to isolate a punctured section and prevent a total loss of hydraulic fluid." A quick search for "A 380 hydraulic fuses" finds sources like http://www.airliners.net/forum/viewtopic.php?t=765509 : > If one or both hydraulic systems fail, the following hydro-electrical backups remain available: For…

> And, "hopelessly intertwined"? Is that your viewpoint as a software developer, or are you an aircraft designer? Because I'm sure that an outsider would see my code as "hopelessly intertwined" even when it isn't. Even with modern aircraft, even with the A380, when a fan lets go or the engine grenades bad things happen. Qantas Flight 32, an A380, suffered a UCE and everyone was very lucky that there were additional,…

Sure. But do all those correct statements mean that the A380 hydraulic control systems, and their backups, are "hopelessly intertwined" to an aircraft designer?

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

#89

Post by mynewtb »

maxwer wrote: post #38

Sigh. The thing I miss about the internet in 1995 is that not everyone was an "aviation expert".

Sigh. The thing I miss about the internet in 1995 is that not everyone was signing up to a community just to spread negativity.

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

#90

Post by BrandoElFollito »

There were questions in the article and one close over here, but no answer AFAIK : how did the move people from one plane to another if they could not desimbark them in the first place?

Is the a way to connect two A380s together? (wild guess)

Post reply on HN