If you can read this, either the style sheet didn't load or you have an older browser that doesn't support style sheets. Try clearing your browser cache and refreshing the page.

(LA Times)   Investigators: Air France 447 pilots had to deal with a cascade of simultaneous system failures   (latimes.com) divider line 200
    More: Followup  
•       •       •

15662 clicks; posted to Main » on 13 Jun 2009 at 9:57 PM (5 years ago)   |  Favorite    |   share:  Share on Twitter share via Email Share on Facebook   more»



200 Comments   (+0 »)
   

Archived thread

First | « | 1 | 2 | 3 | 4 | » | Last | Show all
 
2009-06-13 08:13:48 PM  
Way to go Mr. Romero-- I never would have guessed that there would be a whole host of system failures the moment you're hitting water at 500 miles per hour.

/snark off
//of course I didn't RTFA
 
2009-06-13 08:36:18 PM  
006andahalf: I never would have guessed that there would be a whole host of system failures the moment you're hitting water at 500 miles per hour.

I'm pretty sure the system failures began at altitude, the leading theory being either a stall or overspeed situation possibly resulting from a failed (clogged) pitot tube. Basically a freak situation any way you look at it, but I hope they get to the bottom of it and fix whatever equipment or procedures are necessary to ensure it doesn't happen again.

/didn't RTFA either, off to do so now.
 
2009-06-13 09:01:02 PM  
I know. Like I said, snark.

The most interesting paragraph may be this one:

"The flight laws that Airbus programs into its computer embrace a fundamentally different approach to flying than those used by Boeing, which gives humans far greater authority to fly the plane, according to a wide range of pilots interviewed by The Times."

It goes on to note that these flight laws, combined with the environmental situation may have led to a complete structural failure of the control surfaces. Also worthy of note was that it appears that the systems that would allow the pilots to fly the plane themselves may have gone offline so they would have had virtually no clue which way was up. They could have thought they were going straight along when they plowed into the surface. This also makes it a lot easier in ugly weather conditions to overstress the control surfaces without even knowing it.

/father of a friend of mine in the industry despises Airbus' fly-by-wire system, and so far all of his criticisms appear to have played out.
 
2009-06-13 09:05:49 PM  
006andahalf: "The flight laws that Airbus programs into its computer embrace a fundamentally different approach to flying than those used by Boeing, which gives humans far greater authority to fly the plane, according to a wide range of pilots interviewed by The Times."

It's a double edged sword I guess. On one hand, limiting the extents of the control surfaces in certain situations can prevent grave pilot errors. On the other hand, it could also prevent spectacular desperation maneuvers that could possibly save the aircraft. Seems to me like a no win situation.

/not an aviator, maybe somebody who is can give a better analysis here.
 
2009-06-13 09:16:52 PM  
Fly-by-wire systems, such as the one used by airbus are usually good at making it easier and safer to fly the plane, but the problem with a computer doing this is that it relies on indicators of the outside, and those indicators from the outside can be fooled, much like a pilot can. The problem with the airbus system is that it is much more difficult to over-ride when it is being fed incorrect information.

Another spectacular example of fly-by-wire systems going haywire due to faulty indications is the case of the B-2 which went down in Guam. Condensation built up in its angle of attack indicators, which made the airplane think it was at a very high angle of attack, so when the airplane tried to take off, and the pilot pulled the stick back, the system thought he was trying to stall the airplane and the airplane promptly responded by putting itself into the ground. Of course, the B-2 is unflyable without a fly-by-wire system, but I don't believe the A-330 is. It is a pretty traditional design.
 
2009-06-13 09:51:44 PM  
People, people. Fly-by-wire != flight envelope protection.

It surely makes flight envelope protection a lot simpler, but there is a difference. I would say more, but I gotta be at the gym in 26 minutes.
 
2009-06-13 09:56:30 PM  
Too bad the "Black Box" is probably gone forever.

As I understand it, the box was designed to send out audio "Pings" every so often if it detects it is under water. But the on board batteries can only last so long.

I wonder why the boxes were not designed with that problem in mind-- instead of blindly pinging every few minutes, why not design it to wait and listen for a ping from a search craft before sending out an energy consuming pulse of sound?

I'm sure the engineers thought of this long ago and decided not to implement it for some reason. I wonder what that reason was?


=====================================

Even better, maybe someday planes can be constantly streaming its flight data straight to communication satellites for storage at a ground station. The technology to do this exists now-- as TFA shows a similar system on a limited scale provided what little data was available. I suspect it would be a real biatch to fully implement such a system on a global basis.
 
2009-06-13 09:56:35 PM  
006andahalf: Fly-by-wire systems, such as the one used by airbus are usually good at making it easier and safer to fly the plane, but the problem with a computer doing this is that it relies on indicators of the outside, and those indicators from the outside can be fooled, much like a pilot can. The problem with the airbus system is that it is much more difficult to over-ride when it is being fed incorrect information.

This is all true, but if you look at this accident with the theory in mind that the flight control system failed because something blocked all 3 dynamic pressure sources simultaneously, what was the outcome likely to be in any aircraft in such a situation? You've got what's supposed to be a triple-redundant system, and it's completely gone. At night. In a thunderstorm. No source of airspeed information whatsoever. Then your attitude reference goes offline.

If the FBW system doesn't have the information to fly the plane, neither do the pilots unless they can get that information by looking out the window.

All the speculation around this crash seems to (inevitably, to be fair) center on the idea that the one of the very few things we know about the aircraft (ACARS error message contents and the recovery of the vertical stab) must be the cause of the accident. I get that we don't have much else to talk to, but there's no real reason at present to suspect that anything that's been discovered so far is the smoking gun, so to speak.
 
2009-06-13 10:05:12 PM  
I'm curious if failures can be programmed into the flight computer. If so, it would be a pretty slick way to bring an airplane down.
 
2009-06-13 10:05:15 PM  
nekom: I hope they get to the bottom of it

Most did.
 
2009-06-13 10:06:02 PM  
FTFA: "Scarebus officials warned against reading too much into the failure of the airspeed sensors."
 
2009-06-13 10:06:10 PM  
And all those simultaneous failures could never be caused by a massive internal combustion right? In fact why would anyone even consider such a thing?
 
2009-06-13 10:06:49 PM  
What the warning lights may have looked like

i230.photobucket.com
 
2009-06-13 10:06:49 PM  
I wonder if there's any connection to the south Atlantic magnetic anomaly?
 
2009-06-13 10:07:48 PM  
If the debris is truly spread over 80+ miles of ocean, (from other articles) I don't see how pitot tube failure can be a primary cause, or even lead to a primary cause.

I can see how flying blind with a system not meant to have humans save the flight can crash the thing, but I can't see how that system could break up the plane over such a wide distance and strip some bodies of clothing at the same time.
 
2009-06-13 10:07:54 PM  
SuperCatBarf: I'm curious if failures can be programmed into the flight computer. If so, it would be a pretty slick way to bring an airplane down.

Sir, the DHS, FBI, FAA, and Secret Service would like to have a word with you.
 
2009-06-13 10:10:09 PM  
Boeing vs Airbus discussions amuse me. It's funny to see people argue about aircraft companies that build to the same safety standards. I should make a bingo card or something.
 
2009-06-13 10:11:25 PM  
Yikes.. Sounds like they got hit by some foam upon takeoff..
 
2009-06-13 10:11:55 PM  
Can't help but feel for the flight crew if they look down and see...
i237.photobucket.com

My sympathies to all who were affected by this.
 
2009-06-13 10:16:24 PM  
haha man, more like AIR FREEDOM am I right? Huh? Get it? The French sure surrender a lot. Boy oh boy do they! Let me try this again... "MORE LIKE AIR FREEDOM INSTEAD OF FRANCE..." Man it's 2001 again and there's no where for pricing houses to go but up!
 
2009-06-13 10:18:35 PM  
ElLoco: nekom: I hope they get to the bottom of it

Most did.


i533.photobucket.com

So you might say a Cascade of failures ended with a final rinse?


/window seat please. just not on Air France
 
2009-06-13 10:20:07 PM  
Elvis Da King: Can't help but feel for the flight crew if they look down and see...


My sympathies to all who were affected by this.


It's official, we need OS-X on the system!.
 
2009-06-13 10:21:53 PM  
1. The Bush administration knew all about this. George Bush's cousin owns the company in charge of security at the airport.
2. The Bush family is a majority owner in Boeing and stands to make millions now that the Airbus is seen as dangerous.
3. There were no Jews on the flight. They were all warned to wait for the next plane.
4. No plane could possibly crash like that without well placed explosives on board.
5. Brazil has a lot of oil. This was an obvious plot to give Dick Cheney an excuse to invade Brazil to take over the oil fields and give the money to his cronies.
6. The flight was from a country full of brown people to a country full of light brown people, so it was obviously a devious plot by white supremacists, AKA the Bush Administration and all Republicans.
7 thru Infinity. - Blah, blah, blah.
 
2009-06-13 10:21:54 PM  
FBW suks...

I like fly by pilot!
 
2009-06-13 10:22:11 PM  
nekom: 006andahalf: I never would have guessed that there would be a whole host of system failures the moment you're hitting water at 500 miles per hour.

I'm pretty sure the system failures began at altitude, the leading theory being either a stall or overspeed situation possibly resulting from a failed (clogged) pitot tube. Basically a freak situation any way you look at it, but I hope they get to the bottom of it and fix whatever equipment or procedures are necessary to ensure it doesn't happen again.

/didn't RTFA either, off to do so now.


Airliners should have more than one.
 
2009-06-13 10:23:57 PM  
If it's not Boeing,
I'm probably not going.
 
2009-06-13 10:25:36 PM  
I find the scariest part about AF447 is that we might never know for certain why that plane went down, meaning no one can fix the cause(s) behind the crash.

/Do hope the FDR & CVR are found
 
2009-06-13 10:28:49 PM  
"Not only did they lose their speed readings, but they may have lost their artificial horizon," Pollard said. "And I can tell you that you might as well give up. In the day, it's fine, when you have the horizon in front of you."

Ouch. Flying through a thunderstorm with no horizon and everything falling apart all around you. You probably don't trust your airspeed readings, but you have more pressing problems, like which way is up. Poor bastards.
 
2009-06-13 10:31:28 PM  
Fly by wire sounds a lot like if you wanted to make a remote controlled pancake flipper tha also turned over bacon, and hooked it up to a fool proof Windows 98 PC for the wi fi you would need to operate it, then added on a battery back up, with a plug in device that could come unplugged anytime, and then decided not to have any back up. At all. Ever.
 
2009-06-13 10:32:53 PM  
If the speed sensor tubes became blocked, why couldn't planes be set with some sort of GPS or transponder sensor that would give them redundant speed and altitude info. It seems like relying on an easily clogged tube to give you flight data is dumb.
 
ZAZ [TotalFark]
2009-06-13 10:33:14 PM  
For the other point of view on the Airbus-Boeing battle of design philosophy, a Boeing crashed into the top of a mountain in Colombia in 1995 under circumstances where the Airbus "we're smarter than you" computer might have saved the plane. The pilot did not retract spoilers when pulling up. Airbuses are programmed to do that automatically.


TFA on the artificial horizon: The Airbus A-330, like most modern jets, has a backup system that would have provided the information. Whether it was available or also compromised is unknown.

Isn't the backup supposed to be a mechanical system not connected to the HAL-330 artificial intelligence unit?
 
2009-06-13 10:33:33 PM  
SVenus: If the debris is truly spread over 80+ miles of ocean, (from other articles) I don't see how pitot tube failure can be a primary cause, or even lead to a primary cause.

A stall in a jumbo jet isn't nearly as controllable as in a light plane, especially if one wing stalls and causes a spin. So tells my pilot friend. On the other, if it was going too fast through the storm, would it be possible for a tail failure to occur? Not sure, but I could have sworn an article I read mentioned a jumbo jet going too fast or too slow through a strong storm could possible result in a mid air break up.
 
2009-06-13 10:34:07 PM  
Wow... I never thought I'd actually see a resonance cascade...
 
2009-06-13 10:34:34 PM  
Air France surrenders?
 
2009-06-13 10:35:46 PM  
The really weird part is - why was there no communication from the cockpit? The aircraft was apparently able to phone home. Why nothing from the crew? Even just a fragment.."HELP!"
 
zz9
2009-06-13 10:37:15 PM  
SVenus: If the debris is truly spread over 80+ miles of ocean, (from other articles) I don't see how pitot tube failure can be a primary cause, or even lead to a primary cause.


Blocked pitot tubes have led to crashes before, even on Boeing's.
If the ASI is telling you you're going too slow you'll speed up and overspeed the airframe, possibly ripping off control surfaces.
If it tells you you're going too fast you'll slow down and stall, which combined with losing the AI and with no visual horizon would make it impossible to recover.
Both these scenarios could lead to massive over stressing of the airframe and a break up long before hitting the water.
 
2009-06-13 10:37:19 PM  
ElLoco: nekom: I hope they get to the bottom of it

Most did.


You farking bastard, I hope my going to Hell for laughing at that makes you happy!
 
2009-06-13 10:37:21 PM  
SCUBA_Archer: If the speed sensor tubes became blocked, why couldn't planes be set with some sort of GPS or transponder sensor that would give them redundant speed and altitude info. It seems like relying on an easily clogged tube to give you flight data is dumb.

GPS gives ground speed information. FTFA:

Pilots rely on several instruments for speed information. A system of laser gyroscopes and a separate GPS system can tell pilots their ground speed. But the pitot system provides data about the speed of air flowing across the wings, crucial to maintaining lift.
 
2009-06-13 10:38:34 PM  
Airfoilsguy

What the warning lights may have looked like

And to add insult to injury, it tells you you're farked in bad grammar.
 
2009-06-13 10:38:44 PM  
Obnox: Ouch. Flying through a thunderstorm with no horizon and everything falling apart all around you. You probably don't trust your airspeed readings, but you have more pressing problems, like which way is up. Poor bastards.

Yeah, here's the list
http://www.nytimes.com/imagepages/2009/06/13/world/13plane.grafic.ready.html (new window)
 
2009-06-13 10:39:37 PM  
YouPeopleAreCrazy: The really weird part is - why was there no communication from the cockpit? The aircraft was apparently able to phone home. Why nothing from the crew? Even just a fragment.."HELP!"

Um, I think that they were kinda busy with trying to fly the plane and did not have time to phone home.
 
2009-06-13 10:39:39 PM  
the pilots were french

just sayin'
 
2009-06-13 10:40:24 PM  
zz9:
If it tells you you're going too fast you'll slow down and stall, which combined with losing the AI and with no visual horizon would make it impossible to recover.
Both these scenarios could lead to massive over stressing of the airframe and a break up long before hitting the water.


Yeah, the last message was the decent going down 1800ft a minute, but even if it was broken up at that point, I can't see how debris got scattered over 85 miles.
 
2009-06-13 10:40:25 PM  
Airfoilsguy: What the warning lights may have looked like

Your != You're
 
ZAZ [TotalFark]
2009-06-13 10:40:43 PM  
If the speed sensor tubes became blocked, why couldn't planes be set with some sort of GPS or transponder sensor that would give them redundant speed and altitude info.

Usually you can live for a while without airspeed indication if nothing else goes wrong. Something else went wrong.

(I'm not sure if an A330 at cruise is an exception to the rule -- there are airplanes with a small margin between minimum flying speed and maximum mach number at high altitude.)
 
2009-06-13 10:42:35 PM  
www.fantasticfiction.co.uk
 
zz9
2009-06-13 10:44:12 PM  
SCUBA_Archer: If the speed sensor tubes became blocked, why couldn't planes be set with some sort of GPS or transponder sensor that would give them redundant speed and altitude info. It seems like relying on an easily clogged tube to give you flight data is dumb.

Ground speed (which is what GPS gives you) is not airspeed. Ground speed is useless to a pilot. At this sort of altitude and conditions there could easily be more than 100kts difference, plus or minus, between GS and IAS.

Also altitude is what determines separation between flights on the same flightpath. All aircraft use a standard barometer setting. It may be wrong, but it will be exactly the same amount of wrong for the plane heading towards you at a closing speed of a thousand miles an hour and only a thousand feet above or below you.
If he was suddenly at a height determined by barometric pressure and you were using GPS then you might actually be at the same height...
 
2009-06-13 10:44:51 PM  
Just how simultaneous were these failures? Seems like the transmission capacity of ACARS is quite limited and the conditions weren't good. Did everything fall apart over the course of four minutes, or could they occurred much closer together and only their transmission was spread out?
 
2009-06-13 10:47:11 PM  
SpeckledJim: Just how simultaneous were these failures? Seems like the transmission capacity of ACARS is quite limited and the conditions weren't good. Did everything fall apart over the course of four minutes, or could they occurred much closer together and only their transmission was spread out?

I pasted the link to the NYTimes of the graphic that has the warning/failure messages. 2:10 is the first flurry, and 2:14 UTC is the last.
 
2009-06-13 10:48:08 PM  
One Thirty-two and Bush: So you might say a Cascade of failures ended with a final rinse?


/window seat please. just not on Air France


Came for this reference and the pun was a bonus!
Leaving very impressed.
 
Displayed 50 of 200 comments

First | « | 1 | 2 | 3 | 4 | » | Last | Show all



This thread is archived, and closed to new comments.

Continue Farking
Submit a Link »
On Twitter





In Other Media


  1. Links are submitted by members of the Fark community.

  2. When community members submit a link, they also write a custom headline for the story.

  3. Other Farkers comment on the links. This is the number of comments. Click here to read them.

  4. Click here to submit a link.

Report