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Investigators Suspect Computers Doomed Air France Jet
DesScorp writes "Investigators working with the wreckage of Air France flight 447 believe the aircraft suffered cascading system failures with the on-board computers, eliminating the automation the aircraft needed to stay aloft. 'Relying on backup instruments, the Air France pilots apparently struggled to restart flight-management computers even as their plane may have begun breaking up from excessive speed,' reports the Wall Street Journal. Computer malfunctions may not be an isolated incident on the Airbus A330, as the NTSB is now investigating two other flights 'in which airspeed and altitude indications in the cockpits of Airbus A330 aircraft may have malfunctioned.'"
Second, the US announcement of the two computer failures, neither of which caused an accident, presumably has nothing at all to do with Boeing's recent embarrassment over continuing delays and cancellations to the Dreamliner, and a desire to damage Airbus?
From scarped cliff or quarried stone she cries "A thousand types are gone, I care for nothing, no not one."
...the way aerospace (life critical and specialized or specific field oriented) software is created, it is highly bug free, quite the opposite of feature creep bloat you see everywhere else, but even at the code level there is avoidance of function calls that can introduce another level of abstraction and complexity and contribute to bugs and failure. It is in this way that using the process of elimination we can come to some conclusions about where error is or can most certainly exist, philosophy.
On a hardware level, we have redundant backups and check system....
As such there is one area that neither software nor hardware has but only as a secondary or implimentation of, position.
Human error in concepts, beliefs, philosophies, abstraction definition variation, etc... That which exist before the hardware and software and often what hardware and software creation is inspired by, directed by, guide lined by, etc..
If the philosophy base is wrong then its limitations will manifest through the software and hardware created under such a philosophy and eventually show the limitations, via failure to perform.
There are plenty examples of human philosophy errors, such as how it wasn't until the early 1990's that the Catholic Church exonerated Galileo over his observation the earth revolved around the sun.
The Atlanta Centennial park bombing where the 911 system failed because no-one gave the park an address..... or is the philosophy of programming a 911 system to require an address the error? Or is it a good thing that all things needing 911 are at an address?
My pet peeve of the computer industry, the button on the front of the computer marked with a 0 & 1 symbol(s), yet over engineering has resulted in the meaning of those symbols to be more than "off & on" and this went further in removing the hard on off switch so that when the software based power switch failed, you have to physically unplug the computer from the wall, or take teh battery out.
The correct philosophy for such a switch would be a multi position switch, which the consumer doesn't have to know more than is obvious... And ultimately the motivating philosophy behind the software switch is that of creating an OS that needs a shutdown sequence and time for it. When you think of this "0&1" switch, what better representation of distorting the most basic and fundamental concept of computers with overcomplexifabulocation can there possible be?
Software and hardware is not where the error lies in this Air France tragedy, even if there is failure or limitations found there in hardware and software, but the failure is in not providing a manual override. And if the technology has been made to complex for manual control.... then let grandma crawl under the desk to unplug the damn computer....shut it down until the real problem is fixed.
BTW, due to the competitive commercial nature of aerospace software development tools, there is a level of incompatibility between them and as such there is also motive for playing the lockin game regardless of any "unforseen" risk to others. Perhaps there is a place for open source software here!!!
Don't bow down to the stone image (Stone = computer hardware - Image = software) of the beast of man, for the beast is error prone and his image can be no better. Instead take a closer look at the code.... with many eyes.....
Pitot tubes were invented in the 1700s by the French Engineer Henry Pitot and later modified for airspeed measurements. They are also used to measure aerodynamic speed in Formula racing cars too among other uses. Here is a comprehensive article following the crash investigation that is informative with photographs and the timeline of theories.
I read both the articles posted. They do not qualify as the best investigation reports. They seem to be building "What if" scenarios from all data that is available. Other A330 failures (no recent crashes reported) and Other places where ice in Pitot tubes led to failure (The Wikipedia article has a lot of information on this and planes which had problems notably, the X31.) The investigators are clearly under pressure to say what they have found and they are unable to report "nothing" to the press. With no luck in recovering the Black Box, the investigators (like they talk about Pilots not good at flying aircraft without the aid of in-flight safety systems) have to do it the old forensic way (reminds me of Crichton's Airframe). That is going to take time and the press, the Aircraft companies using A330s are impatient to know why.
Clearly no recent theory has come close to deducing the true reason for the crash. As I remember the first news item that appeared on the AF447 was that the plane "vanished" from Radar and was sought for by the Brazilian Air Force before the crash site was positively identified. The last exchanges between the Pilot and the Aircraft tower followed by an automated message from the aircraft remain the main clues apart from the debris in this horrific accident.
No Greater Friend, No Greater Enemy! (Lucius Cornelius Sulla)
There are a couple of aspects about the A330 problems that amaze me:
1. How can an airplane be allowed to carry passengers when the margin to airframe disintegration is so narrow? I can understand falling out of the sky if it stalls, but to be able to tear the airplane apart in level flight? What happened to margin of safety in airframe construction -- or is that whole concept now obsolete?
2. If the airplane can send fault messages home, why don't blackbox data streams get sent as well? At least that way there would be some situation info available as opposed to none.
3. In some ways reliance on flight computers is like reliance on spreadsheets or calculators -- if you do not understand what is going on and are not capable of doing it yourself then you cannot tell if the software is correct. Essentially, if the computer says it is so then it is, and you either survive or not.
This is why I really want any airplane I'm flying to LISTEN to me, not argue with me... At no point should a computer be able to override pilot input. Also, i want a solid mechanical link between the controls I'm pushing on and the control surfaces on the wings... That way, even if EVERY computer on the plane dies, I can still control the damn thing...
And yes IAAAP... (I Am An Airline Pilot)
But can't land your plane in a river if it'll save your life.
Nah. This is all about designing to handle faults you can imagine, and failing to handle faults you can't. Imagining roll-over or stalls are easy. Imagining everything that could go wrong in a wind storm, probably not so much.
Remember the DC-10 that crashed in IOWA? It took two guys trying to control it without hydraulics. Personally, given the choice of hydraulics OR electric motors, I would take electric motors. Electric is CHEAP AND SAFE to have redundant electrical lines. In addition, losing one, does not mean that you lose the whole aircraft like Walt Lux did in the AA dc-10 that crashed at O'hare. The problem with the Airbus is that Airbus designed the CPU to take control of the craft. If the pitot tubes are blocked, the sensor will think that the aircraft is moving at 0 knots and will DIVE IT. Since it still does not know the speed, it will continue to dive it faster and faster until stress ripped the plane apart. Sadly, this has happened on MULTIPLE issues with the plane, and had it all blamed on "PILOT ERROR". When this is done, I think that AA and several other companies will be suing the pants off Airbus for their design as well as hiding facts.
I prefer the "u" in honour as it seems to be missing these days.
In the case of AF447 the vertical stabilizer was recovered intact with the rudder still properly attached.
I'm not a coward by any name.
In this case, the black boxes have not been recovered
And at 26 days elapsed time since the crash, its pingers batteries are probably gone to the battery graveyard, never to be seen or heard from again. I doubt by now if it could be heard 100 yards away even by Alvin. One of the ways to save money is by not replacing those batteries on a fixed schedule. And I wouldn't be surprised to have the NTSB admit they can't find that maintenance log either.
I hate to say it, but the detective work to see what happened may well depend on similar instances the pilots managed to handle & restore control.
The comments so far re windows would seem to be a bit premature since even windows can have month + uptimes if the programs it is asked to run are clean. Flight certified software is generally tested till it can handle anything without a people killing failure.
That might surprise some to hear me say that since I'm a fairly famous anti-windows person, given that the only windows install here (XP on my laptop) was nuked and Mandriva-2009.1 installed a couple of months ago & everything else has been some flavor of linux since 1998.
The thing that burns me is that Airbus knows about the problem with the frozen pitot tubes, but didn't insist they be replaced with the retrofit kit at the first overnight stop. So CEO's did what CEO's do best, maximized profits by keeping the engines spooled up & flying. "This" was something that could be handled at scheduled maintenance times in their minds. The question about that for this flight is probably never going to be answered given the black box hasn't been found and likely won't be. But they have at least 2 other flights where only quick action by the pilots saved the day, & they should be acting on it as we read this, not waiting for the NTSB to pronounce guilt before they cut checks. That lack of action should be criminally prosecutable IMO.
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Cheers, Gene
"There are four boxes to be used in defense of liberty:
soap, ballot, jury, and ammo. Please use in that order."
-Ed Howdershelt (Author)