View Full Version : Does Airbus flight computers run under Win NT??
I heard this rumor at work but just can´t belive it!!
I´ll never get onboard an airbus flight again...
// DLM :-(
12-06-2001, 03:52 PM
Can't confirm, but if it was true, you should be fine. If it was Win95, you'd have problems. :)
And what makes you think Boeing flight computers don't?
>I heard this rumor at work but just can´t belive it!! I´ll never get onboard an airbus flight again...
Depending on what you do, NT is pretty stable. 3.51 was the best combination of server stability and ease of use I've seen. It's been downhill from there, but I reboot my NT workstation every 2 months or so. The servers can go 3-6 months.
12-06-2001, 10:59 PM
I help maintain over 500 NT 4.0/W2k servers, 200 of them are NT 4.0, and most have been running for over 10 months without a reboot. We had one NT 4.0 server that went for 16 months without a reboot.
12-06-2001, 11:15 PM
Gives a whole new meaning to the "blue screen of death."
"Your aircraft has performed an illegal operation and will be shut down."
Okay guy´s you´ve made me feel a lot safer now (didn´t know NT was THAT stable).
Is there no one who can confirm this?
:-eek...:-hmmm...:-lol :-lol :-lol
12-07-2001, 01:34 PM
LOL@Jeff. Good one :-)
I did a search but couldn't find anything. The only thing I found was that Airbus Industrie uses NT and UNIX for software development, but then again, that's what all companies use.
12-07-2001, 02:07 PM
I seriously doubt ANY airline systems run an (even heavily modified) off-the-shelf OS.
I would imagine that flight control computers on the Airbus craft are practically 100% self-designed or independant systems. It may have some code snippits similar to NT or Linux/Unix, but more than likely its their own creation.
Wouldn't you think Microsoft or some other software developer would use that as a bragging tool?
"Look! Our stuff is so stable, it keeps airplanes in the air!"
Perhaps this is where Billy Gates is taking FS... Using the FS series as a jumping off point to develop integrated software for airliners. Umm, not. ;-)
12-07-2001, 02:30 PM
If that happened, they'll need to add Ctrl, Alt and Del keys to the cockpit.:)
12-07-2001, 04:54 PM
>If that happened, they'll need to
>add Ctrl, Alt and Del
>keys to the cockpit.:)
They have those in most fighters. They are called "eject levers" :).
A UAL A-319 I was on board from ATL-LAX basically had to be shut down and "rebooted" at the gate before we could push back.
That was about as close as we've come to the BSOD. It was the only time I've seen a plane have to shut down and boot back up to reset something.
12-08-2001, 03:04 AM
No, just imagine the faces on the 500 passengers in the back of that A380 when their TV screens display "Your airplane has performed an illegal operation and will be shut down". 500 ejection handles? Or solid 3 foot titanium cockpit doors?
WestJet Virtual Airlines
12-08-2001, 07:13 AM
Even if it does, the certification process is so rigorous that I wouldn't worry about flying their stuff.
Besides, I doubt that they use software that sophisticated. Despite the seemingly complexity of an aircraft like the A340 or 777, they don't require all that much computer sophistication to do what they have to do.
The software and OSs necessary to run these aircraft can be made very simple and relatively bulletproof.
Look at what the Shuttle uses to go into and return from earth orbit. Archaic by current desktop standards.
12-09-2001, 02:56 AM
True, but computers still crash, whether it be Boeing or Airbus.
WestJet Virtual Airlines
12-10-2001, 12:51 AM
One of the early A320's crashed because of software bugs... the A320 was by far the most computer-controlled plane in existence at that time and I guess they didn't wring out all the problems. After that, though, they haven't had any issues.
IN JUNE, a new plane hits the American skies. Northwest Airlines will become
the first U.S. carrier to take delivery of the European Airbus A320 -- the most
advanced passenger aircraft in the world, and already one of the most
controversial. In use since last May by British Airways and Air France, the
medium-sized 150-seat twin-engine jet is the first airliner to have every
function, from flight controls to toilet operation, directed by computer.
On June 26, 1988, two days after the third A320 went into service, it
crashed while performing a low-level pass at a French air show. A woman and two
children on board were killed. An investigation blamed the accident on pilot
error, but the pilot faulted a number of factors including the aircraft's
computers for providing incorrect altitude information. (The pilot, a senior
Air France captain, was subsequently dismissed.) Since then, various unsettling
reports have appeared in the European press, regarding: engines unexpectedly
throttling up on final approach; inaccurate altimeter readings; sudden power
loss prior to landing; steering problems while taxiing.
LAST EDITED ON Dec-10-01 AT 01:46AM (EDT)[p].
12-10-2001, 02:56 PM
Gee, not again... :-roll
I think you have been provided with inadequate sources!
Consider this for a second: Imagine that an aircraft, be it an airliner or a Jodel, has been placed in a situation when the pilot tried to fly out of the trap, but doing so was beyond the capabilities of the aircraft. How often do you think the pilot claims "gee, there must have been something wrong with the systems, I firewalled the engines but they didn't respond as fast as they should have"? Flight safety is a special interest of mine, and I have read literally hundreds of occurence reports during the years. I have never seen an occasion when the pilot did not blame the systems in such a situation, at least in the initial post-crash interviews. It is a perfectly natural, voluntary or involuntary, psychological defence mechanism, which is to be expected in such cases. If the pilot is then charged with a crime (I think the US translation of the charges would be "involuntary manslaughter" in this case), it makes a lot of sense to stick with that claim.
That the investigation "blamed the accident on pilot error" is a gross oversimplification on the behalf of the journalist. No accident investigation board ever blames anything on "pilot error"; journalists do that. Human errors play a part in each and every accident, but they don't cause airliner accidents. The questions to be answered are what caused the humans involved to commit these errors, and why were there inadequate defences in place to trap these errors? Blaming an accident on human error is just substituting one mystery for another. Even the criminal investigation put the blame on several individuals beside the pilots.
The situation is slightly different in GA accidents though. In those cases, it is well known that the system is not configured to prevent or trap all human errors. Thus, a GA crash might be a failure of the humans (pilot and others) involved, rather than a failure of the system itself.
The myth of the computers flying that A320 into the forrest is so well rooted that I doubt it will ever go away... And it is a convenient story too, really simple to grasp and "plausible" if you don't know the detailed circumstances of the occurence. The only problem with the story is that it is erroneous.
12-10-2001, 03:13 PM
Good call. Thanks for the clarification.:)
12-11-2001, 02:17 PM
hej if they told me that sitting in my seat, "Ladies and gentlemen due to a memory allocation error in the flight OS we have to reboot the plane " i would be the first one banging on the door to get out !!!! :-eek
12-14-2001, 03:36 PM
The crash of that Baby Airbus is not a myth. The aircraft would not allow the pilot to override it and it did fly the airplane into the trees. That was due to some very unusual circumstances that centered around the fact that the aircraft was being flown on a demonstration and the computer was actually trying to keep the pilot from doing something that would cause a crash.
That is why they have test flights. The real problem was that the configuration hadn't been tested to determine what the computer might do if the pilot attempted to execute a lowspeed go around with full flaps, ya ya ya. The next problem was putting pax on an aircraft and flying it outside of its tested envelope.
The A320 is my favorite medium airliner. I love the thing. In fact I just got off one in Piuttburgh three hours ago. It is smooth, robust and very well designed. But understand that when they crashed the airplane it was still very young technology and technology that was unrefined. To that end the airplane did what it was programmed to do and so did the pilot. The problem was that the two pathways were opposed.
12-19-2001, 09:00 AM
Sorry, I should have replied earlier, but my internet connection has been dead for a few days...
Todd, that is interesting, since it contradicts, among other sources, the official accident investigation, the legal investigation, Macarthur Job's excellent book, and what you generally find in those sources who choose not to put forward the various conspiracy theories... I suppose you have a decent source for your statements?
At the point when the pilots applied TOGA power to climb out, the basic climb performance of the aircraft did not allow it to climb over the forrest. This was not due to any failure on the part of the computers, but rather because the pilots flew the fly-past at an altitude lower than the surrounding trees, at the minimum flying speed (where the aircraft has to accelerate to transition into a climb), and discovered this condition too late. This is according to the official accident report, which goes on to explain in detail why and how the pilots (unintentionally) put the aircraft in this situation. It is true, however, that the computers would override any elevator nose up command in this situation, since such a command in these circumstances would instantly cause a stall. Maybe that is where the confusion arises?
The conspiracy theories arise from the notion that there is something inconsistent with the official report, typically by pointing out that the pilots blamed the aircraft for the crash. That was the point I was trying to make in the first post.
There are still some "issues" with the Airbus' fly-by-wire system, but those are not relevant in this case. These issues are typically due to system characteristics designed to prevent major dangers (e.g. stall) causing minor disturbances (e.g. the aircraft suddenly refusing to flare during landings in very gusty conditions with windshear). To the best of my knowledge, no significant changes were made to the flight control system as a result of the Habsheim accident.
Btw, anyones personal, subjective opinion about Airbus as a company is obviously beside the point, and I think we agree in that respect.
My experience of WinNT is good - it rarely fails :) On the other hand, my experience of Win98 is very different. If they used Win98 for A320s........ I think they would have incidents every day :-lol Only kidding :)
A fan of FS2002 and FS98
12-19-2001, 10:06 PM
This is exactly what I said. The computer understood the aircraft to be in a position to land and acted accordingly to keep the aircraft from stalling as the pilots attempted to pitch up and go around.
AS I said, the aircraft had not been flight tested like that before and the computer merely did what it was programmed to do.
You can cite whatever report you want, I am probably familiar with them and I agree that the computer was not to blame. However, as a real world pilot, I prefer to have the #####do what I want it to and not what it wants to when I want it to do something NOW. That means that the pilots should always have command override of the computer in such a way that hitting the override switch reverts the FBW system to a direct input interface, throttles, stick, rudders everything.
I have good reason for wanting this. When Air Canada found one of its 767s on an abandoned runway in Canada and had no real idea how it could have gotten there, they found that the pilot had a very good explanation (I paraphrase); it ran out of gas and became a glider, so I flew it like a glider.
After reports found that Boeing didn't think you could slip a 767. But it was quite apparant from both the flight crew and ground witnesses that a 767 will slip very nicely when commanded to by an experienced pilot.
So understand that while I love the Airbus A319-321 series of aircraft and the concept of fly by wire in general for what it will do to augment flight performance, I am very guarded about systems that do not allow a complete reversion to "analog" flight inputs by the pilot when called for.
The A320 demonstrator flew into the trees at Habsheim because the #####was trying to do what it was programmed to do and the pilot continued to attempt something that the #####s control system would not allow to be done. Of course with all of the cameras, and all of us have seen that clip by now, the first thing AI would do is hammer the pilots and defend its system. But the fact remains that the #####flew flat the length of the field and sailed right through the trees for lack of a 50 foot altitude change. 50 feet. I am here to tell you that when pushed to full power, even with everything hanging out, that airbus should have been very capable of missing the trees, but it didn't because when called to do so, it refused to obey a flight control input that its logic determined would place the aircraft in an unsafe configuration.
That or the #####was grossly underpowered. Either way, there is a problem that AI didn't want to admit and since we both know that CFM56-5 engines have a lot of power for the application, it makes one wonder just what else could have been wrong there.
Now Bjorn, you seem to be very impressed by official reports, so why don't you read this
and then when you are done come back and we can discuss the new findings of A320 tail attachment points delaminating much like those in a recent American Airlines Accident. You can also tell me why the French would allow an experienced Captain to be jailed for manslaughter because he did what he was told to do. You might also tell me what the heck a Mirage fighter was doing shadowing a TU-144 at the Paris airshow while it was on a demonstration flight. We can talk conspiracies, but I warn you AI is largely subsidized by the Government of France and since the French Government also conveniently controls the courts... ...well, I'll let you draw your own conclusions.
12-20-2001, 07:11 AM
>hej if they told me that
>sitting in my seat, "Ladies
>and gentlemen due to a
>memory allocation error in the
>flight OS we have to
>reboot the plane " i
>would be the first one
>banging on the door to
>get out !!!! :-eek
Imagine the scene:
Captain comes out of locked cockpit door, worried look on his face...
"Ladies & Gentlemen, can everyone switch their laptops ON... we need the computing power."
Oh what fun!
12-20-2001, 07:48 AM
Of course I have read the airdisaster.com version (yes, I know they didn't make it up themselves) of the story. I think it is a very interesting story, and I am rather impressed by it, from a propagandistic point of view. They mix half-truths, misleading "facts" brought out of their contest, and appeals to "common sense" in a rather expert way. However, how that version can convince anyone who has carefully read both the airdisaster.com version and the official version is beyond me.
The article you mention focus basically on two "facts":
1. The captain's version of the sequence of events.
2. The percieved inconsistencies regarding the DFDR.
This two main factors are then backed up by twisting other "facts" to fit into the theory.
I dealt with point 1 in my first post. It is worth reiterating that the pilots in this case were charged with a crime (something I highly disapprove of, in the name of flight safety), which might explain why the pilots were unusually persistent in blaming the aircraft. The pilots usually change their minds when they get the information from the investigation.
Point 2 is interesting. The authors do something really neat here: Already the second paragraph claims that "Since May 1998, it is proven that the Flight Data Recorder was switched after the accident". Great, now we know that to be true, we only have to prove it. If you do it the other way around, and look at the "proofs" first, it is not quite as easy to reach that "obvious" conclusion... The fact that the black boxes were in the hands of the DGAC rather than the police does not necessarily mean a thing; there are often disputes between the police and the accident investigators regarding who is "most" in charge of the investigations. The reasons for the DFDR shutting down prematurely is dealt with in the official report (The DFDR shut down when its power cables were severed in the landing gear bay region, due to the aircraft impacting trees. The final impact with terrain occured four seconds later. The board suggested that DFDR power supply cables should be routed differently in future designs).
Another example of the reasoning in that article:
"OEB 19/1 (May 1988): Engine Acceleration Deficiency at Low Altitude. This means that it was already known before the accident that the engines sometimes did not respond normally to the pilot's commands on the Airbus A320. However Air France did not inform their pilots about this anomaly. After the Habsheim accident, the engines have been modified (OEB 19/2, August 1988)."
Interesting. However, the official investigation showed this not to be a factor in this accident. Now, why did airdisaster.com not bother to explain that? They do not even claim that the accident report was wrong in that respect; they simply ignore it. If you didn't already know that the engines did respond properly in this case, OEB 19/1 seems to explain the (nonexistent) slow response of the engines. However, to an informed reader, it is simply an out-of-contest statement with no bearing whatsoever on this accident.
Now to some of the things you said, Todd:
"This is exactly what I said. The computer understood the aircraft to be in a position to land and acted accordingly to keep the aircraft from stalling as the pilots attempted to pitch up and go around."
No, it understood the aircraft to be in a position where the available lift was not enough to accomodate the load factor necessary to transition into a climb. You seem to forget that the computers were actually right in this respect. The aircraft had to accelerate before it could climb. The pilots knew this as well; they critisised the engines for not responding fast enough, not the fly-by-wire system for not pitching up. A manual reversion capability would have meant nothing here; the pilots could not have made the aircraft climb anymore than the computers could.
"AS I said, the aircraft had not been flight tested like that before and the computer merely did what it was programmed to do." Are you saying the the aircraft had not been flight tested in a situation where a rejected landing is required from a very low energy state? I find that extremely hard to believe (I don't say I won't believe it, but I'd need a very credible source...)
"The A320 demonstrator flew into the trees at Habsheim because the #####was trying to do what it was programmed to do and the pilot continued to attempt something that the #####s control system would not allow to be done."
That is a very strange statement. Even airdisater.com claims that the engine controls didn't produce the required response. You seem to claim something entirely different, namely that the fly-by-wire system didn't allow the aircraft to climb, yet without providing any source? The A320 is a conventional airframe with (at the time) unconventional control systems. For an aircraft to climb, it needs spare energy (excess speed) to convert into altitude, or an influx of energy from the engines to generate a rate of climb. No computers can change that.
Btw, you do realize that it was not a demonstrator aircraft on a test flight, but rather a production aircraft already delivered to the airline, which crashed in Habsheim?
"I am here to tell you that when pushed to full power, even with everything hanging out, that airbus should have been very capable of missing the trees, but it didn't because when called to do so, it refused to obey a flight control input that its logic determined would place the aircraft in an unsafe configuration.
That or the #####was grossly underpowered. Either way, there is a problem that AI didn't want to admit and since we both know that CFM56-5 engines have a lot of power for the application, it makes one wonder just what else could have been wrong there."
But Todd, it is so very simple: The engines were spooled down to idle power, since the pilots did not have time to stabilize the "approach" for the overflight. The aircraft was still descending and decellerating as it overflew the airstrip. This unstabilized approach is the key to the whole event. The pilots aimed to perform the flyover at 100 ft; yet, at 100 ft, the aircraft was still descending at 600 fpm with engines at flight idle. When the captain flared, the aircraft leveled out at only 30 ft, still with engines at flight idle. When the pilots discovered the trees, they ordered TOGA power, and the engines spun up and began to deliver thrust according to their specified performance - only too late to transition into a climb before impacting the trees. I tell you, by the time the pilots requsted TOGA power, it was already too late to avoid the accident. The crash had effectely already "happened", before the events when you and airdisaster.com claim that the computers "malfunctioned" (by reacting as designed, but according to "faulty" design specifications).
"You can also tell me why the French would allow an experienced Captain to be jailed for manslaughter because he did what he was told to do."
He didn't. He was not told how to perform the overflight. He was required by regulations to perform it 170 ft AGL (but the regulations were in practise not enforced). He intended to perfom it at 100 ft AGL, in stabilized flight. He actually and unintentionally performed it at 30 ft AGL, in unstabilized flight. There you have your answer.
"...well, I'll let you draw your own conclusions."
I conclude that you don't love France very much. Who cares?
12-20-2001, 08:12 AM
Some more infos about the AF A320 thing:
The Black Boxes
The Black Boxes (the DFDR and the CVR), major pieces of evidence, have been out of control of the investigating court at Mulhouse for 10 days. The CVR (Cockpit Voice Recorder) records the pilots' voices. The Digital Flight Data Recorder (DFDR) records the flight parameters, for example the altitude, speed, acceleration/deceleration, engine speed etc. According to the French Penal Procedure the police should have confiscated the black boxes immediately after the accident for further examination by independent experts. Instead the black boxes have been illegitimately in possession of the DGAC (Direction Génerale de l'Aviation Civile) from June 26 (the day of the accident) to July 6, when Germain Sengelin, investigating magistrate at Mulhouse, had ordered their confiscation.
The Black Boxes from which the official report has been made show a series of anomalies, which has led a lot of critical people since 1988 to call in question their authenticity:
The black boxes have been physically opened, the magnetic tape has been cut. Normally you put the black boxes into a reading machine without opening them - the same way you read a cassette in a video recorder.
8 seconds are missing in the recording, 4 seconds are missing just before the impact. That means that the DFDR would have stopped accidentally just before the impact.
The DFDR and the CVR are 4 seconds out of synchronization during the last part of the recording.
There is no indication of longitudinal deceleration at the impact. This might be expected in a collision with a mountain, but in Habsheim the recorders should have been able to operate until the aircraft disintegrated. Any crash which could be survived by all but 3 passengers should not have caused an abrupt stop in the DFDR recording.
Due to these anomalies, and the fact that the Black Boxes were in the hands of the DGAC, it has always been supposed, and is finally proven since May 1998, that the Flight Data Recorder confiscated on July 5 from the DGAC is NOT the one which was taken from the aircraft after the crash.
LAST EDITED ON Dec-20-01 AT 06:44PM (EDT)[p]Since 1990 I have found this whole incident fascinating - this was the year that my Aviation interest began. I haven't fully made up my mind as to the cause, and I will look into it again :)
If Michel Asseline is in prison for nothing... that would be a terrible shame, but I am not blaming Airbus. Pilot error and "limited FBW testing + Radar Altimeter error" are equally plausible (IMHO).
A fan of FS2002 and FS98
12-20-2001, 09:07 PM
Just a little comment on the software engineering aspects:
I believe that for safety critical software, literature indicates that the probability of it failing is 1 in 10^9. In other words, the expected value (or average) of it failing is once in 10^9 hours.
I remember reading that to ensure this, we will need to test the software for 100000 years. Even after testing it for so long, there's really no guarantee.
However, in order to ensure the quality criteria for the software is satisfied, proper reqirement analysis, SW development and testing process must be met. However, this is often not the case even with high-profile projects. A classic case of such failure is the Ariane 5.
:-jumpy :-wave :-jumpy :-wave :-jumpy :-wave :-jumpy :-wave :-jumpy :-wave
12-21-2001, 08:02 PM
LAST EDITED ON Dec-21-01 AT 08:14PM (EDT)[p]Bjorn:
Interesting. I take it you happen to be a multi-thousand hour ATP and have an in depth psychological understanding of pilots and their behavior.
Truth is, that I have watched that video tape many times, dealt with the French and lived in France and by the way, I happen to be a Commercial Pilot with some fair number of hours flying engines and airframes that require attention and forethought in terms of energy states. Most notably this is the case in helicopters; which I happen to fly on a regular basis.
Now my feelings about Air France are irrelevant, my feelings of how pilots behave and how aircraft perform are completely relevant.
You are trying to tell me that an experienced air crew purposely placed an aircraft that they had familiarity with in an unteneable situation with passengers aboard? After receiving appropriate training and type ratings? Come on. They knew the airplane, they knew what it could do and they had people on board.
Now the odd duck who endangers passengers is not a novel concept as a KLM pilot demonstrated at Teneriffe in his 747. AS well there have been several other notable incidents in which pilots of commercial airliners have done really stupid or ignorant things that have killed a lot of people and wrecked airplanes.
That video tape clearly shows the airplane in stable, level flight for several thousand feet of runway length, surely enough time for the crew to push full power and start a climb of a few 10s of feet. They didn't see the trees? Or notice that they were there? It was a perfect contrast sky and I submit to you that the airplane flew a perfectly level path right into the forest.
Had it been a 737 would the same have happened? I doubt it. The throttles go forward, the engines start to spool up but begin generating thrust and the judicious captain starts milking up pitch into the system and squeaks his airplane over the trees. Fact or fiction? I don't know until we test it, but I do klnow that when a computer decides when and if IT will increase power and by how much, well, the pilot becomes a passenger of some degree.
Nevertheless, my entire point, aside from the fact that I do not, nor will ever, put anything past the French Government where their interests are concerned, including the horrible idea of shadowing TU-144s with a rece Mirage and likely causing the crash of that aircraft at Paris; my entire point remains that I do not like and have never liked and still believe that computer limited flight envelopes without a manual override option is a very bad idea.
Now we can argue angels on the head of a pin type of things, but I am here to tell you that as a real pilot, with real experience in multiengine turbine powered aircraft, I am siding with the pilots of the Habesheim crash. I think the design and programming parameters created a situation in which the pilots found themselves unable to salvage the flyby.
I am constantly reminded that everytime a plane goes down, the speculation ultimately goes to the pilots failure to control or manage the airplane; well, pal, sometimes the airplane is at fault. Sort of like when Airbus was finally prompted to put a command override switch into their aircraft so that only one pilot would be inputing control data off the sticks instead of the computer trying to differentiate between right and left side of the cockpits.
So you can believe your propaganda and I will believe mine. Knowing how much France has invested in AI and how powerful their sense of national pride is, especially when the fly by wire concept was being introduced and everything was riding on it, I think the programmers screwed up and I think that if the pilots could have flown the airplane as they wanted to they would have salvaged that fly by.
It takes years of time and training to become an ATP, years of simulator training and line checks. You don't find too many idiots captaining airliners and bravado amongst ATPs almost always evaporates when their are pax on board. In fact the failure rate in terms of fatality causing errors made amongst airline pilots is six standard deviations from the mean. That means that the error rate is .0004% as measured by errors resulting in fatality against total numbers of flights. That happens to be the highest performance mark in any human endeavor.
SO, knowing the French, being a pilot and having read and viewed the evidence, my vote goes to the pilots and my scorn goes to AI for not stepping up and taking the hit.
Take Care, you are right, who cares? And by the way, as long as they continue to operate Boeing Products, I love Air France.
12-22-2001, 06:02 AM
We are both armchair quarterbacks here. You are a pilot, I am something else, and neither of us are professional accident investigators. You are as much of an amateur as I am ( what I am is of course irrelevant).
You are right, it would not have happened in a 737. Nobody would have tried to fly a 737 the way the french pilots tried to fly that A320 (and the pilot's overconfidence in the aircraft was also pointed out in the investigation). They were at 30 ft, 121 kts with engines at flight idle (29% N1), having manually overridden the alpha protection in the fly-by-wire system, which would not have allowed the aircraft to be put in this position. You can't possibly see from a video that an aircraft is continously decelerating, can you? The aircraft struck the trees with the tail four seconds after TOGA power was applied from that condition. N1 was 83-84 % at the time of impact, reaching 91 % 0.6 seconds later; i.e., the engines begin to deliver considerable thrust only the last second before impact with the trees. Get the picture now?
The reasons for why the pilots did this is the hardest part to understand, and you are right that it does take some knowledge of human behavior (professional pilots are humans...) to understand it.
But then again, who cares... :-roll
12-23-2001, 11:40 AM
I hate to tell you this, but one of your assumptions is wrong. I'll let you decide which one it is. The hint I'll give you is that I have a modicum of experience with aircraft accidents. Mind you, just a tiny little bit.
I want to see the data from the FDR from THE airplane. That may or may not be what was presented in court.
Mind you, I think your analysis is thoughful and quite objective, but unless you work as a design engineer for AI on the A320 and have actually examined the FDR from that A320, or work for the principal investigating body on that crash, then you and I are both pulling things out of second or third hand sources.
As far as who cares; I think it obvious that you and I both care. The question is, does anyone else?
PS: After we grind this into the dirt, let';s discuss the real reason why TWA 800 went down.
12-24-2001, 07:18 AM
If one of those assumptions were wrong, I do owe you an apology... :-shy
You are right of course; everything I say is based on other people's description of the events. If the FDR was replaced, nothing I said makes any sense whatever...
So was it replaced? I won't place a bet either way! ;-)
"PS: After we grind this into the dirt, let';s discuss the real reason why TWA 800 went down."
I guess we are there already! :-lol And the TWA crash is so boring...
12-24-2001, 11:45 AM
Not when you realize that you will never see one side of that wreck. It is always filmed from only one angle. Don't you find it terribly funny that after millions of flight hours that suddenly a 747 would just explode in mid-air.
That ought to stir the pot.
About the time that we get to find out who killed Kennedy we'll get to know when the Surface to Air missile that dropped that 747 was manufactured.
06-25-2002, 11:43 PM
>Gives a whole new meaning to
>the "blue screen of death."
>"Your aircraft has performed an illegal
>operation and will be shut
Add this for the Windows XP Users:
An error has occured in A380MAIN.DLL. Would you like to report this to Airbus?
To view what is in the report, click here.
Send Report Don't Send Report
06-25-2002, 11:49 PM
Acutally, it could be convenient it is offered to automatically file an ASRS report!
06-26-2002, 03:25 AM
I remember on a 757 just getting ready to push back, it pushed back, then we heard a clunk and all the power was out. They had to push us back and repower us, and reset the computers. It sounds the same, but I think it was electrical.
Keep on Flyin'!
AMD Thunderbird 1.4 ghz
NVidia GeForce 2 MX 400 32 MB
Sound Blaster PCI 128
512 MB RAM
Good frame rates!
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