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Failed Avionics a Possible Cause of BA038 Crash 369

Muhammar writes "As you may have heard by now, both engines of the Boeing 777 aircraft flight BA038 suddenly cut off without warning at very low altitude and low speed during autopilot-assisted landing at Heathrow. A prompt reaction of the pilots prevented the stall and saved all lives aboard. The crash landing short of the runway tore off the landing gear on impact, and the fuselage plowed a long, deep gouge in the grass. With the investigation ongoing, the available information points to an electronic control problem as the most likely cause of the sudden engine power loss."
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Failed Avionics a Possible Cause of BA038 Crash

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  • Software? (Score:3, Interesting)

    by Marcion ( 876801 ) on Sunday January 20, 2008 @11:52AM (#22117018) Homepage Journal
    If it is a software problem, then expect more public scrutiny of software based machinery. Especially after the US Senate vs UK debacle over the source code for the new joint-combat fighter.
    • by Marcion ( 876801 )
      (wikipedia reference [wikipedia.org]) - those buying expensive technology projects increasingly want the source code too.
    • by Marcion ( 876801 )
      TFA: The 777 model, which entered commercial service in 1995, relies heavily on computers, so one area for examination is whether the software functioned properly.
    • by Technician ( 215283 ) on Sunday January 20, 2008 @12:24PM (#22117212)
      If it is a software problem, then expect more public scrutiny of software based machinery.

      That is not likely. More likely is they had a glitch from a strong RF field someplace. Knowing the timing, it is likely to be either a radar or other high power beam or a very near lower powered source such as a cell phone inside the farady cage. Very likely the radio source is from something like this; **RING** **RING** "Hi hon, we are landing now.. Oh no, somethings wrong.."
      • Re:Software? (Score:4, Interesting)

        That is not likely.
        Yes it is likely. We are expected to believe that a single consumer grade device caused the simultaneous failure of both engines? Or from high powered sources which the planes must be built and certified to withstand. Give me a break. A Computer/Hardware glitch is a far more plausible cause.

        That said, my paranoia meter says this could have been caused by some nut near the airfield with a HERF Gun [slashdot.org].
        • Re:Software? (Score:5, Informative)

          by badasscat ( 563442 ) <basscadet75NO@SPAMyahoo.com> on Sunday January 20, 2008 @02:39PM (#22118260)
          Yes it is likely. We are expected to believe that a single consumer grade device caused the simultaneous failure of both engines?

          You're right that it's more likely than RF interference. But neither is likely at all.

          A software glitch of this type (if that's what it was) has never happened in aviation history. Certainly not in the 10 year history of the 777, with more than 500 of them flying around the world, but not to any other type either.

          Also, the engines didn't "fail". The engines were running both before and after the stall (and yes, the aircraft did stall, despite what the article summary says). "Failure" and "failure to respond" are two different things.

          In some ways that's even more scary, because it rules out simple explanations like fuel exhaustion. It's one thing for engines to fail, quite another for them to simply ignore control inputs.
          • Re:Software? (Score:4, Informative)

            by TooMuchToDo ( 882796 ) on Sunday January 20, 2008 @05:00PM (#22119616)

            In some ways that's even more scary, because it rules out simple explanations like fuel exhaustion. It's one thing for engines to fail, quite another for them to simply ignore control inputs.

            Indeed. If I'm piloting a turbine engine aircraft, I much prefer for the engines to just fail then for them to ignore my commands. Fly-by-wire is pretty cool until the engines ignore your commands and you have no way to shut the fuel off to them.

          • Re:Software? (Score:4, Interesting)

            by TClevenger ( 252206 ) on Sunday January 20, 2008 @11:03PM (#22122540)
            A software glitch of this type (if that's what it was) has never happened in aviation history. Certainly not in the 10 year history of the 777, with more than 500 of them flying around the world, but not to any other type either.

            It's certainly not without precedent. No case of air/fuel mixture explosion was found in 747's until TWA 800 [wikipedia.org] in 1996, and 1,396 of those were built since the 747 started flying commercially in 1970.

          • Re:Software? (Score:4, Informative)

            by einhverfr ( 238914 ) <chris@travers.gmail@com> on Monday January 21, 2008 @12:38AM (#22123192) Homepage Journal
            I think a single software glitch is unlikely to be the cause of the failure. However, best guess at the moment is that the engine issues were software initiated.

            You can only mathematically prove that software is bug free given some basic assumptions about hardware performance. If those assumptions fail, then your bug-free software is now buggy because the hardware is buggy and it can't sort out valid from invalid information.

            TFA mentions another avionics glitch where a failed accelerometer caused a near accident on a 777 in Australia. The software inappropriately responded to the failure because the failure condition wasn't foreseen.

            Most likely the root cause is hardware-related, not software-related. For example, maybe water-based corrosion on some contacts somewhere where the seal was damaged, or a short circuit on some sensor somewhere else. The issue is that this may have triggered failure conditions that were not previously foreseen in the software design.

            The 777 has an impressive safety record. However incidents where, say, water gets into circuitry and causes problems, or some previously unforeseen failure situation arises, there will be problems.

            As for the "first of its kind" remark-- this is not the first software initiated problem in the 777 if indeed that is the case. It *is* however, the first 777 crash ever. Which ought to make one a little less inclined to question previously unforeseen problems.
          • Re: (Score:3, Informative)

            by adpsimpson ( 956630 )

            A software glitch of this type (if that's what it was) has never happened in aviation history. Certainly not in the 10 year history of the 777, with more than 500 of them flying around the world, but not to any other type either.

            IAAAE (I Am An Aeronautical Engineer) and to take serious issue with that statement.

            According to the Times today [timesonline.co.uk], there have been at least 2 reported computer 'glitches' on 777s in the last 3 years. One lowered the airspeed from 270 to 158 knots along with putting the a/c in a

          • Re:Software? (Score:4, Informative)

            by Alioth ( 221270 ) <no@spam> on Monday January 21, 2008 @07:21AM (#22125034) Journal
            I doubt the aircraft stalled: a large aircraft like a Boeing 777 will _not_ recover from a stall in 600 ft, and everyone would have been dead. If it stalled at all, it would have been just before touchdown while the crew were trying to arrest whatever sink rate they could before impact.

            As for fuel exhaustion - that was ruled out very quickly - plenty of fuel leaked from at least one breached fuel tank. It's the first thing the investigators would have done - look in the tanks and see if there was fuel. That doesn't rule out fuel STARVATION though - you can have plenty of fuel on board, but something stopping it from reaching the engines.
      • Re: (Score:3, Interesting)

        by Troed ( 102527 )
        or a very near lower powered source such as a cell phone inside the farady cage

        While already moderated funny, I'll just clarify that this is a myth. A more likely explanation for the cellphone ban on planes is due to the networks not being able to handle several hundred clients moving at 800km/h in view of tenths maybe hundreds of base stations.

      • Re:Software? (Score:5, Informative)

        by Anonymous Coward on Sunday January 20, 2008 @02:33PM (#22118196)
        If a cell phone can do this much damage, why the hell am I allowed to bring one (several even) on a plane?! These days, a swiss army knife will maybe get you as far as row 6 before people dogpile you, and they are confiscated. But a plane has easily 50 cell phones on it at any given time. If the only thing between me and engine failure are passengers dutifully following crew member instructions, then we are all screwed. So I am going to respectfully suggest that you are mistaken, because the alternative seems ludicrous.
    • Unlikely. The have several computer systems all doing the same thing, designed, written and built completely separately to each other. The plane then does whatever the majority of them say. In the unlikely event one happens to have a bug and gives the wrong command, the other systems disagree and outvote the buggy system.

      For the plane to actually fail because of a software bug, the majority of the systems would need to have exactly the same bug at exactly the same time. Given their source code is checked ve
      • Re: (Score:3, Funny)

        by TheLink ( 130905 )
        Well I hope they didn't outsource the coding to 5 different software companies in India who then in turn outsource it to the same subcontractor :).
      • by 0racle ( 667029 )
        I've heard [plala.jp] of this before somewhere.
      • Re:Software? (Score:4, Interesting)

        by AlecC ( 512609 ) <aleccawley@gmail.com> on Sunday January 20, 2008 @01:26PM (#22117642)
        Actually, they have given up creating multiple implementations of the code. There were only ever two implementations, scattered across several computers. However, when developing the systems for this very aircraft type, Boeing decided that they now have tools which can verify precisely that the software matches the specification, and where they actually need to put the effort in is in checking that the specification makes sense. Rather than wasting effort in having two teams implement implement the specification, and verify that using automated tools, you use the extra effort to look closely at the specification.
        • Re: (Score:3, Insightful)

          by PingXao ( 153057 )
          That sounds really dumb. Tools that can verify that software matches the specifications 100% in every case under every condition? For anything but the most rudimentary code I seriously doubt that. There was a relatively recent incident where a 777 gave warnings that it was going too fast and too slow, both at the same time. Attributed IIRC to a failed sensor and software not programmed to handle the error correctly. That blows the 100% software verification test suite right out of the water. If they r
          • Re:Software? (Score:5, Informative)

            by AlecC ( 512609 ) <aleccawley@gmail.com> on Sunday January 20, 2008 @04:13PM (#22119178)
            No - it shows that the specification did not define what should happen with out of range conditions. The use formal specification languages to define what they want the software to do, but it is precisely these sorts of unforeseen circumstances which show that the spec was wrong, and the code only did what was specified.
    • by Z00L00K ( 682162 )
      It sure seems to be some kind of glitch - either software or hardware.

      If the hardware weren't redundant then somebody has to be responsible for that and at least get a good kick in the ass. Probably at the economic department...

      A software glitch may be triggered by borderline limits exceeded and started a default mode in which the engines were shut down or at least put to idle mode. Since this was at an unfortunate position this was triggering an accident. At a higher altitude there would have been ampl

  • Errrrr.. (Score:5, Insightful)

    by Deekin_Scalesinger ( 755062 ) on Sunday January 20, 2008 @11:57AM (#22117042)
    A bit of FUD here I think - unless I read TFA wrong, the entire thing is under investigation and no one is saying anything for at least a month. The autopilot apparently sensed the need for more thrust and warned the pilots of this. It might be premature to say that a software problem is the likely cause of failure...
    • by Alien54 ( 180860 ) on Sunday January 20, 2008 @12:09PM (#22117100) Journal
      "It might be premature to say that a software problem is the likely cause of failure..."

      Unless it was running on an OS like Windows for Aircraft, "now with fewer crashes".

      Yes, I know it's all custom designed. But thinking about the infamous Windows for Warships [theregister.co.uk] I couldn't resist
    • Re: (Score:2, Interesting)

      by Thilo2 ( 214163 )
      You can be sure that the autopilot did not need to warn the pilot. Even a relatively unexperienced pilot will notice when
      a) The airplane drops below the glide path
      b) The airplane flies at too high of an angle of attack
      during landing.
    • Re:Errrrr.. (Score:5, Insightful)

      by einhverfr ( 238914 ) <chris@travers.gmail@com> on Sunday January 20, 2008 @01:08PM (#22117518) Homepage Journal
      Not so sure.

      I read a number of articles on it and:

      1) Avionics resulted in a near miss relating to a 777 a few months ago operated by Malaysian Airlines. The problem was a combination of a software bug and a dead sensor (i.e. the software didn't properly handle sensor errors and a sensor went dead).
      2) Despite this problem, the 777 still has an impressive safety record. Only one crash in the history of operating that aircraft and that didn't result in fatalities?

      In a plain like the 777 basically, you have three possibilities: human error, electronics failure, or mechanical failures. I think this case seems unlikely to be the result of other human or mechanical failures, so we are left with electronics issues and the primary suspect.

      I am guessing that the real lesson here is that nothing is infallible, but that the 777 is pretty-darn good.

      My suspicion is that we will eventually find that the 777 needs regular maintenance to portions of it which have not received as much attention in the past. It could be a similar issue to the MA failure-- a dead sensor sending information the software was not prepared to handle, it could be an electrical short circuit (for example, caused by water corrosian or even condensation) as we saw recently with the ISS. The point is that only now, thirteen years after the planes entered operation, we are running into these problems. I don't think that software alone could have caused the problem. More likely it is a combination ofhardware failure triggering bugs in software.
      • Re:Errrrr.. (Score:5, Insightful)

        by SL Baur ( 19540 ) <steve@xemacs.org> on Sunday January 20, 2008 @03:22PM (#22118696) Homepage Journal

        I am guessing that the real lesson here is that nothing is infallible, but that the 777 is pretty-darn good.
        That's what I read out of it too. The track record remains and speaks for itself - those are damn good planes.

        They experienced a catastrophic failure losing both engines at low altitude where the plane has all the flight worthiness of a brick and nobody died.
    • by jhines ( 82154 ) <john@jhines.org> on Sunday January 20, 2008 @01:11PM (#22117534) Homepage
      Given that the plane is heavily instrumented, available, and didn't burn, this should be a simpler case to examine. Hopefully, a lot can be learned. At least more than if it crashed and burned in a jungle, or into the ocean.
    • Re:Errrrr.. (Score:5, Informative)

      by Richard_at_work ( 517087 ) <richardpriceNO@SPAMgmail.com> on Sunday January 20, 2008 @03:19PM (#22118662)
      The current official initial report says the following -
      1. The autothrottle system commanded an increase in thrust from the engines which did not respond
      2. The autothrottle demanded further increases in thrust again with no results
      3. The PIC commanded an increase in thrust via movement of the throttles, with no result
      4. The aircraft slowed and subsequently lost height
      http://www.aaib.dft.gov.uk/latest_news/accident__heathrow_17_january_2008___initial_report.cfm [dft.gov.uk]

      For both engines to have not responded to either the autothrottle or manual throttle movements, we are looking at a software issue in either the FADEC or the EMC.
  • by Malevolent Tester ( 1201209 ) * on Sunday January 20, 2008 @12:04PM (#22117074) Journal
    They actually have a decent excuse for lost luggage for once.
  • by bradgoodman ( 964302 ) on Sunday January 20, 2008 @12:04PM (#22117078) Homepage
    No - I don't think so. The autothrusters responded properly, but they literally just move the throttle levers, to which the engines didn't respond.

    The pilots then manually increased throttle - to no avail.

    For both engines to malfunction like this at the same time greatly seems to point to a fuel delivery problem.

    This does not necessarily mean "running out of gas" - as a plane like this has multiple tanks, valves and pumps, all of which can be configured multiple different ways - which change during the flight.

    A simplistic example: they could have been running both engines off one tank - which went dry - though another was full - or both engines were being fed from a common fuel pump which failed, etc. These things *shouldn't* happen - but the investigation will tell...

    • For both engines to malfunction like this at the same time greatly seems to point to a fuel delivery problem.

      This does not necessarily mean "running out of gas" - as a plane like this has multiple tanks, valves and pumps, all of which can be configured multiple different ways - which change during the flight.

      Perhaps the electronics malfunctioned and stopped pumping the gas?
    • by s20451 ( 410424 ) on Sunday January 20, 2008 @12:13PM (#22117138) Journal
      In two other instances in large jets of engine failure by fuel starvation (Air Transat 236 and Air Canada 143), the failure of the engines was not simultaneous: one engine kept working for a few minutes longer than the other.

      The fact that the engines responded the same way, at the same time, strongly suggests a single point of failure in an electronic flight control system.
      • by AlecC ( 512609 )
        The didn't fail exactly at the same time: one was spinning and one not when it hit the ground.
    • by chuckymonkey ( 1059244 ) <(moc.liamg) (ta) (notrub.d.selrahc)> on Sunday January 20, 2008 @12:15PM (#22117150) Journal
      These things *shouldn't* happen - but the investigation will tell...


      Exactly why speculation as to the cause gets us nowhere. Pointing fingers and throwing blame about serves nothing, just like the guy above saying something about Iranians. We really should have something similar to a Godwin for Terrorist/Bush/Iranian bullshit that people post.
    • by DaveAtFraud ( 460127 ) on Sunday January 20, 2008 @12:23PM (#22117206) Homepage Journal

      No - I don't think so. The autothrusters responded properly, but they literally just move the throttle levers, to which the engines didn't respond.

      Just because the indicators in the cockpit show that the autothrusters were to provide more power doesn't mean the signal gets to the engines. There is a lot of wiring and other systems between the cockpit and the engine. On a "fly-by-wire" plane like the 777, even moving the throttle levers just sends a signal to a system that eventually gets to the engines. Bottom line is there are lots of lower level avionics systems that could have failed and the pilots would only see that the autothruster was supposed to provide more power and didn't.

      The question is, which on the various boxes along the way had a BSOD?

      Cheers,
      Dave

      • The right and left engines are controlled by different computers. The only single points of control are the pilot and a central engine control system. Thus in the absence of pilot error, the only single point of failure is that specific avionics system.

        Now the root fault may be due to some sensor or processing system failing and causing a cascade failure to other portions of the system. This sort of thing *has* happened in other 777's (an accelerometer failing in a way as to cause a cascade error into fl
    • by mpe ( 36238 )
      A simplistic example: they could have been running both engines off one tank - which went dry - though another was full - or both engines were being fed from a common fuel pump which failed, etc. These things *shouldn't* happen - but the investigation will tell...

      The design of a typical jet's fuel system means that you just cannot have engines running from the same tank. Each engine has it's own tank (in the case of a twin such as the 777 this is the entire wing tank). Fuel can be fed from other tanks int
    • From the article:

      On February 7, 2005, a Virgin Atlantic Airbus 340, flying from Hong Kong to Heathrow, was passing through Dutch airspace when, without warning, one of its four engines - the outer engine on the port wing - went dead.

      The crew quickly established from the Airbus's sophisticated displays that the amount of fuel contained in the inner tank, from which the engine was feeding, registered as "0". What they did not realise was that the automatic transfer system between the tanks had failed.

      The oute
  • Damnit! (Score:4, Funny)

    by DoofusOfDeath ( 636671 ) on Sunday January 20, 2008 @12:10PM (#22117118)
    Now we're all going to be forced to re-learn Ada!
  • by bananaendian ( 928499 ) on Sunday January 20, 2008 @12:16PM (#22117152) Homepage Journal

    With the investigation ongoing, the available information points to an electronic control problem as the most likely cause of the sudden engine power loss."

    What I've read is that the pilots observed a relatively gradual loss of power symmetrically on both engines. This tells me that I can rule out engine problems with FADEC and fuel. It all points to the auto-throttle. Autopilot tells where it wants the plane to go and autothrottle calculates how much throttle is needed. It then commands both engines FADECs via the bus system which is doubly redundant. What I'm thinking is that auto-throttle is supposed to be backed up, bypassed by a manual direct control to the engine FADECs from the cockpit throttle control?

    Any B777 avionics mechanics around - I only know military jets...

    • That damn signed integer strikes again ! http://games.slashdot.org/article.pl?sid=08/01/19/1321241 [slashdot.org]
    • There are so many things that could have gone wrong. The Bowden cable might have been loose. The fuel filter might have caught some dirt if the fuel tank was low. The idle air control might have failed due to a number of reasons, such as the failure of the air flow sensor-- note that the engines were basically idle on approach. I don't think it was the ECU, since they probably have a bunch of redundant ones.

      • The Bowden cable ... The fuel filter ... the fuel tank ... idle air control
        You're using a lot of singular nouns, considering it was a twin-engined plane.
    • by BlueStrat ( 756137 ) on Sunday January 20, 2008 @01:06PM (#22117494)
      Not a commercial aircraft airframe and powerplant mechanic, but I was a senior avionics technician for many years dealing with corporate and private jets.

      What I've read is that the pilots observed a relatively gradual loss of power symmetrically on both engines.

      Interesting. Do you have a link to the source for that? Not that I doubt you, just curious to parse it myself.

      This tells me that I can rule out engine problems with FADEC and fuel.

      FADEC, possibly, but fuel? It's quite possible there was either water or crud in the fuel, especially since the aircraft almost certainly took on fuel in China, and China seems to have had problems of late with products being adulterated in some form. The crud could cause blockages in the filters from the tank(s). The water would cause an increasingly-diluted fuel mixture to enter the engines as the level dropped which might also cause the gradual loss of power.

      The two most-likely culprits I would examine first are the discrete devices at either end of the control path that send the data and receive it at the other end, and the cables and connectors used to transmit the data.

      The next point I'd check would be the power supply that powers the electrical actuators that physically move the actual throttles in each engine. This supply would be separate from the power used for the electronics, as it would be a relatively high-current source. This might also be caused by cabling/connector problems.

      Aircraft tend to have many problems with cabling due to high vibration and multiple pinch-points and stress and vibration/abrasion at support points, as well as contact problems at connectors.

      Another very major problem is human error. In many cases the turn-to-lock type connectors are in very tight spaces, sometimes so much so that it may only be visible by a small mirror and flashlight held by the tech while he may be laying on his back or nearly standing on his head. I had a whole set of strange-looking pliers of different lengths and weird angles with curved padded jaws for just this purpose in my tool box, along with small hand-held extend-able flexible-tubing-mounted inspection mirrors and flashlights with the head on flexible tubing as well.

      It can be very hard to tell, given the above circumstances, if the locking sleeve on these aircraft instrumentation connectors had been twisted far enough to complete the lock. It doesn't take much imagination to see what could happen given time, vibration, and G-forces.

      Of course, these are just my rough guesses, and I don't have enough information to really make any informed statements.

      Cheers!

      Strat
    • Re: (Score:3, Informative)

      FADEC = Full Authority Digital Engine Control. On the Rolls Royce Trent 800 engine its called an Electronic Engine Control System (EECS).

      The article describes the EPR (Engine Pressure Ratio, a measure of the power output) as slowly decreasing in both engines at the same time. If thats true it doesn't sound like fuel starvation. One: the EPR would simply drop to zero, not tail off, and two: the engines are unlikely to both stop at the same time.

      There was a 767 that ran out of fuel over the Atlantic some time
  • by XMLsucks ( 993781 )
    I've read several summaries, such as this one, which state that the pilots did something to save the lives of the passengers. But I've never read a news article that provides the information that supports this claim. I'd like to read about what the pilots did to save the situation. Can anyone point out a news article that is actually coherent, and tells more than how many 777s are in service around the world?
    • by bradgoodman ( 964302 ) on Sunday January 20, 2008 @12:33PM (#22117274) Homepage

      The word "hero" is thrown around a lot these days...

      I believe what they meant, was that the pilots realized that things were going wrong, and the "normal" reaction would be to add thrust. When they realized that they couldn't add thrust, that this would result in loosing airspeed, entering a stall, and crashing

      So they realized that an alternative was to lower their angle-of-attack, preventing the stall, and maintaining a bit of airspeed. This would have the unfortunate side affect of landing well-short of the runway (and perhaps airport) and destroying the aircraft - but given the information available - was a bad - but the best alternative

      So they implicitly decided the best course of action was to glide the airplane and ditch it in a field - not a decision that would have exactly won them any praise had they read the situation wrong - but it saved everyone

    • by u38cg ( 607297 ) <calum@callingthetune.co.uk> on Sunday January 20, 2008 @12:47PM (#22117366) Homepage
      To my mind, if you manage to get 300 tonnes of falling metal out of the sky and on the deck with nothing worse than a broken leg, you've done something right.
    • Hmm, if I was the pilot, I would have pulled the wheels UP, to reduce drag, though it probably makes buggerall difference on a craft that big.
    • by IkeTo ( 27776 )

      It seems you didn't RTFM. Here's some help...

      The failure of the engines had cut the main power. The 777 does not have cables connecting wing flaps and rudder to the pilots' controls. It is all done by sending electronic signals. However, the plane has several back-up batteries that enable the instruments to work until the emergency power units kick in.

      "If they had done nothing, the autopilot would have tried to fly the glide path," said a former pilot. The plane would probably then have stalled and cra

    • by caseih ( 160668 )
      The wikipedia entry on the crash is pretty lucid and has all the latest actual facts as they are known. http://en.wikipedia.org/wiki/British_Airways_Flight_BA38 [wikipedia.org]

      As for the number of 777s in service, that's between 600-700, according to reports on Sky news. Another report said that Boeing reports they have around 300 pending orders for 777s over the next few years. A remarkably safe and capable plane. And this accident investigation will likely only make them safer.
  • Patience (Score:5, Insightful)

    by Linker3000 ( 626634 ) on Sunday January 20, 2008 @12:28PM (#22117238) Journal
    Let's just wait for the official forensics rather than patched together rumours shall we?
    • Re: (Score:3, Funny)

      Let's just wait for the official forensics rather than patched together rumours shall we?
      Um...what are you doing on /. then? Seriously though, this is the place to come for some relatively informed speculation (see for example comments by the jet maintenance guy earlier in the thread).
      • Re: (Score:2, Insightful)

        Seriously though, this is the place to come for some relatively informed speculation...

        Seriously though, this is the place to come for some two-bit speculation...

        Had to fix that for you. Go back and read any /. article about NASA problems and just see the posts from folks who "know better" than the rocket scientists.

        I think I had too much coffee this morning. I'm feeling a bit cranky.

      • Re: (Score:3, Insightful)

        by Linker3000 ( 626634 )
        Oh, I am well aware of the /. crowd's ability to generate 'fact' - it's even more impressive than Leeloo's reconstruction.

    • Re: (Score:2, Funny)

      by JavaTHut ( 9877 )

      Let's just wait for the official forensics rather than patched together rumours shall we?
      You must be new here ...
  • Typical (Score:5, Funny)

    by pyrrhonist ( 701154 ) on Sunday January 20, 2008 @12:33PM (#22117270)

    Once such a procedure was set, the plane would continue under automatic control until it reached an altitude of 250ft. Then a female computer voice would say, "Decide."

    It's uncanny how they made the flight control system sound just like my wife.

    As Coward stared at the controls, the autothrottle demanded more thrust.

    That's a feature that is sadly lacking, though.

  • by hey ( 83763 )
    Maybe programmers would get more respect if we wore snappy uniforms like pilots?
  • There is little to no point in uninformed speculation.

    The facts that we know so far are those in the interim AAIB report.

    The AAIB will publish their full report in due course, at which point we can expect to know what happened.

    That's it, basically.
  • It's still a bit early to jump to conclusions, but from now on I think I'll feel safer in planes that have not done away with the cables for transmission, and substituted them with an all-electronic control. If the software fails, I want the pilot to be able to _pull_ at the thing and have a nice physical path to the flaps, instead of an disconnected joystick.
  • by bradgoodman ( 964302 ) on Sunday January 20, 2008 @01:14PM (#22117556) Homepage
    It was a regular-'ol "single equals" bug:

    if (engines = OFF) {
    PrepareForCrash();
    }
  • by Anonymous Coward
    The problem was not computers. After extensive investigation, the authorities
    have released what actually caused the accident. The evidence is clearly visible
    in these pictures:

    http://www.heathrowpictures.com/pictures/images/picturegallery_baw_b772_gymmm20.jpg [heathrowpictures.com]

    The cause for the engine problems is massive ingestion of dirt. The manuals clearly
    specify that the engines need to be run on air, not dirt. Even small quantities
    of dirt can cause loss of power.
  • by caseih ( 160668 ) on Sunday January 20, 2008 @01:21PM (#22117608)
    A comment on airliners.net's forums is very appropriate for us slashdotters I think:

    A BA 772 landed short of the runway. Initially, speculation was entirely wild, ranging from random double engine failure to fuel contamination to one engine being actually working. Some witnesses said the plane came in high and fast, others said low and slow, others mixed the two together; all agree it was nose-high. A few helpful posters who actually knew something contributed. Some posters asked why the tires were brown...after the plane had skidded through a wet, grassy area on collapsed landing gear. A few posters got into pedantic discussions on various features of the 772 or its operational history as compared to the 340. Others took great pains to demonstrate to the world their lack of basic knowledge of unpowered flight. Few seemed familiar with the notion that fan blades windmill even when no power is applied to the engine. Most all were engaged in a game of nerdy one-upmanship in which they vigorously tried to validate their lofty views of themselves based on their aeronautical knowledge. In sum, we know about as much now as we did when the plane went down: the plane turned onto final, engines did not respond to power inputs, plane landed short of runway, slides deployed, people all survived, plane almost certainly a W/O. Shockingly, neither BA nor Boeing has decided to keep the 15-year-old speculation artists abreast of the situation.
  • by AlecC ( 512609 ) <aleccawley@gmail.com> on Sunday January 20, 2008 @01:42PM (#22117762)
    The first linked article is more-or-less gossip, and gives no reason to blame the avionics. Not to say that it wasn't, but we want some evidence. The second is a much more reasoned article, and gives a number of possibilities, including avionics but also a number of others, all of which is possible. My favourite is fuel contamination - but we shall see.

    The simple "running out of fuel" hypothesis is very unlikely. All aircraft are supposed to carry reserves to divert to another airport (not far in this case) plus ninety minutes flying. While cheapo airlines might short-cut on this, I cannot imagine BA doing so. There is no indication that the aircraft had been "stacked" for any length of time, so it shoudl have landed with two hours worth of fuel on board. There have been cases of aircraft being misfueled, but on a regular run between two sophisticated endpoints, this seems unlikely.
  • by flywithjoe.com ( 1223752 ) on Sunday January 20, 2008 @04:03PM (#22119092) Homepage
    Each engine has its own separate EEC. Each EEC has full authority over engine operation. In the normal mode, the EEC sets thrust by controlling EPR based on thrust lever position. EPR is commanded by positioning the thrust levers either automatically with the autothrottles, or manually by the flight crew.

    Engine flameout protection is provided for an auto-relight and rain/hail ingestion. The auto-relight function is activated whenever an engine is at or below idle with the FUEL CONTROL switch in RUN. When the EEC detects an engine flameout, the respective engine ignitors are activated.

    Fuel is supplied by fuel pumps located in the fuel tanks. The fuel flows through a spar fuel valve located in the main tank. It then passes through the first stage engine fuel pump where additional pressure is added. It flows through a fuel/oil heat exchanger where it is preheated. A fuel filter removes contaminants. If the filter becomes clogged, the filter will be bypassed, passing fuel directly to the engine. In that case, a Advisory EICAS message "ENG FUEL FILTER L/R" will be displayed.

    When main tank fuel pump pressure is low, each engine can draw fuel from its corresponding main tank through a suction feed line that bypasses the pumps.

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