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Malaysia Airlines Loses Contact With 777 en Route to Beijing

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  • #61
    Originally posted by B52STRATO View Post
    And "U-Tapao" would had intercepted an emergency call, but they don't mentioned if it was Pattaya APT or the Naval Air Base.

    Edit: U-Tapao NAB

    http://www.chinatimes.com/realtimene...8003502-260401

    Baddly online traduced : "In addition, the U.S. Embassy said the 2:43 U.S. military bases stationed in Thailand U-Tapao SOS signal was listening to some of Malaysia Airlines Flight MH370 emergency call, said the aircraft cabin facing disintegration driver call, they want a forced landing."
    How could they receive a SOS when the ATC received nothing?

    I don't get it
    Last edited by James Bond; 2014-03-08, 18:22. Reason: Spelling
    AirDisaster.com Forum Member 2004-2008

    Originally posted by orangehuggy
    the most dangerous part of a flight is not the take off or landing anymore, its when a flight crew member goes to the toilet

    Comment


    • #62
      Just thinking loud:

      AF447-like: Highly unlikely in a Boeing. The "autotrim" does not change the trim speed and AoA. The control law is basically "Displacement proportional to AoA", there is no big change in control laws, the pilots don't relay on the plane's systems to avoid a stall, because the plane is stallable even in normal law, the pilots are used to use the yoke to control AoA, and both control yokes move together, have a big amplitude movement, and are placed directly in front of the pilots and between their legs, so a "but I have been pulling up all the time" would not be a sudden realization by the other pilot. If all that was not enough, the weather was good with no big tall clouds, so pitot icing at 35000 ft is almost impossible, and there aren't many other ways that can fail all the pitots at once.

      Bomb: Due to the sudden event, plus the at least two persons flying with stolen passports, to his seems like a possible theory. However, if it was a terrorist attack, one would expect claims. After all, the intention of a terrorist attack is to generate terror, and that doesn't happen if people don't know that it was a terror attack.

      But there might be other reasons for a bomb, like to kill some specific person without anyone knowing that this was the intention. Also, murdercide by a pilot or someone else aboard cannot be ruled out, which can be done with a hand gun (happened before), although with the current secure cockpit rules it would be much harder shoot the pilot if that person is not a crewmember.

      Other technical issues: I would have expected a mayday call to be made unless it was technically impossible or the crew was too busy trying to regain control of the plane. After all, a precise location information and a quick launch of SAR are critical survival factors, especially when you are going down in the sea. And while the wise practice is "aviate, navigate, then communicate", cruising altitude normally leaves plenty of time to complete all of them. That means that most of the imaginable things like cabin fires, dual engine failures, etc. are unlikely. We need a catastrophic event to render communications technically impossible (example TWA) or to leave the pilots too busy fighting for control (like a wing structural failure).

      Unfortunately, a ditching seems very unlikely. I can't imagine a reasonable scenario where they have the ability to fly the plane and keep it under control but not to communicate.

      --- Judge what is said by the merits of what is said, not by the credentials of who said it. ---
      --- Defend what you say with arguments, not by imposing your credentials ---

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      • #63
        Originally posted by James Bond View Post
        How could they receive a SOS when the ATC received nothing?

        I don't get it
        Dunno, maybe some American units were left behind after the end of the annual exercice and with a part of their equipment (CG must have ended not so long ago)... or more realistic would be the invention of this story by this website.

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        • #64
          They have reportedly located a 12-mile oil slick in the Gulf of Thailand. That gulf is quite shallow so if the wreckage in there it should be located very soon, along with the flight recorders. I wonder if there is ACARS data that is not being released to the press after the AF447 data caused such enthisiastic speculation.

          Comment


          • #65
            The USN sent a Flight IIA Arleigh Burke DDG and a P-3C to the area.

            http://bigstory.ap.org/article/us-na...plane-search-0

            Comment


            • #66
              Originally posted by Gabriel View Post
              Just thinking loud:

              AF447-like: Highly unlikely in a Boeing. The "autotrim" does not change the trim speed and AoA. The control law is basically "Displacement proportional to AoA", there is no big change in control laws, the pilots don't relay on the plane's systems to avoid a stall, because the plane is stallable even in normal law, the pilots are used to use the yoke to control AoA, and both control yokes move together, have a big amplitude movement, and are placed directly in front of the pilots and between their legs, so a "but I have been pulling up all the time" would not be a sudden realization by the other pilot. If all that was not enough, the weather was good with no big tall clouds, so pitot icing at 35000 ft is almost impossible, and there aren't many other ways that can fail all the pitots at once.
              Well, as long as we are speculating... The 777 has a very different air data architecture with a single fault-tolerant ADIRU and a secondary unit (SAARU) for redundancy. The 2005 incident near Perth illustrated a vulnerability in that design due to a software anomaly and the fact that a 777 at that time could be dispatched with a faulty SAARU. The incident aircraft departed flight level uncommanded at over 10,000fpm and encounted simultaneous stall and overspeed warnings. In lesser hands, it might have been the first 777 fatal accident. It is significant to note that this type of air data failure had nothing to do with weather anomaly.

              The other issue was the autothrottle, which remains armed when the thrust lever disconnect switches are used (and also when the levers are manually moved) and will reengage when the airspeed (true or false) exceeds the FMC paramenters. The incident aircraft upset was complicated by the autothrottle commands overriding manual flight.

              Now, all of these things have since been addressed through AD's, software updates and procedural changes, so they shouldn't be a factor here. It just illustrates the stealth factors that also exist on Boeing FBW and the vulnerability FBW aircraft have to air data failures. I suppose there is also the possibility that certain directives or recommendations were not carried out fleetwide...

              Gabriel, I haven't read the report in years but I want to find time to do that this weekend. It is here: http://www.atsb.gov.au/media/24550/a...503722_001.pdf

              Comment


              • #67
                Originally posted by Evan View Post
                Well, as long as we are speculating... The 777 has a very different air data architecture with a single fault-tolerant ADIRU and a secondary unit (SAARU) for redundancy. The 2005 incident near Perth illustrated a vulnerability in that design due to a software anomaly and the fact that a 777 at that time could be dispatched with a faulty SAARU. The incident aircraft departed flight level uncommanded at over 10,000fpm and encounted simultaneous stall and overspeed warnings. In lesser hands, it might have been the first 777 fatal accident. It is significant to note that this type of air data failure had nothing to do with weather anomaly.

                The other issue was the autothrottle, which remains armed when the thrust lever disconnect switches are used (and also when the levers are manually moved) and will reengage when the airspeed (true or false) exceeds the FMC paramenters. The incident aircraft upset was complicated by the autothrottle commands overriding manual flight.
                Can you confirm all of the above?

                Honestly, I don't remember the dtails of that incident, but I think the problem was partly that the crew didn't grab manual control (or, as said in the "Child of the Magenta" video, didn't change from "what is it doing it now" to "why was it doing that then").

                In particular, I don't think that the AT can override manual inputs. Rather the contrary. Unlike the Airbus, the AT moves the throttle levers but the piolots can easily overpower that movement (as long as they have their hands in the levers, of course), and knowing the Boing philosophy in general, I strongly suspect that if the throttle lever position conflicts with what the AT wants to do, the FADEC will follow the thrust lever positions.

                However, and even when the issues of this incident have been addressed, I agree that some other software glitch cannot be discarded.

                Again, very likely some kind of unhappy pilot intervention (or lack of a happy pilot intervention) would likely be a factor if there was a software glitch, since the Boeing FBW philosophy is highly overridable by the pilots (without the need to force a control law downgrade by switching off systems) and, IIRC, there is some direct control backup in the yoke that doesn't relay in electronics at all.

                Gabriel, I haven't read the report in years but I want to find time to do that this weekend. It is here: http://www.atsb.gov.au/media/24550/a...503722_001.pdf
                Thanks. I'll try to look at it later in the weekend.

                --- Judge what is said by the merits of what is said, not by the credentials of who said it. ---
                --- Defend what you say with arguments, not by imposing your credentials ---

                Comment


                • #68
                  It appears the Russian passenger wasn't on the flight. He also had his passport stolen.

                  (Not confirmed by Russian Government yet.)
                  AirDisaster.com Forum Member 2004-2008

                  Originally posted by orangehuggy
                  the most dangerous part of a flight is not the take off or landing anymore, its when a flight crew member goes to the toilet

                  Comment


                  • #69
                    Originally posted by Gabriel View Post
                    In particular, I don't think that the AT can override manual inputs. Rather the contrary. Unlike the Airbus, the AT moves the throttle levers but the piolots can easily overpower that movement (as long as they have their hands in the levers, of course), and knowing the Boing philosophy in general, I strongly suspect that if the throttle lever position conflicts with what the AT wants to do, the FADEC will follow the thrust lever positions.
                    The AT has an arming switch on the MCP. At the time of the incident (2005) it functioned as follows: As long as the switch is in the armed position, the system can be disengaged using the pushbuttons but will remain active and will re-engage if the AP is not engaged and the (detected and considered valid) airspeed is less than an FMC calculated value for more than one second or if the thrust is below what is required for the flight mode at that time. If the thrust levers are physically moved by the pilot, the AT will return them to the FMC determined position. Yes, the pilot can continously override this by force but the proper thing to do is to disarm the AT using the MCP switch.

                    During the incident, the AT was left armed and was re-engaging and overridding pilot commands in manual flight. A hand on the levers would detect this, as I believe it did in this instance. Again, I'm going from memory a bit so read the report.

                    Comment


                    • #70
                      Originally posted by James Bond View Post
                      It appears the Russian passenger wasn't on the flight. He also had his passport stolen.

                      (Not confirmed by Russian Government yet.)
                      Yes, so far two pax with stolen passports.
                      A Former Airdisaster.Com Forum (senior member)....

                      Comment


                      • #71
                        Picture taken from a vietnamese patrol airplane, it shows a large oil slick (looks like debris to me)
                        A Former Airdisaster.Com Forum (senior member)....

                        Comment


                        • #72
                          Malaysian Maritime Enforcement Agency found a piece of "canvas" floating near Bachok

                          AirDisaster.com Forum Member 2004-2008

                          Originally posted by orangehuggy
                          the most dangerous part of a flight is not the take off or landing anymore, its when a flight crew member goes to the toilet

                          Comment


                          • #73
                            Originally posted by AVION1 View Post
                            Picture taken from a vietnamese patrol airplane, it shows a large oil slick (looks like debris to me)
                            It doesn't look like jet fuel (kerosene) at all to me which should be just an oily slick mostly colorless, maybe with some change in brightness and a rainbow effect, but not a brown stain.

                            This looks more like something like this:



                            Which is a sort of algae.

                            --- Judge what is said by the merits of what is said, not by the credentials of who said it. ---
                            --- Defend what you say with arguments, not by imposing your credentials ---

                            Comment


                            • #74
                              Originally posted by N-ONE View Post
                              Both Airbus and Boeing use onboard datalink systems that can tap into the the warning and maintenance functions (Airman for Airbus, AHM for Boeing).

                              In a similar manner to AF447 I would expect MH operations to have received similar data just prior to this loss.

                              And it is a great loss, my condolences to the families of this tragedy.

                              RIP
                              Can anyone follow up on this ? Is it possible an airline can pull up all data from a flight as it happens or has happened ?

                              Comment


                              • #75
                                Originally posted by B757300 View Post
                                Oh cool it.
                                Go away. This thread most likely will roll another 250 pages with nobody here being CERTAIN .


                                Moderated language by site moderator.
                                Last edited by brianw999; 2014-03-09, 15:41.

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