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  • Originally posted by Evan View Post
    It seems to me that until a large capacity passenger aircraft is involved with hundreds of lives lost, nothing seems to motivate the industry to deal with this kind of issue.
    Well, not "the industry" at great, but some are doing something.
    Originally posted by ATSB EK accident report
    Take-off securing function
    In July 2009, Airbus announced in their Safety First magazine that they were
    developing a software package called the ‘Take-off Securing’ (TOS) function. The
    TOS function automatically checks the data being entered into the flight
    management and guidance system (FMGS) for consistency between the take-off
    parameters. A check is carried out on the takeoff reference speeds entered into the
    FMGS against take-off limitation speeds calculated within the FMGS based on the
    aircraft weight. If the TOS function detects a discrepancy between these speeds, it
    alerts the flight crew by displaying a message on the FMGS display unit.
    On 28 May 2010, Airbus provided the ATSB with the results of a simulation of the
    TOS function for the A340 using the accident flight take-off performance
    parameters.
    On 28 October 2011, Airbus advised that they plan an additional development that
    will include functionality to check that the aircraft has sufficient runway length to
    support a safe takeoff.

    --- 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


    • Originally posted by BoeingBobby View Post
      Not going to go down this path again!! And learn to use spell check would you!
      I don't see the point in using a computer to check something like spelling. The old fashioned way works fine. Of course, humans do make mistakes from time to time, including when they are punching data into a computer.
      Les règles de l'aviation de base découragent de longues périodes de dur tirer vers le haut.

      Comment


      • Originally posted by 3WE View Post
        I don't see the point in using a computer to check something like spelling. The old fashioned way works fine. Of course, humans do make mistakes from time to time, including when they are punching data into a computer.
        Well maybe we should install some kind of device that warns you while you are typing before you make the spelling error! It could have all kinds of flashing lights and horns and wailers and lots of other good stuff! And also maybe a marker on the side of the keyboard that you can look at while you are typing to make sure you haven't gone to far down the line or page!!!

        Comment


        • Originally posted by BoeingBobby View Post
          And the National 74 in Bagram was a load shift on T.O. How would you figure that this had to do with T.O. performance?
          Gabriel is referring to this. It was a 747, everyone died and it had everything to do with take-off performance:

          Boeing 747: October 2004

          Location: Halifax, Canada
          On 14 October 2004, a Boeing 747-244SF, registered 9G-MKJ, attempted to take off from runway 24 at the Halifax International Airport. The aircraft overshot the end of the runway for a distance of 825 ft (251 m), became airborne for 325 ft, then struck an earth mound. The aircraft’s tail section broke away from the fuselage, and the aircraft remained in the air for another 1,200 ft before it struck terrain and burst into flames. The aircraft was destroyed by impact forces and a severe post-crash fire. All seven crew members were fatally injured. The Transportation Safety Board of Canada (TSB) found that the accident resulted from a flight crew member not recognising that the laptop computer used to calculate the take-off performance data contained an incorrect aircraft weight from the previous flight. This incorrect weight was used to calculate performance data for the takeoff from Halifax, which resulted in incorrect take-off speeds and thrust settings being generated by the laptop computer. The crew then used the incorrect speeds and thrust settings which were too low to enable the aircraft to take off safely for the actual weight of the aircraft. The Canadian TSB issued the following recommendation in the investigation report released on 29 June 2006:

          Therefore, the Board recommends that:
          The Department of Transport, in conjunction with the International Civil Aviation Organization, the Federal Aviation Administration, the European Aviation Safety Agency, and other regulatory organizations, establish a requirement for transport category aircraft to be equipped with a take-off performance monitoring system that would provide flight crews with an accurate and timely indication of inadequate take-off performance
          [Recommendation A06-07].
          BTW, have they released an official finding on the Bagram 747 crash?

          Comment


          • Originally posted by BoeingBobby View Post
            1- Air Florida was pilot error! Failure to use proper anti-ice procedures.
            2- And the National 74 in Bagram was a load shift on T.O. How would you figure that this had to do with T.O. performance?
            3- Curious, Are you still in touch with ITS? I would love to have his input on this.
            1- Almost all of them are pilot error. Or who would you blame for entering the wrong take-off data? The lack of a take-off performance monitoring system can never be the cause of the accident, but it might prevent it, and it would have very likely done so in Air Florida where the actual thrust was much lower than the one indicated in the engine instruments due to iced-up probes.

            2- As Evan said.

            3- No, not in contact unfortunately. I'd also love to have his input. I foresee that it'd be quite similar to yours.

            --- 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


            • Originally posted by Evan View Post
              Gabriel is referring to this. It was a 747, everyone died and it had everything to do with take-off performance:

              BTW, have they released an official finding on the Bagram 747 crash?
              I had forgotten about the MK crash. However this again was do to pilot error. The takeoff data was used from the previous flight, and the weights were much different.

              Load shift with a possibility that the cargo floor gave way. This was a BCF (Boeing converted freighter) aircraft, which is a passenger aircraft that was converted to a freighter. The cargo floors are not the same as a regular freighter.

              Comment


              • Originally posted by BoeingBobby View Post
                I had forgotten about the MK crash. However this again was do to pilot error. The takeoff data was used from the previous flight, and the weights were much different.
                Air Florida was pilot error! Failure to use proper anti-ice procedures.
                Yes, and EK was pilot error too. And so?
                I don't get the point.

                --- 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


                • Takeoff with non-takeoff flap is a pilot error - Takeoff config warning.
                  Takeoff with spoilers extended is a pilot error - Takeoff config warning.
                  Landing with the gear up/flaps not in landing position is a pilot error - Landing config warning.
                  Flying above/below appropriate speeds are pilot errors - overspeed/stall warning.
                  Taking off with incorrect thrust settings can be a pilot error - .....

                  Comment


                  • Originally posted by MCM View Post
                    Takeoff with non-takeoff flap is a pilot error - Takeoff config warning.
                    Takeoff with spoilers extended is a pilot error - Takeoff config warning.
                    Landing with the gear up/flaps not in landing position is a pilot error - Landing config warning.
                    Flying above/below appropriate speeds are pilot errors - overspeed/stall warning.
                    Taking off with incorrect thrust settings can be a pilot error - .....
                    Originally posted by Gabriel View Post
                    Yes, and EK was pilot error too. And so?
                    I don't get the point.

                    And where will all the lights, bells and whistles end?

                    For those that are small airplane drivers, and the flight sim jockeys..

                    80% of all WIDE BODY aircraft accidents, (YES 80%) are a direct result of an RTO (Rejected takeoff). So let us say that you somehow figure out a way to add yet another warning system into the fleet to warn of an apparent non-appropriate acceleration rate. What now happens when the system either, a) fails, or b) gives a false warning? Is the system going to be able to be deferred if it is inoperative? Or is the aircraft now grounded? Is is going to be a stand alone system or will there be redundancy?

                    Just for the hell of it, I am operating one of our -8's from Hong Kong to Dhaka and then to Abu Dhabi tomorrow morning. They are both just about the same stage length (4:30) so they should be just about the same weight. I am going to make an effort to take a look outside at V1 and see about how much runway is left.

                    Comment


                    • And where will all the lights, bells and whistles end?
                      They'll end when we stop taking off with incorrect configurations and insufficient thrust!

                      What now happens when the system either, a) fails, or b) gives a false warning? Is the system going to be able to be deferred if it is inoperative? Or is the aircraft now grounded? Is is going to be a stand alone system or will there be redundancy?
                      Come on BB, you can see perfectly well how this would work. Its exactly the same concept as that nice takeoff config warning that you hopefully don't get to fire off on your flights. Inhibited above 80kts.

                      This isn't hard BB. We kept taking off with incorrect flap settings, and we've now got an automated alert. We kept having near misses with landing gear and landing flap settings - so we have alerts. We try to use incorrect runways - so a voice alert for that has been developed too. And now we keep on taking off with incorrect thrust - its not unreasonable to expect a non-intrusive backup configuration alert to have thrust inputs into it too.

                      Seems extremely sensible to me.

                      Comment


                      • Originally posted by MCM View Post
                        They'll end when we stop taking off with incorrect configurations and insufficient thrust!



                        Come on BB, you can see perfectly well how this would work. Its exactly the same concept as that nice takeoff config warning that you hopefully don't get to fire off on your flights. Inhibited above 80kts.

                        This isn't hard BB. We kept taking off with incorrect flap settings, and we've now got an automated alert. We kept having near misses with landing gear and landing flap settings - so we have alerts. We try to use incorrect runways - so a voice alert for that has been developed too. And now we keep on taking off with incorrect thrust - its not unreasonable to expect a non-intrusive backup configuration alert to have thrust inputs into it too.
                        It has? Must be an IPad app. We don't have any system in any of our 50 airplanes for that!

                        And WE have never done any of those things!

                        You did not answer any of my questions.

                        Hypothetical situation, You are rolling down the runway at max takeoff weight of 987 thousand pounds, 7 knots below calculated V1 (This will be around 160 knots) the slow acceleration warning system erroneously goes off. The Captain aborts, the aircraft blows 3 or 4 tires on the right side of the aircraft, goes off the side of the runway into a) the dirt, b) the water, c) 3 foot snow drifts, d) even worse the parallel runway on that side with another airplane on it.

                        And your thoughts are?

                        Comment


                        • Originally posted by BoeingBobby View Post
                          It has?
                          Hypothetical situation, You are rolling down the runway at max takeoff weight of 987 thousand pounds, 7 knots below calculated V1 (This will be around 160 knots) the slow acceleration warning system erroneously goes off. The Captain aborts, the aircraft blows 3 or 4 tires on the right side of the aircraft, goes off the side of the runway into a) the dirt, b) the water, c) 3 foot snow drifts, d) even worse the parallel runway on that side with another airplane on it.

                          I still don't think you're quite following what MCM is proposing BB. Nothing is going to happen at 160kts because, like the configuration alarm, the caution is inhibited at 80kts. The scenario you describe could just as well occur with a configuration warning if not for that speed-inhibition. The question of course is whether 80kts is sufficient or at what speed the alarm could be inhibited and still provide protection against overrun or tail strikes. But certainly a good measure before V1.

                          A valid counter-argument would be to consider the effect this might have on pilot complacency, envisioning a scenario somewhat like the way the configuration alarm system failed to save Spanair 5022. But that is always the argument against protection systems and in the end they save more lives than they ever endanger.

                          If you still find it so objectionable though, we could agree to require it only on passenger aircraft to begin with...

                          Comment


                          • Originally posted by BoeingBobby View Post
                            And where will all the lights, bells and whistles end?

                            For those that are small airplane drivers, and the flight sim jockeys..

                            80% of all WIDE BODY aircraft accidents, (YES 80%) are a direct result of an RTO (Rejected takeoff). So let us say that you somehow figure out a way to add yet another warning system into the fleet to warn of an apparent non-appropriate acceleration rate. What now happens when the system either, a) fails, or b) gives a false warning?"
                            The same could be said of the take-off configuration warning, and the system would alert you early in the take-off roll if the acceleration is below the expected threshold. I don't know how it will be desgigned, but it could be inhibited above 80 knots, for example. In all the accidents that were the result of poor take-off performance the gap would have been detected much earlier than that.

                            Nobody is talking (at least not at this stage of the thread) about checking for the performance at V1.

                            Is the system going to be able to be deferred if it is inoperative? Or is the aircraft now grounded? Is is going to be a stand alone system or will there be redundancy?
                            The same could be said of the take-off configuration warning, except that the system would be highly reliable because it would depend just on the acceleration info already available in the plane, the runway info, and a software code. In fact, it seems that absolutely nothing new has to be installed in the plane (except the software), so it's not like they are adding new failure modes.

                            Just for the hell of it, I am operating one of our -8's from Hong Kong to Dhaka and then to Abu Dhabi tomorrow morning. They are both just about the same stage length (4:30) so they should be just about the same weight. I am going to make an effort to take a look outside at V1 and see about how much runway is left.
                            And do you know how much additional runway you would have needed to complete the T/O and reach V2 and 35 ft with an engine failed at V1? Or how much to stop the airplane after aborting at V1?

                            As a reference, EK had 1100m (3600ft) remaining when they called "V1". That looks like a good bunch and is part of the reason why they didn't note by then that something was wrong. And still, they couldn't separate the plane from the ground until hundreds of meters past the end of the runway, and we are talking of all engines operating and the captain setting max thrust at the first tail strike.

                            --- 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


                            • Originally posted by MCM View Post
                              This isn't hard BB. We kept taking off with incorrect flap settings, and we've now got an automated alert. We kept having near misses with landing gear and landing flap settings - so we have alerts. We try to use incorrect runways - so a voice alert for that has been developed too. And now we keep on taking off with incorrect thrust - its not unreasonable to expect a non-intrusive backup configuration alert to have thrust inputs into it too.

                              Seems extremely sensible to me.
                              GPWS (then it was not enough so now EGPWS), TCAS, bank angle alert, altitude alert (750 ft before you reach the selected altitude or when you depart the selected altitude), envelope protection, spoilers that auto-stow when you add thrust (to prevent that you forgot to do it during a ground avoidance maneuver), minimum selectable speed... The list could go almost forever.

                              Let's face it. Not that I like it, but most of the safety improvement in aviation came from protecting the pilots (or other humans) from themselves.

                              --- 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


                              • It has? Must be an IPad app. We don't have any system in any of our 50 airplanes for that!
                                It is not an iPad app, it is an integrated system using the EGPWS. It is a system developed by Honeywell, in the form of RAAS, or SmartLanding/SmartRunway. Just because your airline hasn't chosen to implement the available systems doesn't mean they don't exist. Airlines who have it installed in some, if not all of their aircraft include Lufthansa, BA, Emirates, Qantas, Alaskan, and I'm also told FEDEX. There are more.

                                Clearly the progression of aircraft systems holds no interest for you.

                                [QUOT] And WE have never done any of those things![/QUOTE]

                                Yes, as an industry, we have.

                                You did not answer any of my questions.
                                Actually, yes I did. You just didn't want to think.

                                To say it again: Its exactly the same concept as that nice takeoff config warning that you hopefully don't get to fire off on your flights. Inhibited above 80kts. That includes the same MEL requirements and requirements to be inhibited above 80kts for us Boeing people. But I'll answer your hypothetical.

                                Hypothetical situation, You are rolling down the runway at max takeoff weight of 987 thousand pounds, 7 knots below calculated V1 (This will be around 160 knots) the slow acceleration warning system erroneously goes off. The Captain aborts, the aircraft blows 3 or 4 tires on the right side of the aircraft, goes off the side of the runway into a) the dirt, b) the water, c) 3 foot snow drifts, d) even worse the parallel runway on that side with another airplane on it.

                                And your thoughts are?
                                My thoughts are that a pilot taking off with insufficient thrust is a far more likely event to occur than an erroneous warning close to V1 that the Captain incorrectly decides to abort for. That take off is also more likely to cause damage/injury than the high speed abort if it was accidentally conducted.

                                The warning is inhibited above 80kts, just like all of the other configuration warnings. I can't see why it would be any more likely to give a false warning above its inhibited speed than the other configuration warnings, and none of those seem to be regularly going off incorrectly.

                                Below 80kts, then it doesn't matter any more than a flap config alert.

                                The Captain should not be rejecting at 7 kts below V1 for a configuration warning. You know this. An erroneous takeoff flap configuration warning at that speed is also possible. We don't abort for that. Does that mean we shouldn't have it? I'm starting to think you do think this.

                                However, even if the Captain does reject, then he will still be able to stop the aircraft within the distance available as he is below V1. Just because he blows tyres on the aircraft should not make the aircraft leave the sealed surface. We've had 747's perform high speed RTO's and lose all the tyres on one side, and still be sitting quite happily on the centreline. I'm not sure why you think they'll end up on the adjacent runway. Just becomes a bit inconvenient to move them afterwards.

                                I agree that a high speed RTO is a significant event, but this system would not be any more likely to induce one than a flap config alert. Similarly, take offs with insufficient thrust are a significant event, and in the last few years we've had a number of them resulting in significant damage. On the balance, I strongly believe we will have a better safety outcome by installing such a system than not. And I don't think we're too far away from seeing them, whether we like it or not.

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