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TransAsia airplane crashes in Taipei (ATR 72)

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  • #16
    Reuters confirms Mayday call



    Reuters seems fairly certain that they maydayed and declared engine flame out.

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    • #17
      The aircraft seems to come down wings virtually level until the last seconds when the left wing suddenly drops. I get the feeling that the pilots tried to avoid the buildings and go for the river but stalled after doing so.
      If it 'ain't broken........ Don't try to mend it !

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      • #18
        The car cams are on westbound Huandong Highway travelling towards the airport. The river at this point is a little south of the runway line. The plane is coming from further south banking to port (north). That means it had turned at least 20/30 degrees to starboard after take off to get into that position. That would have been roughly in line with the river further down before it executes this bend to the north. It could be that he was intending to go down there but had too much speed/altitude and decided to hop those building on the left and ran out of both.

        The impact point is here: 25.062723,121.617426

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        • #19
          The adage was "never turn into a (the direction of), a dead engine", since that is what will lead to a stall and at take off and landing speeds there is no margin for that error. It seems that the desire to get back to the field takes over when it should be to fly the airplane and identify the dead engine before making any directional changes. This is the same scenario that Richard Collins of Flying Magazine took a lot of heat for when he announced that he won't get on a twin since few crews spend enough time in practicing the proper recovery for a dead engine.
          Live, from a grassy knoll somewhere near you.

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          • #20
            The old saying of "Turn towards the dead engine and the good one will take you to your crash site" was well demonstrated here unfortunately.
            If it 'ain't broken........ Don't try to mend it !

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            • #21
              Originally posted by guamainiac View Post
              The adage was "never turn into a (the direction of), a dead engine"...This is the same scenario that Richard Collins of Flying Magazine took a lot of heat for when he announced that he won't get on a twin since few crews spend enough time in practicing the proper recovery for a dead engine.
              1) Can't yet say for certainty- but I'm wondering if there were some terrain issues that limited what they could and couldn't do turn-wise?

              2) The Collin's deal needs to be considered from a number of angles...

              A) A long, long list of engine-out-loss-of-control crashes supports it, along with stats that a lot of twins have higher engine failure fatality rates than a lot of singles. I always "arm chaired" that a typical single engine twin airplane is flyable, but the few times I tried it on the poorly-representative MSFS, it was a bit scary how often the airspeed decayed while I tried to hold altitude, and next thing I knew I was falling out of the sky with one wing stalled due with crossed up controls and asymmetrical thrust.

              Conversely


              B) The "few crews who practice enough" would tend to include airliner types whom I assume do some fairly regular engine failure scenarios in their recurrent simulator sessions- plus I always seem to read about fancy automation on modern, big planes that assists with engine failures...
              Les règles de l'aviation de base découragent de longues périodes de dur tirer vers le haut.

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              • #22
                How soon before they try to blame it on a pilot who ignored stall warnings and pulled back on the yoke instead?

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                • #23
                  Originally posted by 3WE View Post
                  The weather there seems plenty warm- i.e. no large super cooled droplet icing that makes the stall speed and behavior pretty nasty on this plane.

                  ...and tough to say from the video, but there doesn't seem to be too much yawing or hard control inputs...i.e. parlour speculation that both engines were producing power or both were not producing power.
                  The stall didn't need to happen at the start of the sequence. Rather, it looks to me that they had another problem and the stall came late, perhaps as the result of an (always impossible) attempt to sustain flight or stretch a glide beyond the plane's capabilities that were impaired by said initial problem.

                  But that the plane is stalling just before the roll upset, I have little doubt.

                  --- 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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                  • #24
                    Originally posted by Gabriel View Post
                    The stall didn't need to happen at the start of the sequence...
                    Concur.

                    Not trying to suggest otherwise...

                    ...just that if it's stalled now, previous stalls warrant discussion...

                    ...even if if the discussion is to promptly place it the "probably not" list (along with deliberately pulling up relentlessly in contrast to what taught in hour 1 of flight school).
                    Les règles de l'aviation de base découragent de longues périodes de dur tirer vers le haut.

                    Comment


                    • #25
                      Originally posted by brianw999 View Post
                      The old saying of "Turn towards the dead engine and the good one will take you to your crash site" was well demonstrated here unfortunately.
                      Originally posted by Me when I first posted here
                      I tend to disagree...this plane made it a good distance perhaps a whole mile and arrived just short of the crash site wings level.

                      The "turn towards the dead engine" scenario usually happens more immediately after takeoff when you have "no altitude" and are trying to get it and you don't manage your airspeed quite well enough (nor maintain the mental toughness to keep the painfully slow climb at the speed needed for rudder authority.

                      These guys went a mile with no apparent climb, AND looking under control from the roll standpoint, and essentially no visually apparent yaw that you'd probably see if one engine was pulling you out of control.
                      Edit: It appears that the red stuff is wrong- and that the final roll may likely HAVE been one engine pulling them out of control...But (as Gabriel alluded to below), I maintain my disagreement: I do not think this is a "classic, ill-advised, pilot-initiated turn towards the dead engine", as much as a stall with asymmetrical power. Additionally, the stall may not have been an oblivious, relentless pull up, as much as a valid fight for the last bit energy to miss the buildings.

                      My thought that one should be able to see the yaw was apparently parlour-talk-ass-hattery.

                      Or, then again, I could be totally wrong.

                      And, I guess I'll go back and edit this a second time...perhaps this was a situation of having no power at all and the wing drop was stall-related, without asymmetrical power.
                      Les règles de l'aviation de base découragent de longues périodes de dur tirer vers le haut.

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                      • #26
                        Originally posted by 3WE View Post
                        I tend to disagree...this plane made it a good distance perhaps a whole mile and arrived just short of the crash site wings level.

                        The "turn towards the dead engine" scenario usually happens more immediately after takeoff when you have "no altitude" and are trying to get it and you don't manage your airspeed quite well enough (nor maintain the mental toughness to keep the painfully slow climb at the speed needed for rudder authority.

                        These guys went a mile with no apparent climb, AND looking under control from the roll standpoint, and essentially no visually apparent yaw that you'd probably see if one engine was pulling you out of control.
                        They climbed about 1000ft before starting to descend.
                        Regarding the yaw, very hard to tell. I agree that there is no significant yaw MOTION, but if the plane was already in a sideslip is almost impossible to tell from the cameras mounted in moving vehicles.

                        And, at least in the video sequence, there is no significant left TURN. rather a uncontrolled left roll. They didn't turn into the dead engine. Perhaps they could not avoid the plane form doing it by itself, though.

                        --- 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


                        • #27
                          Originally posted by 3WE View Post
                          plus I always seem to read about fancy automation on modern, big planes that assists with engine failures...
                          The ATR-72 has something called Automatic Takeoff Power Control System (ATPCS) that works on takeoff when power is at the TO setting. The remaining engine is 'uptrimmed' to 100% and the failed prop is feathered.

                          Unless it also fails...

                          This quote from http://atr.flight1.net

                          Originally posted by Asfrag
                          That's why in case of engine failure after take off you MUST check that the Up trim AND the Auto feather system work properly.. otherwise you have to move the PL manualy to 100% and the failed prop CL's to FEATHER or the aircraft will be very hard to control, believe me
                          The FDR will show us the PL and CL positions.

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                          • #28
                            Originally posted by guamainiac View Post
                            This is the same scenario that Richard Collins of Flying Magazine took a lot of heat for when he announced that he won't get on a twin since few crews spend enough time in practicing the proper recovery for a dead engine.
                            He was getting a lot of invitations, was he?

                            Comment


                            • #29
                              If you look at one of those videos you notice a distinct burst of dark smoke belching out of one of the engines just before the descent/stall happens. I wonder if either they lost the second engine at that point or if the single engine flameout and "Mayday, engine flameout" call actually happens then, just before impact. Whatever causes it, it's definitely on that video.

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                              • #30
                                Originally posted by Evan View Post
                                ...I wonder if either they lost the second engine...
                                Are we ready to say the F-dash-dash-dash word.

                                Contamination? 100LL?
                                Les règles de l'aviation de base découragent de longues périodes de dur tirer vers le haut.

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