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Colgan 3407 - 10 years today

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  • Colgan 3407 - 10 years today

    Can you believe that...
    I guess time never stalls, no matter how relentlessly you pull up.

  • #2
    Originally posted by Evan View Post
    Can you believe that...
    I guess time never stalls, no matter how relentlessly you pull up.
    I respectfully suggest you stick with your day job.

    Was just talking about that crash with a colleague last week after he noted how young his pilots were on porter airlines...

    Comment


    • #3
      The PIC pulled up into a 30 degree attitude stall. The F/O reacted by retracting the flaps. The passengers were thrown into a 2G roller-coaster ride to their deaths. All in a span of about 20 seconds, before which they had been flying safely along in a major-airline-branded, perfectly-functional 21st century aircraft in calm weather conditions. This one still terrifies me to this day.

      Comment


      • #4
        Originally posted by Evan View Post
        The PIC pulled up into a 30 degree attitude stall after training on tail stalls. The F/O reacted by retracting the flaps. The passengers were thrown into a 2G roller-coaster ride to their deaths. All in a span of about 20 seconds, before which they had been flying safely along in a major-airline-branded, perfectly-functional 21st century aircraft in calm weather conditions hard IMC in icing. This one still terrifies me to this day.
        Fixed.

        Originally posted by 3BS
        Actually, "the pilots inadequately monitored airspeed even though leveling, flattening the props, dropping gear and adding flaps are well-known mechanisms to slow almost all aircraft [flapless, non-retractable, non-prop and non-adjustable prop planes excepted] and possibly trigger a stall warning [aircraft without stall-warnings excepted]. This one still terrifies me to this day.
        Now, it's fixed.
        Les règles de l'aviation de base découragent de longues périodes de dur tirer vers le haut.

        Comment


        • #5
          Originally posted by 3WE View Post
          after training on tail stalls... hard IMC in icing
          I don't buy this theory. Icing-related tailplane stalls do not trigger stickshaker, either in training or IRL. A trained response to stickshaker shouldn't be to assume tailplane icing.

          Nor should IMC factor into anything here.

          I concur that no one was looking at the speed tape, because the ice protection system moved the barberpole up and it would have been pretty obvious that speed was becoming (artificially) critical.

          But we've hashed this one to death. I'm just remarking how even the safest environments are only as safe as the pilots are well-trained, and even pilots flying for the majors can be this hazardously fatigued and unprepared. Hopefully the hard lessons of 2009 have not yet been forgotten.

          Comment


          • #6
            QUOTE=Evan +3BS

            I don't buy this theory. Fine- it is a far out theory that I have no special love for...but as to why someone would (again) do the FCOM/POH procedure on how TO stall...it remains a difficult question to answer...Gabieie might be right. Icing-related tailplane stalls do not trigger stickshaker, either in training or IRL. A trained response to stickshaker shouldn't be to assume tailplane icing.

            Nor should IMC factor into anything here. How goes the bicycle riding, Mr. Black and white? IMC is a higher work load with a lot more mental demands...and remember fatigue is cited as a contributing factor. And VMC NOT flying in icing and clouds might have a very different mental predisposition to the stick shaker. Please be more cautious with such absolute, black and white statements.

            I concur that no one was looking at the speed tape, because the ice protection system moved the barberpole up and it would have been pretty obvious that speed was becoming (artificially) critical. How about actually critical? I recall they rapidly burnt off 20 knots in relatively few seconds...the time until actual stall (and normal stall warnings) was not that far in the future...(although not all that far based upon my type specific training for a 172M where you check the speed every sec or slow...the same procedure that somehow would also have helped Asiana immensely- even though that was severe VMC conditions.)

            But we've hashed this one to death. I'm just remarking how even the safest environments are only as safe as the pilots are well-trained, and even pilots flying for the majors can be this hazardously fatigued and unprepared. Hopefully the hard lessons of 2009 have not yet been forgotten. Are you happy with changes in duty hour tracking and procedures? Are 'regional' partners now advertised with a more appropriate clarity?
            Les règles de l'aviation de base découragent de longues périodes de dur tirer vers le haut.

            Comment


            • #7
              Originally posted by 3WE View Post
              How about actually critical?
              Apparently they remained about 20kts above that. The reference speeds switch being activated, stickshaker speed was increased by 20kts. If you had checked the speed just before the barberpole showed up and were aware of the approximate rate of speed reduction and were busy with getting established on the ILS and configuration, you might assume your speed was ok for the moment. Especially if you were new to the type and didn't understand the function of the very type-specific speed reference switch. No excuse for not monitoring, but human factors...

              From the time the condition levers were moved to MAX they lost about 35kts in about 15 seconds. Stickshaker activated at 130kts in level flight as they transitioned from flaps 5 to flaps 10. Not a place you would expect a stall warning.

              Comment


              • #8
                Originally posted by Evan View Post
                Not a place you would expect a stall warning.
                Wrong.

                If I leveled and flattened props and and added flaps and never added power, I would expect a stall warning pretty soon: 35 kts in 15 seconds is a pretty impressive speed decay and only 20 kts to go...I think I would even expect a stall...leveling doesn’t give you much from the potential energy boosters...

                But alas, I know nothing of type specific Q-400 procedures...just 172s and shooting landings in 747-400s in MSFS... you really gotta keep on top of that 600,000 lbs of inertia...
                Les règles de l'aviation de base découragent de longues périodes de dur tirer vers le haut.

                Comment


                • #9
                  I still think (in contrast with the NTSB that says it is unlikely) that an attempt to recover a non-existent tail stall (and wrongly executed) is the best explanation. We will never know for sure one way or another, but here is way I think that way:

                  He underwent tail stall training more than once, including shortly before the accident in preparation for the winter season.
                  He had much more experience flying the SAAB that the Q-400 he had recently started flying. And probably he was more familiar with he SAAB's procedures and manuals than with the Q-400's.
                  The SAAB is susceptible to tail stall. The Q-400 is not. But he probably didn't know that.
                  The tail stall tends to happen at slowish approachish speeds, and the more extended the flaps the more likely.
                  The symptoms for a tail stall are: vibration in the control column, the yoke being shoved forward uncommanded, and the nose consequently going down.
                  The recovery is to pull up hard (winning over the uncommanded push-down force) as needed to bring the plane back to 1G level flight, add power to increase the airspeed, and retract flaps.
                  So they were flying in the approach, reducing the speed to what they thought was the correct approach speed (slower that the required Vref since they were not familiar with the effect of the ice switch on the stickshaker AoA and hence on Vref). 3WE says that they were slowing down too quickly and how on Earth they did not add thrust to correct that, but maybe slowing down was the intention and their speed goal was below the speed that triggered the sticshaker. Maybe he was somewhat aware of the speed, the had looked it up a couple of seconds ago and felt ok with slowing rte, maybe he overlooked the red dotted line in the speed tape... maybe... maybe... maybe.
                  They extend the flaps and shortly after they get the stickshaker.
                  Approach speed? ==> Yes
                  Just extended the flaps? ==> Yes
                  Control column shaking? ==> Yes (due to the stickshaker, not a tail stall, but he reacted in a fraction of a second, and if he was more or less aware of the speed, the pitch and the vertical speed, and understood a little bit about AoA and stall, and did not understand the effects of the ice switch, a stickshaker / stall made no sense whatsoever in that condition).
                  It's a tail stall!!!! (of course, the control column was not shoved forward uncommandedly and the nose shooting for the ground precisely, but oh well).
                  Recover procedure ==> Pull up (and now the yoke is being pushed forward against my will!!! See? A tail stall!!! - Of course it was the stick pusher, not the tail stall, but oh well)
                  Keep pushing up (and let's disregard the part of "as necessary to regain 1G level flight).
                  Advence throttles. What else we had in the recovery procedure? Oh yes!
                  Captain, do you want me to retract the flaps? -- Yes, please!!!
                  (and I can still feel the stick shaking and pushing down against my pull up attempts, so we still did not recover from the tail stall, let's keep fighting and pulling up)

                  It makes much more sense to me that: Split second sticksahker ==> Let's pull up hard just because.







                  But then we had AF, also in 2009.... And I don't think that that pilot thought it was a tail stall, and reacted almost identically.

                  --- 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


                  • #10
                    Originally posted by Gabriel View Post
                    I still think (in contrast with the NTSB that says it is unlikely) that an attempt to recover a non-existent tail stall (and wrongly executed) is the best explanation. We will never know for sure one way or another, but here is way I think that way:

                    He underwent tail stall training more than once, including shortly before the accident in preparation for the winter season.
                    He had much more experience flying the SAAB that the Q-400 he had recently started flying. And probably he was more familiar with he SAAB's procedures and manuals than with the Q-400's.
                    The SAAB is susceptible to tail stall. The Q-400 is not. But he probably didn't know that.
                    The tail stall tends to happen at slowish approachish speeds, and the more extended the flaps the more likely.
                    The symptoms for a tail stall are: vibration in the control column, the yoke being shoved forward uncommanded, and the nose consequently going down.
                    The recovery is to pull up hard (winning over the uncommanded push-down force) as needed to bring the plane back to 1G level flight, add power to increase the airspeed, and retract flaps.
                    So they were flying in the approach, reducing the speed to what they thought was the correct approach speed (slower that the required Vref since they were not familiar with the effect of the ice switch on the stickshaker AoA and hence on Vref). 3WE says that they were slowing down too quickly and how on Earth they did not add thrust to correct that, but maybe slowing down was the intention and their speed goal was below the speed that triggered the sticshaker. Maybe he was somewhat aware of the speed, the had looked it up a couple of seconds ago and felt ok with slowing rte, maybe he overlooked the red dotted line in the speed tape... maybe... maybe... maybe.
                    They extend the flaps and shortly after they get the stickshaker.
                    Approach speed? ==> Yes
                    Just extended the flaps? ==> Yes
                    Control column shaking? ==> Yes (due to the stickshaker, not a tail stall, but he reacted in a fraction of a second, and if he was more or less aware of the speed, the pitch and the vertical speed, and understood a little bit about AoA and stall, and did not understand the effects of the ice switch, a stickshaker / stall made no sense whatsoever in that condition).
                    It's a tail stall!!!! (of course, the control column was not shoved forward uncommandedly and the nose shooting for the ground precisely, but oh well).
                    Recover procedure ==> Pull up (and now the yoke is being pushed forward against my will!!! See? A tail stall!!! - Of course it was the stick pusher, not the tail stall, but oh well)
                    Keep pushing up (and let's disregard the part of "as necessary to regain 1G level flight).
                    Advence throttles. What else we had in the recovery procedure? Oh yes!
                    Captain, do you want me to retract the flaps? -- Yes, please!!!
                    (and I can still feel the stick shaking and pushing down against my pull up attempts, so we still did not recover from the tail stall, let's keep fighting and pulling up)

                    It makes much more sense to me that: Split second sticksahker ==> Let's pull up hard just because.







                    But then we had AF, also in 2009.... And I don't think that that pilot thought it was a tail stall, and reacted almost identically.
                    I guess it's a reasonable theory if stickshaker can be confused with aerodynamic vibration. And if the PF is not looking at the attitude indicator. As I recall, the F/O retracted flaps without instruction or approval from Renslow.

                    Comment


                    • #11
                      Originally posted by Evan View Post
                      As I recall, the F/O retracted flaps without instruction or approval from Renslow.
                      1. Yes, what's your point?

                      2. Retracting the flaps was a bad thing to do at that particular time, but it is part of many control-problem procedures which are frequently rehearsed to the point of being a memory item. Disobeying Renslow by shoving forward and over powering him (without instruction or approval) would have been a good thing to do.

                      3. Google United 585 and read what the FO did as the plane "spun" towards the ground. My recollection of the CVR transcripts are that it is frighteningly similar without a lot CRM discussion of whether it was captain-approved or not. (who wants to formally discuss things while falling the very few thousands of feet and seconds to an almost guaranteed death that existed for both of these)

                      4. I seem to recall something in my 172 POH about reducing flaps when recovering from a few different things.

                      While I THINK I would not do that (although I lack Q-400 type specific training), it is not_among the mind-boggling deliberate-and-incorrect actions that were done that night.
                      Les règles de l'aviation de base découragent de longues périodes de dur tirer vers le haut.

                      Comment


                      • #12
                        Points (#2 and #4 mostly) taken, but... part of being a competent pilot is having a good general idea of what to do with the flight controls when. Low airspeed: flaps good. High airspeed: flaps bad. It's not that complicated.
                        Be alert! America needs more lerts.

                        Eric Law

                        Comment


                        • #13
                          Originally posted by 3WE View Post
                          1. Yes, what's your point?
                          My point is that the following is inaccurate:

                          Captain, do you want me to retract the flaps? -- Yes, please!!!
                          The actual response was:

                          22:16:42.2 HOT-1 [sound of grunt] *ther bear.

                          it is not_among the mind-boggling deliberate-and-incorrect actions that were done that night.
                          I'm putting it down as deliberate-and-incorrect.

                          Comment


                          • #14
                            Originally posted by elaw View Post
                            Points (#2 and #4 mostly) taken, but... part of being a competent pilot is having a good general idea of what to do with the flight controls when. Low airspeed: flaps good. High airspeed: flaps bad. It's not that complicated.
                            Concur.

                            Originally posted by Evan
                            I'm putting it down as deliberate-and-incorrect.
                            Indeed, it was deliberate and incorrect and I want to think I would not do that. But don't forget your favorite phrase "startle factor" and your love of frequent recurrent, type-specific instant-memory-procedure regurgitation training...I can see her behavior as a result of repeated loss-of-control training.

                            AND

                            Your comment is consistent with what I said and Eric's partial agreement: not_among the mind boggling actions although it is among the deliberate and incorrect actions.
                            Les règles de l'aviation de base découragent de longues périodes de dur tirer vers le haut.

                            Comment


                            • #15
                              Okay- I see that on United 585 that a flap reduction was called for by the PF and selected by the PNF (in contrast with it not_being called for by the PF in Colgan and it's a call for go-around flaps vs. no flaps...similar, but different).

                              It is still a creepy similar course of events (not that mistakes are comparable) Gabieee also likes to point out that less nose-up input by the hard-over pilots would have given them an upright and theoretically airborne aircraft.


                              09.43:03 CAM-1 Thirty flaps.
                              09.43:08 CAM-2 Wow.
                              09.43:09 CAM [Sound similar to that of an enginepower reduction]
                              09.43:28.2 CAM-2 We're at a thousand feet.
                              09.43:32.6 CAM-2 Oh, God (flip)-
                              09.43:33.5 CAM-1 Fifteen flaps.
                              09.43:34 CAM-2 Fifteen.
                              09.43:34.4 CAM-2 Oh
                              09.43:34.7 CAM-1 Oh! [exclaimed loudly]
                              09.43:35.5 CAM [Click sound similar to that ofa flap lever actuation]
                              09.43:34.7 CAM-1 #.
                              09.43:36.1 CAM [Click sound similiar to that ofa flap lever actuation]
                              09.43:36.5 CAM-1 No! [very loud]
                              09.43:37:4 CAM [Click sound similiar to that ofa flap lever actuation]
                              09.43:38.4 CAM-2 Oh my God... [unidentifiable clicksound] Oh my God! [a scream]
                              09.43:40.5 CAM-1 Oh no (#) [exclaimed loudly]
                              09.43:41.5 CAM [Sound of impact]
                              Les règles de l'aviation de base découragent de longues périodes de dur tirer vers le haut.

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