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Accident avoided despite the efforts of the crew

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  • #16
    Originally posted by guamainiac View Post
    3WE, you have to stab at the rudder pretty hard for a steep slip.
    See Brians Youtube of a B-52...

    I think a pretty good slip occurs.
    Les règles de l'aviation de base découragent de longues périodes de dur tirer vers le haut.

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    • #17
      Fully aware, but that is NOT a slip. It sure did slip sideways in the vertical but a slip to get rid of altitude involves cross controls.

      Gabriel?
      Live, from a grassy knoll somewhere near you.

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      • #18
        ^^^
        Perfectly correct. The B52 incident is a perfect example of insufficient airspeed, excessive angle of bank and total loss of lift.....

        .....AKA.....

        A stall !

        Fatal in this case.
        If it 'ain't broken........ Don't try to mend it !

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        • #19
          Originally posted by guamainiac View Post
          Fully aware, but that is NOT a slip. It shore did slip sideways in the vertical but a slip to get rid of altitude involves cross controls.

          Gabriel?
          The problem with the B52 was a stall or near stall that rendered the ailerons ineffective. Very similar to this C-17 accident, where the pilot applied full anti-bank aileron but the airplane didn't respond.

          The military has released video showing the moments just before a a C-17 crashed. Four people were killed in the July incident in Alaska. A pilot's overly ag...


          I've said it n times, but here it goes again. In a stall (or even near one) there is a serious degradation of the roll damping and of the aileron effectiveness. Not a good combination. FIRST lower the AoA, THEN recover from the bank.

          Any sideslip that there might have been present was not a factor.

          --- 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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          • #20
            Originally posted by guamainiac View Post
            Fully aware, but that is NOT a slip. It sure did slip sideways in the vertical but a slip to get rid of altitude involves cross controls.

            Gabriel?
            [Serious discussion mode, no flaming intended]

            Um...wrong...a slip is when the plane is not in a coordinated turn BUT INSTEAD is "sliding in and down"- the bank is too much for the turn rate.

            ...and then there's the 'opposite' which is a skid- the bank is too little for the turn rate.

            This can be acheived in any number of ways- and the controls do not have to be crossed...just not properly balanced (or perhaps turbulence is helping a bit).

            Now, a deliberate slip to burn altitude* (something not real relevant to the airline world) is generally done with crossed controls.

            *(or to deal with a crosswind, or to practice dutch roll coordination exercises, or to dip a wing for a good view, without changing heading)

            Gabriel?

            [/serious]
            Les règles de l'aviation de base découragent de longues périodes de dur tirer vers le haut.

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            • #21
              Good clarity, not a flame at all, thanks ... unless our resident "Perfesser at Large" (Gabe), weighs in with half a chalkboard of equations?

              I can't even begin to imagine how someone with that much time would even attempt a slip being in IMC and in close ground proximity.
              Live, from a grassy knoll somewhere near you.

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              • #22
                Originally posted by guamainiac View Post
                Good clarity, not a flame at all, thanks ... unless our resident "Perfesser at Large" (Gabe), weighs in with half a chalkboard of equations?
                3WE's explanation was good enough for me.

                I can't even begin to imagine how someone with that much time would even attempt a slip being in IMC and in close ground proximity. [/QUOTE]
                Who said that he ATEMPTED a slip?

                As 3WE said before, it rather looks that the slip was the unwanted consequence of a poorly executed steep turn.

                In any event, I would ask how he even attempt a steep bank in an airliner, let alone in IMC. Which leads to the next question:

                Who said that they were in IMC? Or rathar, what if conditions were IMC? Maybe they were already below the clouds and with a good view of the ground around them and ahead.

                The report says that, in the conditions that they were, the runway might have been visible from the airplane before the turn, except that they were 90° off course and apparently not knowing it so they were looking for the runway in the wrong direction, and that's the reason why the runway was not in-sight. (in sight = visible + looking at it)

                --- 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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                • #23
                  ...I can't even begin to imagine how someone with that much time would even attempt a slip being in IMC and in close ground proximity. ...

                  ...In any event, I would ask how he even attempt a steep bank in an airliner, let alone in IMC....
                  I should not bring up Microsoft flight sim as much as I do- but dang it- one of the things that I think it can simulate is not having your head in the game, and right or wrong- that happens to airline pilots sometimes...and sometimes simultaneiously.

                  Have you ever noticed a difference in feel enroute versus on an approach or short final? Control inputs are often a lot crisper during those critical phases of flight- at least in my experience as a passenger and I guess even in my experience landing a 172.

                  So you are intercepting the localizer, and you realize you are late so you lay into your bank a bit harder than normal and realize you better go straight to the magical 30-degree limit...

                  Lay in a little too hard and a momentary lapse in attention, and maybe you even decide to cheat a little and next thing you know, you are at 50 degrees...

                  ...did I say momentary lapse in attention?

                  ...so the nose is dropping and maybe you are slipping and the nose is dropping more and you are already pretty low anyway.

                  This is really terrible to say- but flying IFR with MSFS with a beer open and no copilot, and thinking "wow, dude, this is so cool"...I've learned just how quick you can be become a smoking hole in the ground...

                  I have learned that it's not really the beer that's the problem, it's the momentary lapse in attention.

                  Don't get me wrong- the lapse in attention is not ok- especially when it's a dual lapse (and no, beer is not OK)...just saying it doesn't take very long.

                  Oh crap, I missed it when the needle came alive and I'm flying through the Localizer...bank hard! Gotta get ready to land, where's the checklist, where's the tower freq...
                  Les règles de l'aviation de base découragent de longues périodes de dur tirer vers le haut.

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                  • #24
                    Originally posted by Gabriel View Post
                    I've said it n times, but here it goes again. In a stall (or even near one) there is a serious degradation of the roll damping and of the aileron effectiveness. Not a good combination. FIRST lower the AoA, THEN recover from the bank.
                    Isn't this where it is best to use the rudder (gently) to control roll and get the nose down?

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                    • #25
                      Originally posted by Evan View Post
                      Isn't this where it is best to use the rudder (gently) to control roll and get the nose down?
                      Please explain me the "rudder to get the nose down" part.

                      Lesson 1:
                      Elevator controls AoA, ailerons control roll, rudder controls sideslip.

                      Bear in mind that between the "FIRST" and the "THEN" above there is just a split second.

                      EDIT: Oh, it was a joke!? You forgot the blue font.

                      --- 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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                      • #26
                        3WE, the part where you confuse me is where you seem to causatively link the slip with the nose going down (in that cause-effect order).

                        Example from your last post, but there were others.

                        Originally posted by 3WE View Post
                        ...so the nose is dropping and maybe you are slipping and the nose is dropping more

                        --- 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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                        • #27
                          Originally posted by Gabriel View Post
                          3WE, the part where you confuse me is where you seem to causatively link the slip with the nose going down (in that cause-effect order).

                          Example from your last post, but there were others.
                          Until I use the word "causes", your argument is speculative, unsubstantiated parlour talk.
                          Les règles de l'aviation de base découragent de longues périodes de dur tirer vers le haut.

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                          • #28
                            Originally posted by Gabriel View Post
                            Please explain me the "rudder to get the nose down" part.

                            Lesson 1:
                            Elevator controls AoA, ailerons control roll, rudder controls sideslip.

                            Bear in mind that between the "FIRST" and the "THEN" above there is just a split second.

                            EDIT: Oh, it was a joke!? You forgot the blue font.
                            Ummm...depending on the aircraft, the rudder is an important roll control during a stall/spin situation where the ailerons are comprimised.

                            ...and let's not forget that the rudder (on most airplanes) is a very decent roll control...(that thing called dihedral makes the roll happen). It ain't very coordinated and there will be some skidding and slipping.

                            Typically in a spin, it's kind of bad to apply 'corrective' aileron inputs- do it 'all' with the rudder (and elevators).

                            Also, threre's those hands-off landings folks make- the rudder provides all the directional control and power is used for vertical control.
                            Les règles de l'aviation de base découragent de longues périodes de dur tirer vers le haut.

                            Comment


                            • #29
                              Originally posted by 3WE View Post
                              Until I use the word "causes", your argument is speculative, unsubstantiated parlour talk.
                              I concede I have only circumstantial evidence, but people has been convicted based on circumstantial evidence alone if there is enough of it:

                              Originally posted by 3WE
                              But then to let the nose drop and not keep it coordinated and instead developing a big sink (the slip/sink is someting a bad pilot might commonly due but a good pilot really should not).

                              You make a steep turn, start side slipping and then the tail weathervanes you into a nose-down attitude.

                              Um...wrong...a slip is when the plane is not in a coordinated turn BUT INSTEAD is "sliding in and down"

                              ...so the nose is dropping and maybe you are slipping and the nose is dropping more
                              But the most important thing is that you don't realize that, other things left equal, the nose will go lower if you keep it coordinated than if you leave it slip. On the other hand, if you put too much rudder and make a skid, the nose will go lower than if coordinated (again, everything else left equal).

                              Take this sentence and think a bit about it.

                              You make a steep turn, start side slipping and then the tail weathervanes you into a nose-down attitude.
                              (Note: coordinated means already weathervaned).
                              (Note 2: Imagine you are in a coordinated left turn an you apply right rudder. Are you now slipping or skidding? Does the nose go down or up?)

                              --- 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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                              • #30
                                Originally posted by 3WE View Post
                                Ummm...depending on the aircraft, the rudder is an important roll control during a stall/spin situation where the ailerons are comprimised.
                                I know that school. And I don't agree. Use rudder for roll control at / near stall at your risk. It's a recipe to turn a stall into a spin.

                                My stake is, if the ailerons are compromised because of a stall, then undo the stall and uncompromise the ailerons so they are effective to control roll. It's not like "oh, no I have to wait to recover from the stall to use the ailerons?!?!?". No. With the same hand, push the yoke (or releave back pressure) and twist it in the desired direction.

                                Typically in a spin, it's kind of bad to apply 'corrective' aileron inputs- do it 'all' with the rudder (and elevators).
                                In as spijn the rudder is NOT used to control roll. It's to control sideslip (or in fact skid). Actually, the procedure for spin recovery is "rudder opposite to rotation" (not to bank) and when you are confused about what pedal to press it is "step on the ball".

                                By the way, the second element of spin recovery is ELEVATOR NOSE DOWN!!! to recover from the stall. In fact, if you can recover from the stall with elevator alone, the airplane will stop spinning buy itself. But if you use rudder alone and keep full up elevator, you will not recover from the spin or you'll change form spinning in one direction to the opposite, or, the best outcome, is that you'll be fighting a unstable plane correcting every time it tries to enter a spin to one side or another. I'm sure you've heard "no stall, no spin".

                                Oh, by the way, the third step in spin recovery, after you've recovered from the stall and the plane stopped its rotation, is "recover from the dive" (with caution to prevent a secondary stall). This is the part that includes leveling the wings. Oh, I forgot, using AILERONS, not rudder.

                                Also, threre's those hands-off landings folks make- the rudder provides all the directional control and power is used for vertical control.
                                Yes, the rudder is an alternative mean to control roll in case you've lost your ailerons. Please, try to do it with a margin away from the stall.

                                --- 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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