Page 3 of 5 FirstFirst 12345 LastLast
Results 41 to 60 of 99

Thread: BREAKING: Boeing 767 cargo jet operated by Atlas Air has crashed in Texas

  1. #41
    Member
    Join Date
    Sep 2017
    Location
    Los Angeles
    Posts
    107

    Default

    Quote Originally Posted by Gabriel View Post
    With that I would start the speculation:
    - Murdecide
    - Trim runaway
    - Severe multiple hydraulic systems failure
    - Control cables to the elevator severed (the elevator is hydraulically actuated but I believe that the servo valves are located in the tail and controlled with the yoke via mechanical cables that run under the cabin floor).
    - Any of the last 2 may have been caused by an uncontained engine failure.
    - Movable stabilizer failure (like Alaska's MD-80).
    Is an unexpected cargo shift worthy of adding to the list?

    Admittedly pretty unlikely at this phase of the flight. But perhaps a gentle nose-down action could have initiated a slide if it were inadequately secured?

  2. #42
    Senior Member 3WE's Avatar
    Join Date
    Jan 2008
    Posts
    5,061

    Default

    Quote Originally Posted by flashcrash View Post
    Is an unexpected cargo shift worthy of adding to the list?
    Yes.

    That and a meteor strike.
    Les règles de l'aviation de base découragent de longues périodes de dur tirer vers le haut.

  3. #43
    Senior Member Gabriel's Avatar
    Join Date
    Jan 2008
    Location
    Buenos Aires - Argentina
    Posts
    6,971

    Default

    Quote Originally Posted by flashcrash View Post
    Is an unexpected cargo shift worthy of adding to the list?

    Admittedly pretty unlikely at this phase of the flight. But perhaps a gentle nose-down action could have initiated a slide if it were inadequately secured?
    Could be. It would need to be huge shift of a huge load to be not correctable with elevator+trim. Even in the famous 747 crash captured on video where some super heavy armored vehicles shifted a lot back on take off, the investigation revealed that the plane would have been controllable had the control system not been damaged when the vehicles crashed with the inner back of the plane.

    As you say, unlikely. But what in my list is not unlikely? Nd believe, whatever it was, even if not listed, it will be something that would be categorized as unlikely a priori.

    --- 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 ---

  4. #44
    Member
    Join Date
    Sep 2017
    Location
    Los Angeles
    Posts
    107

    Default

    Quote Originally Posted by Gabriel View Post
    Could be. It would need to be huge shift of a huge load to be not correctable with elevator+trim.
    Do we have any info on take-off weight? If low enough, we could potentially eliminate cargo shift from consideration.

  5. #45
    Senior Member 3WE's Avatar
    Join Date
    Jan 2008
    Posts
    5,061

    Default

    Quote Originally Posted by flashcrash View Post
    Do we have any info on take-off weight? If low enough, we could potentially eliminate cargo shift from consideration.
    I rank your weight shift as a real low likelihood, and believe that FDR data on control inputs + CVR will yield some sort of OTHER catastrophic control failure or one of the pilots pushing over due to something mental...

    ...and that this will happen BEFORE we can review whether there was enough weight and type of stuff to shift forward.

    Repeating Gabe's comment: The aero-engineers said that the Bahrain 747 was still flyable after the tank broke loose and rolled back...unfortunately, it jammed the elevators full up when it hit the back wall.

    Hard to fathom that a pallet of Amazon stuff is going to force a sudden steep dive like that.

    As long as we are speculating about everything and wild theories, there may have been some flap selection that took place and triggered something (no idea what, though).
    Les règles de l'aviation de base découragent de longues périodes de dur tirer vers le haut.

  6. #46
    Member
    Join Date
    Jan 2009
    Posts
    252

    Default

    Quote Originally Posted by Gabriel View Post
    Could be. It would need to be huge shift of a huge load to be not correctable with elevator+trim. Even in the famous 747 crash captured on video where some super heavy armored vehicles shifted a lot back on take off, the investigation revealed that the plane would have been controllable had the control system not been damaged when the vehicles crashed with the inner back of the plane.

    As you say, unlikely. But what in my list is not unlikely? Nd believe, whatever it was, even if not listed, it will be something that would be categorized as unlikely a priori.
    Thanks Gabriel. I never read that 747 report until now. I think all the discussion about that accident is extremely misleading. The weight shift really wasn't much of a contributer at all. The bloody vehicle punctured the rear pressure bulkhead before the plane was even off the ground rupturing hydraulics and bending the horizontal stabilizer assembly in the back. The uncommanded movement of the horizontal stabilizer caused the pitch up and subsequent stall and crash. Wikipedia's description of the event is incorrect as it blames the weight shift for the pitch up and loss of control.

    What is sad is that the crew discussed the load shift in the prior flight segment and hoped the loadmaster was rectifying it.

  7. #47
    Member
    Join Date
    Feb 2009
    Posts
    103

    Default

    Quote Originally Posted by B757300 View Post
    A much clearer video of the aircraft has been released. This is the video footage that was mentioned during the first NTSB press conference.

    https://www.khou.com/article/news/lo...b-e9ea9e9abbf6

    https://www.click2houston.com/news/n...in-trinity-bay

    https://www.youtube.com/watch?v=-GeQycmuco4

    I watched the 'youtube' clip first, about 3x then I watched the C2Houston clip twice and I immediately 'pondered' if the a/c 'nosedive' towards the last few moments wasn't lessening in nose down attitude, that is to say, it seemed to be more towards 'leveling out' than the first few moments.

    Then I watched the KHOU clip and interestingly one of the commentators mentioned that some avation folks had perhaps noticed the same thing.

    I only mention this b/c while I'm not a pilot/ATC - that 'lessening of pitch down' was (or seemed) very evident to me (a lay person) immediately in the first Ytube clip viewing . . . and if a layperson (me) sort of sensed it (as it seems others have) maybe there's something to that notion. Maybe.

  8. #48
    Member
    Join Date
    Feb 2009
    Posts
    103

    Default

    Quote Originally Posted by B757300 View Post
    Saw this mentioned on Twitter.

    Listen to it when ATC received an "Ok" from the pilot. Instantly after the "ok" it sounds like there is a GPWS "PULL!" audible in the background. I've listened to it about 30 times (using ear buds) and it does sound to me like a "PULL" is heard, but maybe its a case of having the thought already planted in my head so I hear what I'm expecting. Occurs right around the 8:40 mark.

    Hi B757 & Gabriel . . .

    While I likely can't discern a pickle switch from a pitch trim wheel . . . I am somewhat 'nifty' with audio files. Rather nifty. So I listened to the ATC track you mentioned and I have some 'curiosities' - things that caught my ear -however due to my general piloting/ATC 'know not muchness' I am unable to discern if my 'curiosities' are valid or just totally off the mark.

    The reason specifically is that I'm not entirely sure in the series of communications <9:00 exactly who is who in each case. I'm wondering if you (or Gabriel) would be able to help me out in that regard so that I 'know' confidently what (whom) I'm listening to. Before timepoint let's say 9:00 . . . I need to know which 'coms' are the incident a/c (to ATC) and which are ATC to Atlas.

    I can identify some of them (including the '8:40' spot mentioned) but I need to know the other Atlas air/ATC coms before that 8:40 mark (and any after..I dont think there are any). I don't need much more than a roadmap such as (and this is totally made up):

    6:15 ATC to Atlas altitude clearance
    6:18 Altas readback/confirm
    6:40 Atlas to ATC weather inquiry
    6:56 ATC to Atlas course change instruction


    With all the other a/c and 'stuff' going on I can't be sure of who IS Atlas in each of their coms and when ATC coms with them each time (honestly I never can figure out how y'all can talk so fast with so many others and have any clue which what is what (my eternal respect that you can sort it all out!). But for the waveform analysis, I need to know each of their coms (again, ATC to Atlas and vice versa).

    The 'pull up' might not be the only 'hmmm' question - I've definitely got some curiosities but need a helping hand to be sure I know who is who. If you or someone else have a few minutes to write me a 'coms roadmap' as above.

    Thanks!

  9. #49
    Member
    Join Date
    Feb 2009
    Posts
    103

    Default

    Belay my aforementioned request, after listening to the ATC audio loop about 10x I've figured most of it out and extracted the stuff I need.

    But sheesh, you aviator / ATC folks don't make it easy for us mere mortals who are limited to non-jet speed speaking and understanding!

  10. #50
    Senior Member Gabriel's Avatar
    Join Date
    Jan 2008
    Location
    Buenos Aires - Argentina
    Posts
    6,971

    Default

    It is not easy for me either. This might help: https://www.youtube.com/watch?v=0cn58iVuzBY

    --- 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 ---

  11. #51
    Senior Member Gabriel's Avatar
    Join Date
    Jan 2008
    Location
    Buenos Aires - Argentina
    Posts
    6,971

    Default

    NTSB update:

    Radar data indicated the airplane continued the descent through 12,000 ft with a ground speed of 290 knots, consistent with the arrival procedure. The pilots responded that they wanted to go to the west of the area of precipitation. The controller advised that to do so, they would need to descend to 3,000 ft expeditiously.

    About 12:37, the controller instructed the pilots to turn to a heading of 270°. Radar data indicated the airplane turned, and the automatic dependent surveillance-broadcast (ADS-B) data indicated a selected heading of 270°. The airplane was descending through 8,500 ft at this time.

    About 12:38, the controller informed the pilots that they would be past the area of weather in about 18 miles, that they could expect a turn to the north for a base leg to the approach to runway 26L, and that weather was clear west of the precipitation area. The pilots responded, “sounds good” and “ok.” At this time, radar and ADS-B returns indicated the airplane levelled briefly at 6,200 ft and then began a slight climb to 6,300 ft.

    Also, about this time, the FDR data indicated that some small vertical accelerations consistent with the airplane entering turbulence. Shortly after, when the airplane’s indicated airspeed was steady about 230 knots, the engines increased to maximum thrust, and the airplane pitch increased to about 4° nose up and then rapidly pitched nose down to about 49° in response to column input. The stall warning (stick shaker) did not activate.

    FDR, radar, and ADS-B data indicated that the airplane entered a rapid descent on a heading of 270°, reaching an airspeed of about 430 knots. A security camera video captured the airplane in a steep, generally wings-level attitude until impact with the swamp. FDR data indicated that the airplane gradually pitched up to about 20 degrees nose down during the descent.

    --- 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 ---

  12. #52
    Senior Member Evan's Avatar
    Join Date
    Jan 2008
    Posts
    6,693

    Default

    Quote Originally Posted by Gabriel View Post
    NTSB update:
    Shortly after, when the airplane’s indicated airspeed was steady about 230 knots, the engines increased to maximum thrust, and the airplane pitch increased to about 4° nose up and then rapidly pitched nose down to about 49° in response to column input.
    So, full thrust and sustained full forward column commands?
    Did somebody take a trip to the lav?

  13. #53
    Member orangehuggy's Avatar
    Join Date
    Jan 2008
    Posts
    406

    Default

    NTSB messed up here and quickly changed its statement from:

    …the airplane pitch increased to about 4° nose up and then rapidly pitched nose down to about 49° in response to column input.

    to:

    …the airplane pitch increased to about 4° nose up. The airplane then pitched nose down over the next 18 seconds to about 49° in response to nose-down elevator deflection.

    Big difference!
    moving quickly in air

  14. #54
    Senior Member Evan's Avatar
    Join Date
    Jan 2008
    Posts
    6,693

    Default

    Quote Originally Posted by orangehuggy View Post
    NTSB messed up here and quickly changed its statement from:

    …the airplane pitch increased to about 4° nose up and then rapidly pitched nose down to about 49° in response to column input.

    to:

    …the airplane pitch increased to about 4° nose up. The airplane then pitched nose down over the next 18 seconds to about 49° in response to nose-down elevator deflection.

    Big difference!
    Uh, yeah.

  15. #55
    Senior Member 3WE's Avatar
    Join Date
    Jan 2008
    Posts
    5,061

    Default

    Quote Originally Posted by Evan View Post
    Uh, maybe.
    Fixed.

    (Don't be so black and white).
    Les règles de l'aviation de base découragent de longues périodes de dur tirer vers le haut.

  16. #56
    Senior Member B757300's Avatar
    Join Date
    May 2003
    Location
    CLL
    Posts
    1,374

    Default

    A theory I saw posted on another forum by a 767 pilot was that this may be similar to China Airlines 140, an inadvertent activation of the TOGA system, and then the crew did not respond correctly to it.

    Just a theory, but thought I'd post it here to see what everyone else thinks.

  17. #57
    Senior Member Gabriel's Avatar
    Join Date
    Jan 2008
    Location
    Buenos Aires - Argentina
    Posts
    6,971

    Default

    Quote Originally Posted by B757300 View Post
    A theory I saw posted on another forum by a 767 pilot was that this may be similar to China Airlines 140, an inadvertent activation of the TOGA system, and then the crew did not respond correctly to it.

    Just a theory, but thought I'd post it here to see what everyone else thinks.
    I don't think so.

    I believe that in the 767 (actually I believe that all airplanes including now, after a mod, the A300 as the one involved in that accident) the AP disconnects if you make more than a certain threshold force in the controls.

    --- 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 ---

  18. #58
    Senior Member 3WE's Avatar
    Join Date
    Jan 2008
    Posts
    5,061

    Default Question to Bobby / VNavV / ATL:

    Several folks have offered up a "disorientation" theory...with that $20 Somgraphicalillusionary word...

    That's fine and all, but I thought that "upset recovery" and/or "unusual attitude" recovery was something that was practiced maybe yearly?...

    ...and is a skill that goes waaaaaaaay back to basic instrument stuff (maybe even the basic private pilot stuff)and all sorts of recurrent checks and trainings and such...

    ...and is not sooo complicated that you'd really forget it...

    The single question is "How often do you practice unusual attitude recovery"

    Thanks.
    Les règles de l'aviation de base découragent de longues périodes de dur tirer vers le haut.

  19. #59
    Senior Member BoeingBobby's Avatar
    Join Date
    Jun 2009
    Location
    MIA
    Posts
    1,412

    Default

    [QUOTE=3WE;

    The single question is "How often do you practice unusual attitude recovery"

    Thanks.[/QUOTE]

    Answer to your question is every other simulator session, so once a year.

    Sorry but I am not at liberty to discuss this accident. I am sure you will understand.

  20. #60
    Junior Member
    Join Date
    Jul 2013
    Posts
    92

    Default

    Any more news from the NTSB on this crash?

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •