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Gulfstream IV jet ran off a runway while taking off

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  • All control surfaces are hydraulically actuated. Here is an excellent website about the G-IV written by a G-IV driver. Here you will find all you want to know...

    If it 'ain't broken........ Don't try to mend it !

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    • Originally posted by brianw999 View Post
      All control surfaces are hydraulically actuated.
      Mechanically actuated and hydraulically boosted to be exact.

      This stab trim gearbox interaction with the flap setting is interesting:

      The stabilizer is automatically adjusted when the flap setting is changed in order to compensate for changes in trim caused by flap extension and retraction. The stabilizer is moved via a gearbox in the tail. The flap gearbox is connected to the gearbox in the tail. The stabilizer position is indicated by a gauge within the flap position indicator. If the stabilizer does not position itself properly with each change in flap setting, return to the previous setting and go to the checklist. The aircraft may be landed safely with the stabilizer out of trim, however, much higher than normal control forces may be required, as the trim will not be as effective.
      Great site by the way.

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      • The National Transportation Safety Board released more than 800 pages from its accident investigation docket that reveal troubling clues about what may have caused last May’s crash of a Gulfstream IV in Bedford, Massachusetts, which killed seven people on board including Philadelphia Inquirer owner Lewis Katz. The most disquieting information contained in the trove of … Continued


        The National Transportation Safety Board released more than 800 pages from its accident investigation docket that reveal troubling clues about what may have caused last May's crash of a Gulfstream IV in Bedford, Massachusetts, which killed seven people on board including Philadelphia Inquirer owner Lewis Katz.

        The most disquieting information contained in the trove of data centers on ignored preflight checks of the flight controls by the pilots, as well as a potentially crucial warning message that wasn't heeded.

        The Gulfstream crashed into a gully almost 2,000 feet off the end of the runway last May 31 and burst into flames after the pilots discovered the elevator was locked as they reached a speed of 165 knots during the attempted takeoff.

        Data from a recorder installed in the airplane showed that in the previous 176 takeoffs, full flight control checks as called for on the GIV's checklist were carried out only twice and partial checks only 16 times. The pilots on the evening of the accident skipped the flight control check, which might have revealed to them that the gust lock mechanism was still engaged.

        Another crucial clue could be a warning message for "rudder limit," which the pilots briefly discussed just prior to takeoff but then ignored.

        NTSB tests show that had the pilots applied reverse thrust and full braking the moment they realized the elevator control was locked, they could have aborted the takeoff with runway to spare.

        The data released by the NTSB this week isn't meant to assign blame or list a cause of the crash, but rather to provide insight into the final moments leading to the tragedy. The Board's final accident report is due out later this year.

        Read more at http://www.flyingmag.com/technique/a...juUedEJ74G8.99
        NTSB's docket:

        --- 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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        • The CVR on this one doesn't contain a single shred of evidence that any checklists were completed whatsoever. Nothing for After Start, Taxi, or Before Takeoff. It was literally...start 'em up and let's blast off!

          I have no experience in the world of Corporate flying, but this really seems like the wild west.
          Parlour Talker Extraordinaire

          Comment


          • Originally posted by 3WE
            Stupid question here...

            ...these things don't have control locks, do they?
            Not such a stupid question after all. 3WE wins this round of Parlour Talkin' Investigation. Gabriel, tell him what he's won...

            But, actually, the real cause of this crash was lack of p r o c e d u r e . . .

            Comment


            • Originally posted by Evan View Post
              Not such a stupid question after all. 3WE wins this round of Parlour Talkin' Investigation. Gabriel, tell him what he's won...

              But, actually, the real cause of this crash was lack of p r o c e d u r e . . .
              But, my 172 POH checklist has an item called "Controls, free and correct"...and on most airliner rides I see the spoilers flap up and down on taxi...

              ...seems like a good, broadly applicable fundamental to me.

              Maybe the pilots were overly focused on fancy type specific computer stuff like cryptic FMS programming or auto throttle modes?
              Les règles de l'aviation de base découragent de longues périodes de dur tirer vers le haut.

              Comment


              • Originally posted by 3WE View Post
                Maybe the pilots were overly focused on fancy type specific computer stuff like cryptic FMS programming or auto throttle modes?
                I think in some cases that is certainly an issue, but I'm not sure it was in this case. Looking at the CVR transcript it doesn't appear the pilots were focused on much of anything.

                I vote pure-and-simple complacency, possibly with a bit of tiredness.
                Be alert! America needs more lerts.

                Eric Law

                Comment


                • Originally posted by Evan View Post
                  But, actually, the real cause of this crash was lack of p r o c e d u r e . . .
                  What procedure do you think should have been in place that was not already there?
                  Be alert! America needs more lerts.

                  Eric Law

                  Comment


                  • Originally posted by elaw View Post
                    What procedure do you think should have been in place that was not already there?
                    ...to note if your upward pointing thumb is aiming left or right as you crank the wheel...

                    I'm not sure I've ever seen that on a checklist yet, I generally always used it.

                    ...and I recall a very chilling, relevant and close-to-home In The Shade story.
                    Les règles de l'aviation de base découragent de longues périodes de dur tirer vers le haut.

                    Comment


                    • Originally posted by elaw View Post
                      I think in some cases that is certainly an issue, but I'm not sure it was in this case. Looking at the CVR transcript it doesn't appear the pilots were focused on much of anything.
                      One minute, you know that you are just a parlour-talking ass-hat on an obscure aviation forum that falls well short of the true knowledge or skill that it takes to fly any sort of commercial jet.

                      Then you read stuff like this and say, "wow", it sure goes against what I was taught in 172 school...

                      ...and you just can't come up with a decent explanation other than somehow, they forgot and/or ignored some of the most basic rules.
                      Les règles de l'aviation de base découragent de longues périodes de dur tirer vers le haut.

                      Comment


                      • Wow...gross

                        Comment


                        • NTSB final report on this is available: http://www.ntsb.gov/investigations/A...ts/AAR1503.pdf
                          Be alert! America needs more lerts.

                          Eric Law

                          Comment


                          • Any recommendations for the establishment of V3 speeds, where you abandon the takeoff past V1/V2, brake hard, and run off the end for a survivable crash as opposed to continuing until it's too late?
                            Les règles de l'aviation de base découragent de longues périodes de dur tirer vers le haut.

                            Comment


                            • I haven't read all the way through the report yet but I have found one very interesting thing in there. It appears in this case that V1 wasn't actually V1!

                              As I understand it, V1 is the speed above which the takeoff cannot successfully be aborted. Presumably "successfully" in this case means without causing an accident.

                              In this case during the takeoff sequence (per the report), the "V1" call was made and about 1-1/2 seconds later the "rotate" call was made. The phrase "lock is on" is heard on the CVR about 1 seconds after the "rotate" call - that presumably represents the first time the pilot(s) identified the fact the gust lock was engaged.

                              But here's the good part, from page 48 of the report:
                              Originally posted by NTSB report
                              The airplane performance study determined that, if the flight crew had initiated a rejected takeoff in accordance with the G-IV AFM at the time of the PIC’s first “lock is on” comment or at any time up until about 11 seconds after this comment, the airplane could have been stopped on the paved surface.
                              So basically they're saying that up to about 13 seconds after the "V1" call, the takeoff could have been aborted safely. Or in other words, the aircraft's speed and distance down the runway when "V1" was called did not conform to the meaning of "V1".

                              IMHO taking that into account, the concept of a "V3" speed where an abort could be made with a possibly-survivable crash doesn't pertain to this accident. Instead, the pilots presumably thought the takeoff could not be aborted safely when the gust lock was found engaged since that happened after the V1 call which by definition means a safe abort is no longer possible. Yet in this case per the NTSB data, a safe abort *was* possible... and if the pilots had known that, the outcome quite likely would have been different.
                              Be alert! America needs more lerts.

                              Eric Law

                              Comment


                              • Originally posted by elaw View Post
                                ...As I understand it, V1 is the speed above which the takeoff cannot successfully be aborted...
                                I am a routine offender of taking a fuzzy concept and then, as a layman, thinking that's exactly what it means, only to learn later, that I'm wrong.

                                I'm pretty sure that there's a lot of smaller, lightly-loaded airliners on 14,000 ft runways (at Denver and many other places) that almost always make V1 calls, even though there's adequate stopping distance through V2...

                                Although, you just brought up a frightening "established procedure" versus "fundamental" versus "reality" conflict.

                                The procedure- which is done over and over and over is to calculate V1 and make a go-no-go decision.

                                The broad, general fundamental is that aborting after V1 has resulted in too many crashes where it would have been better to continue (versus the converse situation).

                                But, it would seem that in this case, there was a V3P (I use that term jokingly) where you could abort after V1 and stop safely and remain on pavement...

                                Yet, I don't think there's many procedures anywhere where pilots calculate and brief on a past-V1-but-still-safe-to-abort speed....
                                Les règles de l'aviation de base découragent de longues périodes de dur tirer vers le haut.

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