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747 fails to climb after VR engine failure

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  • 747 fails to climb after VR engine failure

    I want to summon our resident 747 pilot (or pilots?) to see what you think of this incident.
    Although the incident was real, there are several things that look suspicious to me (not the smallest of which is that a 747 should have zero problem climbing out on 3 engines at sea level) that makes me think that the story as told in this video (on in the Wikipedia article, which is basically the script used for the video) is missing some things or getting things wrong.

    Unfortunately I could not find better references.

    https://www.youtube.com/watch?v=qaYp3jUiPzc

    --- 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 ---

  • #2
    Haven't a clue. Sounds a little fishy to me. But I also never flew a water wagon 74 either. Maybe Kent has and will chime in.

    Comment


    • #3
      Originally posted by Gabriel View Post
      I want to summon our resident 747 pilot (or pilots?) to see what you think of this incident.
      Although the incident was real, there are several things that look suspicious to me (not the smallest of which is that a 747 should have zero problem climbing out on 3 engines at sea level) that makes me think that the story as told in this video (on in the Wikipedia article, which is basically the script used for the video) is missing some things or getting things wrong.

      Unfortunately I could not find better references.

      https://www.youtube.com/watch?v=qaYp3jUiPzc
      Referring to that video, I wonder if the sudden switch from a 747-200 to a 747-8 could have been too much for the #3 engine...

      That aside, I see two possibilities:
      A) It never happened. There IS a wikipedia article on it that appears to have been written by the person who made the video.
      B) It happened with significantly different factual circumstances.

      Some of the old JT9D classics were significantly underpowered. Water/Methanol injection was an option on some. It was controlled by the FE but the pilots had 4 indicator lights on the forward panel. There was a procedure to follow that included a "water on" callout prior to advancing thrust levers. The system was not so reliable so the crew had to keep an eye on things for the 2-3 minutes in which it operated. If Capt. Sifis Migadis was some kind of sky god and the story went as told in the video, he was having a senior moment that day...

      Why the engine failure? One possibility is that the water injection was properly activated but the #3 water valve (spring-loaded) malfunctioned and closed. Activation of the system also set fuel flow to a higher level. If the water cut off early, the EGT went north beyond limit and the engine could subsequently go south. Crews were trained to monitor EGT closely when using the system. If this occurred, the FE might have gotten a water pressure warning light but I don't know for certain.

      Why the limited climb performance? As I said, these aircraft were underpowered to begin with. Then the water injection system added a good deal of weight, adding two water tanks into the wings. Perhaps that extra weight was somehow not accounted into the MTOW used by the crew? Also, it is deadweight if the system isn't turned on. But even so, I cannot accept that any 747 could have been certified without engine-out climb performance at MTOW that includes a good margin of error. That said, I remember reading some memiors of a former KC-135 pilot who recalled how underpowered the pre-water-injection aircraft were, and how white knuckle takeoffs were sort of SOP. But on the 747/JT9D, the water-injection only added about 2000 lbs thrust per engine. That would be a very thin margin between climb and no-climb performance during certification.

      As to the performance of the pilot, well, he seems to have failed to monitor if it was inactivated. Once airborne, I think the first move should have been to lose TOW by dumping the water tanks. There is a dump switch on the FE panel and it was SOP to dump after EVERY takeoff when using the system.

      I think it's probably an internet fiction, or it not, a very flawed account of what actually happened.

      Comment


      • #4
        'Referring to that video, I wonder if the sudden switch from a 747-200 to a 747-8 could have been too much for the #3 engine..."

        Is this supposed to be a joke?


        Jibber jabber from Evan as usual. Wait for it, here comes LH's story!

        Comment


        • #5
          Originally posted by BoeingBobby View Post
          'Referring to that video, I wonder if the sudden switch from a 747-200 to a 747-8 could have been too much for the #3 engine..."

          Is this supposed to be a joke?
          I got lazy about procedure. Fixed.

          Comment


          • #6
            Pretty sure the -8 was only used for the video being that this happened over 20 years before the -8 was built!

            Comment


            • #7
              Originally posted by BoeingBobby View Post
              Pretty sure the -8 was only used for the video being that this happened over 20 years before the -8 was built!
              I think it has to do with a certain lack of basic aviation knowledge, or maybe that was the only 3D model on hand. I seem to recall that Tarantino's film Once Upon a Time in Hollywood made a simlilar CGI 'mistake', using a 747-400 for a 1970's Pan Am flight.

              Comment


              • #8
                The video started showing a -200 for the intro and then switched to the -8, possibly doe to what was available in the PC sim that the youtuber was using. Hence the joke (nobody said it was a funny joke, but it's time to get over it).

                I think that taking off from a closed runway may have been a factor. Who knows what kind of FOD you can have when operating from a closed runway [/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 ---

                Comment


                • #9
                  Originally posted by Evan View Post

                  I think it has to do with a certain lack of basic aviation knowledge
                  Finally something you are an expert on!

                  Comment


                  • #10
                    I only flew the -100 and -200 with no water injection. Max takeoff weights where 734,000 and 750,000 for the old ones and 800,000 for the -200's. Even at a max weight takeoff the rate of climb was nothing to write home about. We used a reduced climb power up to about Fl 230 so even the climb was slow. I think I would have retracted the gear as well.

                    I remember a United flight taking off from SFO to the west. Lost one engine and the pilot didn't use any rudder. If you've been to SFO you remember the hill just to the right, they missed it by 50ft.

                    Comment


                    • #11
                      Originally posted by kent olsen View Post
                      I remember a United flight taking off from SFO to the west. Lost one engine and the pilot didn't use any rudder. If you've been to SFO you remember the hill just to the right, they missed it by 50ft.
                      I've NEVER flown that SID during a PC in the simulator in my life I swear!

                      Comment


                      • #12
                        Back to the thread topic: Wanton, unsubstantiated parlour talk: Perhaps the engine did shed some parts violently, and in the process screwed up some other important stuff.

                        There was that Brasilia that shed a prop blade, and the imbalance/vibration jerked the engine markedly sideways and screwed things up (drag) enough that the airplane could not hold altitude enough to make an airport. In Gabie's incident, if we boogered an adjacent engine or a slat/flap/cowling, that could cut the performance even more.

                        Finally, back off topic in an attempt at some plain language: Dudes are making lots of YouTubes these days, and using a 'toy' flight sim, grab anything that sort of resembles the actual plane and then halfway flying the flight of the actual flight path, trying to give us a SIMULATED OVERVIEW of ROUGHLY what happened...

                        So, we are watching a 787-8
                        00 SORT OF reenact an incident with a '-200.

                        And, Evan made a joke that the '8
                        00 was the problem. He is a horrible black and white thinker with no appreciation for human behavior and bike riding, but he does have a reasonable sense of humor...his joke was relevant and worth a half-cocked grin.
                        Les règles de l'aviation de base découragent de longues périodes de dur tirer vers le haut.

                        Comment


                        • #13
                          Originally posted by 3WE

                          And, Evan made a joke that the '8 was the problem.
                          What are you talking about. I was dead serious. I’ll leave the material expansion equations of going from a JT9D to a GEnx in a matter of seconds to Gabriel, but it’s gotta hurt. More importantly, you start rolling down the runway and -BANG- your flight engineer is just gone. That HAS to be distracting, especially when trying to rotate a 747-8 from a runway in 1978. Although, indeed, it might produce an unintentional half-cocked grin.

                          Comment


                          • #14
                            Originally posted by Evan View Post
                            especially when trying to rotate a 747-8 from a CLOSED runway in 1978.
                            Fixed


                            --- 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


                            • #15
                              Originally posted by Gabriel View Post
                              Fixed
                              Noted.

                              Any further speculation on why a 747-200 with JT9D's and water injection won't climb after engine failure? Or did this never happen? Or should we stick to bad jokes?

                              Comment

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