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Polish President and wife killed in Tu-154 crash

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  • Originally posted by Evan View Post
    uh, speaking of dyslexic...

    QFE is the altimeter setting to display altitude above field elevation (I'm sure you just typed that in wrong).
    Oops. Of course.

    I've been told that RadAlts are notoriously erratic, and exist mostly for automation, and the terrain may have been quite uneven there, so maybe they based their glide slope on the QNE information and disregarded the Radalt readings.
    Landing on QNE???

    AFAIK RadAlt readings are erratic over uneven terrain, trees or bulidings, but that "erraticity" is of the oreder of magnitude of those features.

    That is, not significative you are supposed to reamin at the MDA (typically about 400ft AGL)

    Also, I think the Radalts were recent upgrades on this plane, so they probably weren't accustomed to relying on them.
    Point.

    --- 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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    • Originally posted by Evan View Post
      According to Google Earth, the airfield threshold is about 835ft elevation, but the point where the first impact occurred is about 100 ft lower elevation, which means they were below the airfield elevation when they impacted the trees. The final approach to the runway involves overflying a ravine that drops to about 680ft elevation. So Radalt information would be fairly useless if the field elevation were not calibrated correctly.
      I disagree. RadAlt information would have prevented the crash, even if would be not usefull to keep a precise MDA.

      You see... you crash when RadAlt is zero (or 66ft if you hit the top of an antena that high).

      If the airfield is 835ft and, for the sake of the argument, the MDA is 1235 ft, that's 400ft above the runway. Keeping 400ft AGL you would "contour" the terrain with a variable altitude (QNH, QFE or QNE).

      When you fly over the 680ft ravine with 400 AGL you'll be at 1080. That's 155 ft below the MDA. Too bad, but still safely above obstacles.

      --- 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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      • Originally posted by Gabriel View Post
        Oops. Of course.


        Landing on QNE???
        And then I typed in QNE instead of QFE. Dyslexia fest.

        Comment


        • Originally posted by Gabriel View Post
          I disagree. RadAlt information would have prevented the crash, even if would be not usefull to keep a precise MDA.

          You see... you crash when RadAlt is zero (or 66ft if you hit the top of an antena that high).

          If the airfield is 835ft and, for the sake of the argument, the MDA is 1235 ft, that's 400ft above the runway. Keeping 400ft AGL you would "contour" the terrain with a variable altitude (QNH, QFE or QNE).
          I meant useless for finding the runway if you are not watching the pressure altimeter. The ground is going to come up on you at the last minute. Obviously they were busting the minimum, but if they were flying on the radalt alone and were not aware of the terrain issue, they would end up exactly as they did.

          Originally posted by Gabriel View Post
          When you fly over the 680ft ravine with 400 AGL you'll be at 1080. That's 155 ft below the MDA. Too bad, but still safely above obstacles.
          That ravine looks to be about 680ASL at the deepest point, and the threshold is about 830ASL, so the ravine goes to about FE-250ft. So with a correct QFE setting, flying at 400ft barometric, you would be at 650ft AGL (650ft RA).

          If you wanted to come in through that fog with a good visual contact with the terrain on final, and you were unfamiliar with the terrain, you might be at 200AGL over that ravine, but actually 50ft below the field altitude, and a moment later the ground comes back up in a hurry. You see what I mean? If you were watching the radio altitude and not the baro, you would mow into the trees before you knew what hit you.
          Last edited by Evan; 2010-04-17, 23:10. Reason: I just got it

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          • I've heard conflicting reports about this supposed antenna strike. I was trying to locate an antenna on the satellite imagery. The sun is low so even short objects are casting long shadows. A sizable antenna should cast a rather obvious shadow.

            I found something in the general area where the first strike occurred. It may be a ground anomaly. It's hard to say. It is the object in the yellow circle.

            There is another object around the area of the second impact. It could be a tree, but it appears grey and casts a deeper shadow than other trees around it. It is in the red circle.

            It they struck a 60ft antenna at the area of the yellow circle, they would have been flying at 720ASL (660+60ft).

            If they struck a 60ft antenna at the area of the red circle, they would have been flying at 875ASL (815+60ft).

            The field threshold elevation is 834ASL.

            **All this is based on Google Earth, so take it for what it is.

            Comment


            • Originally posted by Victor M View Post

              I guess all over the world the first reaction is to bust out the recording device and catch some gore if you can.
              I do work for a domestic US airline, and it should be noted that I do not represent such airline, or any airline. My opinions are mine alone, and aren't reflective of anything but my own knowledge, or what I am trying to learn. At no time will I discuss my specific airline, internal policies, or any such info.

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              • Originally posted by Evan View Post
                That ravine looks to be about 680ASL at the deepest point, and the threshold is about 830ASL, so the ravine goes to about FE-250ft. So with a correct QFE setting, flying at 400ft barometric, you would be at 650ft AGL (650ft RA).

                If you wanted to come in through that fog with a good visual contact with the terrain on final, and you were unfamiliar with the terrain, you might be at 200AGL over that ravine, but actually 50ft below the field altitude, and a moment later the ground comes back up in a hurry. You see what I mean? If you were watching the radio altitude and not the baro, you would mow into the trees before you knew what hit you.
                Evan,

                830 - 680 = 150, not 250.

                Anyway, if they intentionally descended more than 200ft below minumums, then I don't care anymore about QNH, radalt, or whatever. They were betting on a too stupid risk, and they lost. The MDA is the MINIMUM descent altitude for something.

                --- 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


                • Originally posted by Gabriel View Post
                  Evan,

                  830 - 680 = 150, not 250.
                  I can respect your opinion on that.
                  (such are my math skills at 3 am)

                  Regardless, if they were at 200AGL over the bottom of that ravine, they had a date with the treetops moments later.

                  My theory is that they considered it safer in those primitive conditions to establish visual contact with the runway as early as possible, and were coming in on a very low, shallow approach, making the most of their wonderful new radalt technology, believing they were maintaining a safe altitude for short final, but were unaware of the last-minute terrain issues.

                  -or- they were unaware of a certain structural obstacle.

                  -or- they encountered icing at this vulnerable stage.

                  I have searched in vain for a Jeppesen plate. I have found every other aerodrome in Russia, but not this one.

                  Comment


                  • Originally posted by Evan View Post
                    I've heard conflicting reports about this supposed antenna strike. I was trying to locate an antenna on the satellite imagery. The sun is low so even short objects are casting long shadows. A sizable antenna should cast a rather obvious shadow.
                    It could be the yellow one. Circa 1000 ft to the left of the centerline.

                    The other one isn't consistent with other shadows, it looks like a building.

                    Comment


                    • Not sure if it will help (I haven't cross checked the images) but here is what comes from wp.pl There is only mentioning of trees though. The first one 1050 m from the runway (nr. 1 in the second image), the next one approximately 200m further.
                      Pure speculation but image 6 in the second photo is probably the one that hit the left wing and made the plane turn on its left side.

                      Is it possible that the NDB is the antenna visible on image 2 in the second picture? (sorry for the noob question)

                      So, Evan, first impact seems to have been one diameter of the red/orange circle on your picture to the right (in the approach line) if I cross-check the pictures correctly.



                      Last edited by Geebee; 2010-04-18, 18:48. Reason: added reference to Evan's message

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                      • How many trees do I need to hit before realizing ' hmm maybe I'm too low!!' what a meathead pilot...sorry for the term but in this case u just have to be..

                        Comment


                        • Originally posted by dash88 View Post
                          How many trees do I need to hit before realizing ' hmm maybe I'm too low!!' what a meathead pilot...sorry for the term but in this case u just have to be..
                          Just one. Once that wing's damaged and not producing the lift to get you away there's nothing you can do. Remember, force = mass x acceleration - when you're talking about something with the mass of a fully loaded airliner, and the acceleration (upwards) needed to get you out of the trees, the force required is enormous. If nothing is producing that force, guess what - you're not accelerating upwards.

                          Sorry for the over simplification, but there it is.
                          Yet another AD.com convert!

                          Comment


                          • A few more elements were shared by the investigation commission. If I read it correctly, the assessment of the CVRs is almost finalized. Let's see first if that will happen. What was confirmed so far (apologies for the bad translation):
                            From the first findings of the investigation it is also known that the direct cause of the disaster was the plane hitting a tree. The machine lost part of the wing, changed the direction of flight and a big bow crashed into the ground. The pilots tried to lift the plane, but it was no longer able to respond.
                            So they never hit the NDB or any antenna. That appears to be confirmed.

                            Meanwhile, Mr. Seremet (Attorney General) made another press conference briefing about the progress made. As the Russians are leading the criminal investigation, no specific facts can really be made public. That includes 50 statements of witnesses interviewed so far (this does not mean 50 people who actually saw the accident, but also maintenance crew, etc.).
                            There are also at least 2 more official investigations. One by the Polish prosecutors and one by the Air Accident Investigation Committee. There may be more but that is not clear.

                            Although the prosecutors have clearly requested the public and the press to refrain from speculations and assessments by pseudoexperts (just quoting....) until all aspects of the accident have been fully investigated it is interesting to know that
                            Seremet stated that the office of the investigation is conducted its investigation towards unintentionally causing a plane crash, which resulted in death of man. This does not mean that it is the most probable cause of the disaster.
                            To be continued.

                            Comment


                            • http://www.thenews.pl/international/artykul129956_poland-presses-russia-to-pass-on-sm

                              So this is the latest I found. I do think this accident is some how a cause of Russian ignorance. I think that PAF 101 had good avionics and it probably was working. Doesn’t a warning kick on when they are to low like (danger low terrain, speed, stall some thing in front of you terrain) Those pilots wore one of the best and I don't think they would have made a mistake like this!! Some thing is fishy and the Black boxes should have been opened in ffice:smarttags" />lace>Polandlace> not lace>Russialace> we all know they will manipulate them if there is any indication that they will be blamed. fficeffice" />>>


                              Poland presses Russia to pass on Smolensk crash black boxes


                              20.04.2010 14:26

                              Polish military prosecutors have asked Russian investigators to let them have access to recordings from two black boxes, including the pilots conversations in the lead up to the disaster.


                              Two Tu-154 flight recorders, which contain flight parameters and voice recordings are being examined at the laboratory in Moscow by Russian investigators and Col. Zbigniew Rzepa from the Polish Supreme Military Prosecutor’s Office.

                              The Polish prosecutor reveals that the voice recorder contains the last thirty minutes of the flight, including pilots’ dramatic conversation and horrific screams on the flight deck moments before the Tupolev-154 hit the ground.

                              The recording has not yet been fully decoded. At the moment Russian investigators are trying to identify voices recorded on the black box. If they do not manage to match voices with the flight crew, they will ask Poles, probably the pilots’ colleagues, for help.

                              It has not been established yet whether any of the passengers contacted the crew during the last moments of the flight.

                              “This is not clear because identification of voices is very difficult and takes time,” said Rzepa.

                              Today, Prosecutor General Andrzej Seremet will reveal details concerning the investigation on the cause of the presidential plane’s crash, based on inspection of the crash site and plane’s wreck, victim’s postmortem and witnesses’ testimonies. (mg)

                              Source: Gazeta Wyborcza

                              Comment


                              • Originally posted by dash88 View Post
                                How many trees do I need to hit before realizing ' hmm maybe I'm too low!!' what a meathead pilot...sorry for the term but in this case u just have to be..
                                You on the other hand are a genius Sir after arriving at this conclusion based on the 2D birdseye view. They started climbing after the first tree, the problem was that the rising terrain outclimbed them.

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