Crashes in the News - Thread

Discussion in 'Rules and Regulations / Flight Safety / Better Pil' started by choppergirl, Jun 8, 2016.

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  1. Mar 15, 2019 #1941

    Turd Ferguson

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    I think it's not. There's no mechanism in place for that to happen. As far as I know, that's not even in the "maybe in the next 20 yrs" forecast
     
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  2. Mar 15, 2019 #1942

    Topaz

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    Yeah, I really think they're not. Because they're not. It's a dream, but not a reality yet.
     
  3. Mar 15, 2019 #1943

    BBerson

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    I think AirFrance base was getting some telemetry for maintenance on that Airbus that crashed in the Atlantic.
     
  4. Mar 15, 2019 #1944

    Turd Ferguson

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    Our aircraft can transmit a snapshot of data through the aircraft's ACARS but it's on VHF and limited to line-of-sight. I think maybe that can use satellite as well. Also very limited on how much data can be in one data pak (burst) transmitted by ACARS so not sure how they decide what to monitor. The joke is they are making sure we don't have the thrust firewalled, which is silly because we only do that on the last leg.
     
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  5. Mar 15, 2019 #1945

    BBerson

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    I heard this morning the trim jack screw was found in the nose down position.
     
  6. Mar 15, 2019 #1946

    BJC

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    I heard that the trim system is easily disconnected. I also heard that the manual trim wheel can easily be stopped simply by the co-pilot’s grabbing it or the pilot’s grabbing the co-pilot’s leg and pulling it against the wheel.


    BJC
     
  7. Mar 15, 2019 #1947

    Vigilant1

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    Yes, this is apparently the bit of material from the crash site that the FAA was referring to yesterday. It is consistent with H-stab/trim/MCAS issues that are believed responsible for the Lion Air crash. IMO, it doesn't mean the planes are unsafe to fly, and I'd board one today operated by a US carrier without any hesitation (after all, the situation and fixes are, as far as we know, identical with what we knew after the Lion Air crash. The planes can still be flown safely if the crew takes appropriate action). I guess the thinking is:
    1) They'll be safer after Boeing makes a software fix (reportedly input from multiple AoA sources plus other changes)
    2) Authorities knew about the issue in the aftermath of the Lon Air crash, bulletins were issued, crews made aware of the existence of the MCAS, and apparently it's not sufficient as evidenced by this crash.

    Bad news for Boeing.
    As buggy/finicky as airliners used to be, I guess we just couldn't fly those planes today. Fuel management of the DC-8, etc. Lots of emphasis on crew training and discipline. And they did have another person on the flight deck. And everybody in the front knew how the plane worked. Well there's no doubt that it is safer to fly now than it used to be.
     
    Last edited: Mar 15, 2019
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  8. Mar 15, 2019 #1948

    bmcj

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    Is 250 knots also the rule in he country where this happened?
     
  9. Mar 15, 2019 #1949

    plncraze

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    I thought airliners could avoid the 250 knot rule in certain places to keep traffic flow up in the big airports.
     
  10. Mar 15, 2019 #1950

    BBerson

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    The airline said the pilots received the recent training. (maybe Boeing should double check these pilots, as I said after the previous Max crash) https://www.washingtonpost.com/worl...ory.html?noredirect=on&utm_term=.f464996647bc
     
  11. Mar 15, 2019 #1951

    PiperCruisin

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    Question...sorry if it has been asked, did not see it...

    Why was this system installed in the first place? I hear some media reporting that because the engines were larger, produced more thrust, and moved higher, it created some stability/thrust issues where they felt it necessary to add the MCAS "feature". I don't buy it. My guess is that some arm chair quarterback in the C-suite decided it was needed because of the AF447 accident despite Airbus being FBW with side sticks and Boeing with yolks. Then someone decides to keep it real simple so they do not have to do as much software validation rather than cross checking multiple sensors before putting the plane into a dive. Maybe I am just being cynical...it's ok you can say so.
     
  12. Mar 15, 2019 #1952

    davidb

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    Interesting, but that alone isn’t conclusive of a runaway trim (MCAS) problem. An erroneous airspeed indication (improperly handled) could have led the crew to fly incredibly fast, say the 380 knots that was indicated in the ADS-B data. At that speed one would expect a rather nose down trim position to achieve a “trimmed for that speed” condition. Also, the plane would be very pitch sensitive at such a speed. Red line is 340.
     
  13. Mar 15, 2019 #1953

    Topaz

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    My understanding (unconfirmed, from another part of the Internet) is that the airlines wanted the MAX 8 to use the same training syllabus as the rest of their 737 fleets, as a cost-saving measure. The larger engines (fans) on the MAX 8 (and MAX 9) cause a mild pitch up in some high-alpha scenarios, which would require model-specific training that the airlines didn't want. Boeing wants to do whatever their paying customer wants. The FAA apparently told the airlines (and Boeing) that, if they wanted to use the same training, the airplane needed a system to mitigate the pitch-up so that pilot response was no different than other 737's the pitch-up issue was invisible to the pilots. Boeing created MCAS as a response. "Everyone is happy." The only training change was to know to turn off the MCAS with a switch, rather than by manually moving the yoke, like the autopilot. This was, in 20/20 hindsight, not given enough visibility in the training materials, and so we have the Emergency AD on the POH/training materials as a result of the Lion Air crash, where that particular airplane had issues that resulted in MCAS and the crew fighting each other. The other crews had apparently read the new POH, but the crash-flight crew didn't turn off MCAS even after they'd been trying to fight it.

    Whether or not this has anything to do with the Ethiopian crash, where the crews are supposedly much better trained than those of Lion Air, I don't know, and neither (yet) does anyone else.
     
  14. Mar 15, 2019 #1954

    BBerson

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    Yeah, why install a system that nose dives it into the ground if the pilot doesn't disable it first?
    Why can't it just bring the nose down just enough to avoid stalling and stop?
     
  15. Mar 15, 2019 #1955

    Vigilant1

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    The sensor for the MCAS, as I understand it, is one AoA sensors. If that sensor is faulty, the MCAS does think it is just getting down to a safe AoA.
    If the crew just turns it off (turn off "electric trim", same as you do in a runaway trim situation) and manually trims with the wheel, everything is fine.
     
  16. Mar 15, 2019 #1956

    BBerson

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    One bad sensor should not result in a crash or a need for pilot intervention.
     
  17. Mar 15, 2019 #1957

    radfordc

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    Let's not say cynical...more like ignorant. Of the facts that is.
     
  18. Mar 15, 2019 #1958

    Vigilant1

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    If the "answer" is some sort of software "voting" between the two AoA vanes, maybe some AI that uses the apparent pitch, power and airspeed to suss out the truth and then act (ala Airbus), I'd much much rather stick with what is there now, and add a warning when the AoA vanes disagree. Make things obvious so a trained crew can fly the plane.
     
  19. Mar 15, 2019 #1959

    rv6ejguy

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    Nearly 400 knots 3 minutes into the flight, barely having the high lift devices stowed seems unusual.

    Will be interesting to find out how these 2 pilots were trained/tested on the system and by whom. Hopefully it was more than a briefing and involved some Sim time with the MCAS disabled, hand flying. Hard to know what to expect from a briefing but scaring yourself or crashing the SIM will stay with you for a while and simulation makes you go through the actual procedures and control feel in the cockpit. I'd hope after the Lion Air crash, everybody including Boeing, devoted more Sim time to dealing with MCAS failures. If something doesn't feel right, they better know how to disable it fully and quickly and hand fly the thing. Seconds count here. I'd have to think that a pilot like Sully would have got the plane back on the ground in one piece if it was just a MCAS anomaly.

    Looking at the terrain data around the airport and the direction of flight, most of where they were heading was at 8000 to 8400 MSL- only a few hundred feet higher than airport elevation. http://en-gb.topographic-map.com/places/Addis-Ababa-8976505/

    They were not heading towards the 10,000 foot mountains to the north.

    Most of these types of incidents happen at night but this would appear to be day time, and the weather was clear. Lots of visual cues that something is very wrong if you can see the ground. Air France 447, Aero Peru 603 had to decipher what was going on from erroneous instrument readings. Seems like a backup GPS altitude and GS display could save a lot of confusion when primary instruments are not making sense.
     
    Last edited: Mar 15, 2019
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  20. Mar 15, 2019 #1960

    henryk

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    Last edited: Mar 15, 2019

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