Announcement

Collapse
No announcement yet.

Aeroflot Superjet 100 fire and evacuation at UUEE

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

  • Evan
    replied
    Originally posted by 3WE View Post
    And glad to know that stupid pilot screw ups and bad training are still where your emphasis lies.
    Here we are again. By correcting the assumptions and myths of FBW with the FACTS, I am instantly blaming the pilots.

    My emphasis lies with cutting through the BS.

    Leave a comment:


  • 3WE
    replied
    Originally posted by Evan View Post
    [...a bunch of stuff including a Wiki quote that FBW often helps with stability and that I shouldn't rush to conclusions (I believe my words were I am curious as to what the final report is regarding this stuff...I don't think I rendered any conclusions...not that words don't matter or anything.)]
    You and LHB having a few?

    Indeed, it is almost Beer:30 in Flyover, America?

    And glad to know that stupid pilot screw ups and bad training are still where your emphasis lies.

    Leave a comment:


  • Evan
    replied
    Originally posted by 3WE View Post
    Sorry that I am always parroting negative myths about HAL, but I think he often helps out with stability in all three axes...maybe even a slight emphasis on pitch & phugoids and all...
    Right, because HAL is an autonomous sentient-being with artificial intelligence who presides over all FBW aircraft in exactly the same way and can make random things happen for no reason.

    The SSJ FCC's on the other hand, have nothing to do with artificial intelligence and do not follow the same sentient-being behaviors of other FBW aircraft laws.

    So, for example, unlike the A320/330/340, the SSJ control law retains full damping functions in direct law. Read carefully:

    Originally posted by Alexander Dolotovsky, Deputy Chief Constructor for Aerodynamics, SCAC
    Minimum mode, when all PFCU, air-data or inertial-reference input is lost, is close to Airbus's "direct law", but with improved manual handling qualities as the damping is still available in roll, yaw and pitch channels. "There is no envelope protection, but handling qualities are close to normal," says Dolotovsky. He adds that the improved handling in minimum mode was well received by SSJ launch customer Aeroflot, which says that the aircraft's control laws are more acceptable compared with Airbus FBW, which lacks Dutch roll damping in direct law.
    Originally posted by Alexander Dolotovsky, Deputy Chief Constructor for Aerodynamics, SCAC
    [The control laws written for the original yoke version of the SSJ] are now in the minimum, backup mode. Thanks to these algorithms and the good stability of the aircraft, in the źDIRECT MODE╗ RRJ reminds our old good Tu-134. I won't tell you a secret if I say that we easily lifted the plane in the air and flew more than three months of test flights (if we count the whole program) using the Direct mode. By the way, some of our pilots like źDIRECT MODE╗ even more than the źNORMAL╗, because in the Direct mode the plane does not restrict a pilot and control characteristics differ little. This is also a great achievement, because , for instance, entering the źDIRECT MODE╗ during the education on A320 is only performed on a simulator and during the flight, while we can perform the whole flight in the źDIRECT MODE╗ and mid-level trained pilots can still control the plane.
    In fact, this is an entirely Russian HAL:

    All software that controls the electronics is actually created by us. We have developed the complete logic of control laws. This intellectual property was created while we were developing our plane.
    It is also robust:

    In order to "knock out" such a system, it is necessary to destroy more than 70% of computers, which is almost impossible given their heterogeneous hardware and software.
    But the apocryphal myths will continue as long as Stanley Kubrick fans who can't tell their ass from a pocket calculator have anything to say about it.

    Originally posted by Wikipedia, Aeroflot Flight 1492 / citing Bjorn Fehrm, Leeham News and Analysis
    The bounced landing could be a consequence of the aircraft fly by wire controls reverting to direct mode after the lighting strike, being less damped and more sensitive.
    Hey, who needs research when you're already an expert...

    --------------------------

    Now, I concede that the direct law handling will be somewhat different from the normal law one, so if a crew had no experience flying in direct law, perhaps it played a role. I wouldn't rush to that conclusion however and I think it takes more than some minor handling differences to bounce a plane like that.

    Leave a comment:


  • 3WE
    replied
    Originally posted by Evan View Post
    Taking the FCC's out of the loop shouldn't result in an uncontrollable aircraft. Unless you don't know how to fly it that way...
    Basically concur EXCEPT they didn't reach up and flip off an FCC switch. A big jolt of lightning did it for them along with who knows what else- the flat-screen TVs? the flaps? Not sure if the training covered exactly that. And if your DC-10 suddenly becomes an MD-11...sometimes folks mess that up in spite of good intentions and training...

    Edit/Acknowledgement- As you say, there's indications that flaps were set. There's also comments that they were going very fast. Was the Airspeed indicator fried (or black?) and they were carrying extra speed because of all the parlour talkers bad mouthing the French pull up experts? Anyway- I can imagine why they might have been fast...and one reason is that they were crappy pilots...fried electronics is another. For now, I give a little more credence to the latter...and you?

    Edit #2:
    ***apocryphal HAL myths***
    Sorry that I am always parroting negative myths about HAL, but I think he often helps out with stability in all three axes...maybe even a slight emphasis on pitch & phugoids and all...

    Leave a comment:


  • Evan
    replied
    Originally posted by 3WE View Post
    In the meantime, I await the final report where flap operation, spoiler operation, and pitch stability while in a lightning-affected state will hopefully be detailed.
    Flaps are deployed in the post-accident photos.

    Instead of parroting the apocryphal HAL myths of the interwebs, I would focus on how and why a common lightning strike penetrated and damaged the electrical system and avionics (perhaps it was uncommon lightning).
    Taking the FCC's out of the loop shouldn't result in an uncontrollable aircraft. Unless you don't know how to fly it that way...

    Leave a comment:


  • 3WE
    replied
    Originally posted by Evan View Post
    Listen to yourself.

    I've heard it said that if you have basic pitch control and thrust control you can slow down...
    Nice try. Thanks for playing...

    #1. The guys are said to have landed fast. I don't know why, but maybe there's these electrically controlled flap thingies that are essential for slowing down enough to land nicely- but maybe the flap control system got fried by the lightning bolt?

    #2. Using genius fundamental airmanship to not stall the shit out of an alternate-law, largely-healthy airliner at 36,000 feet versus managing a crippled airliner 3 feet off the ground when alternate law is possibly porpoiseeee...not really apples to apples.

    I am glad to know you would not porpoise the 100 Superjet- but I ask if you actually have enough hours- including flying it after a lightning strike- to make that claim.

    However, in my experience, I've had some lateral PIO's on my bicycle and Toyota Corolla and some pitch PIPorpoiseOs on my instructor's 172...

    ...those three things give me a little sympathy for the MD-11 guys and maybe these guys.

    In the meantime, I await the final report where flap operation, spoiler operation, and pitch stability while in a lightning-affected state will hopefully be detailed.

    Leave a comment:


  • Evan
    replied
    Originally posted by 3WE View Post
    but you fry HAL and it becomes nasty...

    ...and then you have a fried airplane that for some reason you can't slow down...
    Listen to yourself.

    You fry HAL, you get FBW without HAL. You fry the FBW, then you don't bounce on the runway, you go straight into a potato field. Obviously, the FBW was still working (although maybe off the RAT or the batteries).
    I've heard it said that if you have basic pitch control and thrust control, you can slow down. Or you can go around.

    Leave a comment:


  • 3WE
    replied
    Originally posted by Evan View Post
    ***no disrespect to your avgeek discussion on PIO vs porpoising technique—the best way to avoid getting bouncy is to keep it stabilized or go around.***
    Indeed.

    BUT...

    Maybe the normal airplane isn't bouncy, but you fry HAL and it becomes nasty...

    ...and then you have a fried airplane that for some reason you can't slow down, and rules that it's generally a little bit bad to go around AFTER touchdown...

    ...and a fried airplane that you really WANT to get on the ground...

    It's a sad combination- and if you want to write procedures for it, fine...but I'm also thinking this is another crew where HAL abandons them AND throws them who knows how many red blinking and beeping lights.

    No disrespect intended in the youtube- the humor below is based on some truth of blinking-light-overload.

    https://www.youtube.com/watch?v=M1WemnsB98o

    Leave a comment:


  • Evan
    replied
    Originally posted by 3WE View Post
    Ok...Boeing is ancient, napping and sucks.

    The Russians are large, and in-charge and modern.

    But is there some possibility we are discussing a design flaw?
    Yes! (I would almost say 'obviously')

    Do Boeings go into alternate law and bounce down runways when struck by lightning?
    The irony. First, there were the legions of posts demanding a 'give me the plane' switch (i.e. direct law). Now there is 'how can we expect to fly this thing in direct law?'.

    Direct law: stick commands are directly proportionate to control surface movements.

    As I said above, SSJ pilots have reported that the handling is very benign (even improved) in the SSJ version of direct law. So, assuming no other malfunctions, that alone should not inhibit control.

    I've also heard it said that if you are stable down to the flare, you aren't going to get bouncy and if you are unstable before the flare, you go around and do it again.

    So I think—no disrespect to your avgeek discussion on PIO vs porpoising technique—the best way to avoid getting bouncy is to keep it stabilized or go around.

    However, many questions remain unanswered on this one, including what exactly failed and what didn't, so who knows what the pilots were up against and if it was even possible to control a stable approach.

    Leave a comment:


  • BoeingBobby
    replied
    Originally posted by Black Ram View Post
    Well that's not a very fair comparison. Sure, even the most modern Soviet airliners before the Cold War ended - the TU-154M and the IL-86 - had your favorite steam gauge cockpits and required at least 3 pilots, which made them look obsolete compared to the latest western planes in service - 757, 767, A300, etc. But if you look at later Russian planes, like the TU-204 and the IL-96, they have modern cockpits and FBW. And still they are behind, but that's besides the point.
    Crew of 3! The AN-124 has a crew of 11!

    Leave a comment:


  • 3WE
    replied
    Ok...Boeing is ancient, napping and sucks.

    The Russians are large, and in-charge and modern.

    But is there some possibility we are discussing a design flaw?

    Sure, the SuperJet doesn't have DCAS.

    BUT

    Do Boeings go into alternate law and bounce down runways when struck by lightning?

    I'm sure that engineering teams at both places tried really hard.

    Leave a comment:


  • Evan
    replied
    Originally posted by Black Ram View Post
    OK, the aspect ratio of the wing. Russians are actually pretty good at aero research. But a modern airplane is not just the wing design.

    This is an airplane that entered service in 2011. Where are the cheap composites? No wingtip devices or raked wing - only in 2017 they came up with the saberlet concept.
    Also, from wikipedia - special mods and control law settings had to be adopted for the steep London City Airport approach. And in 2018, that super efficient wing was looked into again and they found they can improve it by 10%.

    The engines are really outdated. I haven't heard of a new PW1000G version being planned. That would be a big surprise to me. Even the MS-21 might have some trouble getting the PW1000G for political reasons.
    They need western components, and it doesn't seem like they can make CFRP components without foreign help. All that costs money, and might be subject to sanctions. I don't think they can build a plane as efficient and capable as the 737 MAX at the fraction of the price.
    The NG of the SSJ is planned (really no idea what the status of the SSJ-130 is at this point) to use all-new wings derived from the MS-21 development and the PW1000G. If it comes together, it should be a serious contender. It is possible because the SSJ is a relatively modern airframe with which to build on. Unlike the 737.

    The MS-21 features CFRP wings and is powered by the PW1400G. It's already flying. Surprise! The Russians have been busy. Boeing has been napping and has fallen well-behind. Real tortoise and hare stuff.

    Click image for larger version

Name:	MS-21_cockpit.jpg
Views:	1
Size:	617.6 KB
ID:	1034977

    Not your papochka's Tupolev...

    Leave a comment:


  • Black Ram
    replied
    Originally posted by Evan View Post
    but to call it sub-par is a disservice to the people who designed it and all the hard work that went into it.
    Since I used that phrase - I was talking about the dispatch reliability and the time the planes spend flying and not stuck on the ground, which are dismal.


    Originally posted by Evan View Post
    In other words, Boeing needs to brush off the arrogance, get its head out of its ass and come up with a 21st-century design of their own. Before the Russian's invade.
    I agree on Boeing, but the Russians won't invade for quite some time. They don't really have the technology. They need western components, and it doesn't seem like they can make CFRP components without foreign help. All that costs money, and might be subject to sanctions. I don't think they can build a plane as efficient and capable as the 737 MAX at the fraction of the price. Unless they sold the plane at a huge financial loss, hoping to get orders and ramp up production quickly.

    Leave a comment:


  • Black Ram
    replied
    Originally posted by BoeingBobby View Post
    Have you ever been up close to a Russian aircraft? I have to many, as long as the crew promised not to start it I was happy to take a look. The AN-124 and the IL-176 look like they have instruments from a WWII submarine in them. The smell is usually the same as the porta-pottys at the fairgrounds. Our company was not allowed to have crew travel on any Russian aircraft or airline.
    Well that's not a very fair comparison. Sure, even the most modern Soviet airliners before the Cold War ended - the TU-154M and the IL-86 - had your favorite steam gauge cockpits and required at least 3 pilots, which made them look obsolete compared to the latest western planes in service - 757, 767, A300, etc. But if you look at later Russian planes, like the TU-204 and the IL-96, they have modern cockpits and FBW. And still they are behind, but that's besides the point.

    Leave a comment:


  • Black Ram
    replied
    Originally posted by Evan View Post
    Do a bit of research. There's a lot of high-tech development that went into the SSJ, particularly the 9.9 aspect ratio wings. The FBW is state-of-the-art and very robust, (using LLI (Liebherr Lindenberg) FCC's and Thales avionics, some purpose built from scratch). It is certified as a Protected Aircraft. It is also modern is its reduced complexity.

    "Ultra-modern", maybe not, but definitely a modern, 21st century aircraft. Much more modern than the 737-Max. There may be some serious design issues that come to light as a result of the investigation, but otherwise, it's a pretty impressive aircraft for a first-time effort.

    OK, the aspect ratio of the wing. Russians are actually pretty good at aero research. But a modern airplane is not just the wing design.

    This is an airplane that entered service in 2011. Where are the cheap composites? No wingtip devices or raked wing - only in 2017 they came up with the saberlet concept.
    Also, from wikipedia - special mods and control law settings had to be adopted for the steep London City Airport approach. And in 2018, that super efficient wing was looked into again and they found they can improve it by 10%.

    The engines are really outdated. I haven't heard of a new PW1000G version being planned. That would be a big surprise to me. Even the MC-21 might have some trouble getting the PW1000G for political reasons.

    Sure, the SSJ has FBW. But even the TU-204 had that.

    From what I've read in articles and on forums, the planes are spending more time on the ground than flying and everyone is looking for a way out - except for Peruvian, which is showing interest in acquiring them.

    Leave a comment:

Working...
X