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Aeroplanes

Discussion in 'Engineering' started by amusicsite, 11 Mar 2019.

  1. amusicsite

    amusicsite dn ʎɐʍ sᴉɥ┴ Staff Member

    Location:
    UK
    https://phys.org/news/2019-03-grounding-boeing-touchy-subject-authorities.html

    Looks like Boeing has a major problem on their hands with their 737 MAX 8 aeroplanes.

    They have a full order book and are a major employer in the USA. As well as their planes being a big trading chip in their ongoing trade fight white China.

    I think this will be one of the fastest investigations ever seen. It has to be. If they loose another one of these planes it could destroy the company, ground hundreds of planes around the world and really hurt the American economy.
     
  2. amusicsite

    amusicsite dn ʎɐʍ sᴉɥ┴ Staff Member

    Location:
    UK
    https://phys.org/news/2019-03-boeing-airlines-tough-path-max.html

    Well as the pressure builds and customers don't want to fly on these planes, Boeing has grounded it's entire fleet. While not a large percentage on the entire global fleet are made up by these aeroplanes, there is also not that much slack in the industry. So it's very disruptive to some airlines hand looks like Boeing will have to pick up the bill of they want to keep airlines happy.

    How long this takes to fix and if the fix works could determine if they stay in business.
     
  3. amusicsite

    amusicsite dn ʎɐʍ sᴉɥ┴ Staff Member

    Location:
    UK
  4. amusicsite

    amusicsite dn ʎɐʍ sᴉɥ┴ Staff Member

    Location:
    UK
    Well I think we have learnt a few lessons from these disasters so far.

    1) https://arstechnica.com/information...-have-prevented-737-max-crashes-as-an-option/

    It seems criminal to me that you would sell a safety feature as an add-on. Surely you would want all your planes to be as safe as possible. Indeed Boeing might be thinking the same as they seems to have lost the confidence of many airlines, who even if they have the add-on and it's safer probably don't want the hassle of trying to explain to their customers why their versions are safer.

    2) https://uk.reuters.com/article/uk-e...some-max-737-orders-in-jeopardy-idUKKCN1R30L9

    Don't let things like planes be self certified and probably not a good idea to let them give government's backhanders lobby the government either.

    3) Part of the problem seems to be caused by sensor failure. If you have automation then your sensors are king! Make sure they work, make sure you have enough built in redundancy and certainly don't charge extra to see if there is a problem (see No.1).

    4) Semi-automation can work but it can have problems. If something is automating a process then the pilot should be very aware of what it's doing and probably a good idea to allow the pilot to fully override it in case of an emergency, or at least be able to inform the automated system it's doing something wrong.

    Hopefully we will learn from this and other lessons which will make suture planes safer. As to whether Boeing can survive this and be one of them plane makers is yet to be seen. I've already heard of one airline wanting to drop an order for 50 planes, something like a $5 billion contract and looks like they will be taking their money to AirBus.
     
  5. amusicsite

    amusicsite dn ʎɐʍ sᴉɥ┴ Staff Member

    Location:
    UK
  6. amusicsite

    amusicsite dn ʎɐʍ sᴉɥ┴ Staff Member

    Location:
    UK
    https://phys.org/news/2019-04-ethiopian-faulty-sensor-jet.html

    Not many surprises in the first official report form the Ethiopian airline crash report. The pilots followed the right procedures. They repeatedly turned off the anti stall but it kept reengaging. The initial problem was faulty data from the wind speed sensor. They say that both Boeing and the FAA are at fault for allowing these planes to fly with such a poorly thought out system.

    There are a few things I don't get though. Firstly Boeing seem to think they can fix this with a software update but I'm not so sure. It does not fix the problem of why the sensors on relatively new planes keep falling or the problem of there only being two of these sensors, so if one gives bad data you have no idea which one it is.

    The other thing is why do they even have the anti stall system in place. It's not like we have had a string of planes this size falling from the sky because they have stalled. I've not heard anyone talk about a case where this system would have prevented an accident. The pilots that fly commercial jets that hold a hundred or more people are well trained, they have 2-3 people in the cockpit and should be able to spot a potential stall condition well before it goes critical. The only reason I can see for adding it would be so you could allow less qualified or less people be in charge of flying a plane like this.

    I guess it's Boeing's route to taking their aeroplanes down the fully autonomous route but I think doing that incrementally seems a folly. Especially with a poorly implemented solution like this. Ultimately though I think it will help aeroplanes on the journey to full autonomy. It has taught the industry a valuable lesson. When taking control away from humans then your sensors become the most critical thing on the plane. Which is the same for pilots. They have to have regular eye tests and lots of rules like no drugs and no hangovers to ensure they keep their licence. Likewise the sensors on planes need to have a good working life span, regular testing and a lot of built in redundancy.
     
  7. amusicsite

    amusicsite dn ʎɐʍ sᴉɥ┴ Staff Member

    Location:
    UK

    View: https://youtu.be/H2tuKiiznsY


    This is a really good explanation as to what the problem they were trying to fix is and why it was needed. It's mainly because they moved the engine up and that can cause it to get into a stall condition when climbing. I guess the solution needs to find the right balance between stopping the potential increased risk of stalling and not smashing the plane into the ground.

    As they seem to be close to saying they have a working solution, only time will tell if they have that balance right.