• t0mas88 2 days ago

    Note that despite what media headlines will make of this, it wasn't a Boeing issue in this case. One of their suppliers incorrectly installed a bearing on a component that could lead to moisture getting in and freezing. That component is used on the 737NG and 737Max.

    These things are relatively common in aviation. An incident happened, everything went OK, but during the investigation a problem was found. The NTSB then writes a set of recommendations and it's likely that the FAA will issue an Airworthiness Directive (AD) that tells all operators to fix this problem.

    Depending on the severity and the FAA's estimate of the risk that AD will either be a "fix now" which is very disruptive or a "fix at the next [some type] inspection" which is more common.

    Specifically with this component the NTSB seems to think it can be removed until a replacement is available:

    > Additionally, the NTSB recommended that the FAA determine if actuators with incorrectly assembled bearings should be removed from airplanes, and if so, to direct U.S. operators to do so until replacements are available.

    In that case the plane won't be able to do a cat III autoland anymore, but from the text is looks like it would operate normally apart from that restriction.

    • tialaramex 2 days ago

      Category III autoland (other than to "keep your hand in") is relatively rare anyway because it solves only a specific narrow problem.

      Suppose there is one plane and it needs to land right now, but all nearby airfields are fog bound so a human couldn't land a plane there: they'd get to minimums, still not be able to see the field and abort every time until they divert to somewhere with better weather - the Cat III autoland doesn't need to see the field, it will land anyway. You have to absolutely trust the machine, this is a rare Fail Active system - humans can't necessarily help even if things go wrong so once it reaches minimums it must land the plane even if it later ceases to have 100% confidence that it can do so correctly due to systems failure.

      But now we're done, the plane is on the ground, on a runway, the passengers are no longer in the sky, if the plane was about to explode or run out of fuel that's awesome, but we can't do this again, autoland doesn't taxi the plane, and it can be pea soup out there, the pilots still can't see the ground even though they know their plane is firmly landed.

      So if there's a stack of fifty planes for JFK and it's zero visibility this technology lands one plane per runway, maybe you can land three or four, then it's effectively closed, that's 46 planes left to divert, it's not useless, especially when visibility is marginal rather than truly zero, but it does not allow the airports to stay running normally.

      • t0mas88 2 days ago

        Agree that autolands are rare, but they are used for low visibility procedures and it's not "1 plane per runway". Almost the opposite, typically you would only use a limited set of runways in such conditions and severely limit the complexity of ground routing.

        Practically real zero-visibility almost doesn't happen. There will be some visibility just very very little.

        You can taxi slowly (think 10 miles per hour) following bright centerline lights in quite low visibility. But it would be very dangerous to manually control a landing rollout at 150+ miles per hour in that visibility.

        • ExoticPearTree 2 days ago

          I think you got the last part wrong. Airplanes have GPS and they know where they are on the runway, where the taxiways are and so on for all the airports they operate in.

          Just as they can take off in low visibility, they can also maneuver. And airports have ground radars that know where every plane on the ground is, even if the ground controllers are able to see the planes with their own eyes.

          Otherwise, in a lot of places airplanes wouldn't land pretty often :)

          • raverbashing 2 days ago

            > the pilots still can't see the ground even though they know their plane is firmly landed.

            They get a "Follow me" car to help the plane taxi out

            Slower, but it is not like the plane will stay on the runway

            • tialaramex 2 days ago

              For a "Follow me" car to work, you still need good enough visibility to see the car's lights. Is that always true? I'd guess that in the worst snow storms it's already not true as far South as JFK.

              • t0mas88 2 days ago

                Low visibility due to fog happens regularly in places like Amsterdam and London. You can see taxiway centerline lights or a follow-me car in that, but you can't manually land in it.

                Below 300m / 1000ft visibility you're down to autoland cat III while you can taxi in that with no problems.

                • tialaramex 2 days ago

                  How often do you think they actually do Cat III out of necessity, at say Heathrow or Schiphol ? My guess would be that having Cat III capability makes them comfortable - because they can land planes anyway if they need to, but it isn't often (maybe 2-3 days per year) actually used "in anger" so to speak. Cat I and II autolandings are common, because they mitigate visibility problems while leaving the final decision to a human pilot, but the pilots don't like Cat III precisely because they get this job to fly and in Cat III you're not flying the plane.

                  And yes, as I noted, when visibility is marginal you could continue normal operations with Cat III at a reduced pace and Heathrow has been known to do that, but it's extremely disruptive. The problem is that as visibility reduces our options continue to narrow further. At just Cat IIIa where as you say the pilots can just see the signs and drive down a taxiway without problems, Heathrows targets 50% capacity, and as things worsen that falls, to 10% and eventually the airport is closed to normal traffic. Why low capacity at just Cat IIIa? Because of radio protection, the aeroplane is made of metal, so you need to reduce pace so that there's no risk of interference from the plane ahead of you during your autoland approach. If you were visual, even in Cat II, you'd be fine because you can see if there's a problem and abort, but in Cat IIIa you're absolutely reliant on radio beacons so there cannot be any problems.

            • CPLX 2 days ago

              This is not at all an accurate description of the typical applications of the CATIII landing procedure in practice.

            • aflukasz 2 days ago

              > Note that despite what media headlines will make of this, it wasn't a Boeing issue in this case. One of their suppliers incorrectly installed a bearing on a component that could lead to moisture getting in and freezing. That component is used on the 737NG and 737Max.

              Seems like a Boeing issue to me.

              • diggan 2 days ago

                Parent sounds a bit like the software engineers who blame random FOSS libraries for the bugs that appear in their own projects using said FOSS libraries.

                In your project, you're ultimately responsible for what you ship, even if you're shipping airplanes.

                • t0mas88 2 days ago

                  Technically yes, Boeing is responsible for the whole plane, but that's not what I meant. What I meant was that the media will make this an "OMG Boeing very bad!" story while it's quite routine for these things to happen.

                  And in aviation components it's also a lot more nuanced than some developer blaming a FOSS component without warranty. A supplier of certified aviation components (like Collins in this case) also has a responsibility to deliver components that meet their certification standards. The FAA will go after them directly, not Boeing, if what they ship doesn't pass the certification standards it's sold as having.

                  • diggan 2 days ago

                    > it's quite routine for these things to happen.

                    NTSB routinely issues "Urgent Safety Recommendations"? According to the table at https://www.ntsb.gov/investigations/Pages/safety-recommendat..., there wasn't any in 2023 at all, so doesn't sound very common, but maybe things have changed since then.

                    • Dalewyn 2 days ago

                      I despise "OMGWTFBBQBOEINGBAD" sensationalist clickbait just as much if not more than you, it's an exemplary example of why journalism is a cancer upon humanity.

                      But just like a broken clock is right twice a day, the sensationalism is right here. It's a Boeing problem. Worse, the 737 had (unrelated to this) rudder problems in the past that led to crashes.

                      So: Yeah, fuck Boeing. I can't wait for them to go bankrupt so we can all go in and restructure the fucking thing from the ground up.

                  • madaxe_again 2 days ago

                    Indeed. If I am putting together a product and I rely on an assembly from a third party, it’s my responsibility to ensure that I have adequate QC processes in place to ensure that assemblies are made to spec before accepting them. To simply take a supplier’s word for it is negligent.

                    • sonotathrowaway 2 days ago

                      A long time ago I was in auto sales. I had a customer who worked at a factory that produced parts for many brands of automobile.

                      That customer would only buy a Honda car, because they said they observed how absolutely strict Honda was regarding the quality of parts that they would purchase.

                      Their quality control process for a random part was so meticulous that it gave them faith in the brand as a whole.

                      • madaxe_again a day ago

                        I had a similar experience with BAE. The first time I saw they were charging the RAF £5,000 for a torch lightbulb my eyes practically fell out of their sockets - but then, a few years down the road, I found myself working with a QC department there, and their acceptance testing is extraordinary - everything gets the crap beaten out of it, thermal, endurance, vibration, radiation, you name it - and the survivors become aircraft and weapon parts.

                  • holsta 2 days ago

                    > [..] it wasn't a Boeing issue in this case. One of their suppliers [..]

                    The world would look very different if organisations were on the hook for the actions of their suppliers.

                    • iudqnolq 2 days ago

                      The door plug could also be spun as a supplier issues. Ultimately this points to poor supplier management at Boeing. Boeing realizes this, and is taking steps to address it including purchasing Spirit.

                      • bcrl 2 days ago

                        Did you read the whistle blower commentary on internal notes on the plane that had the door plug blowout? It wasn't a supplier issue: the people inside the factory had an off-the-books message board that directly discussed what happened on that plane, and it was precisely because the Boeing employees that removed the door failed to record the door removal in the official logs that the failure to properly reattach the bolts was not detected. Door removal is one of the activities that would have required a reinspection. It was Boeing's fault through and through.

                      • mystified5016 2 days ago

                        > it wasn't a Boeing issue in this case. One of their supplier

                        Isn't farming things out to unreliable suppliers the core problem with Boeing? All of their problems boil down to "we have the lowest bidder manufacture everything"

                        That is very much a Boeing problem. They're responsible for choosing qualified vendors and verifying the quality of their work because literally everything puts hundreds of innocent lives on the line.

                        • sonotathrowaway 2 days ago

                          Step 1: spin out all your suppliers into their own companies

                          Step 2: use pricing power to force your suppliers to cut corners in order to survive.

                          Step 3: claim plausible deniability for the scores of suppliers giving you substandard parts. Roll in your money while telling the rest of the world you couldn’t have done anything differently.

                          • howard941 2 days ago

                            It's worse than this. According to TFA the actuator is mechanically attached even during non-precision approaches.

                            • inferiorhuman 2 days ago

                                In that case the plane won't be able to do a cat III autoland anymore
                              
                              The actuator is only used for Cat 3b autolandings, which United doesn't do anyways.
                            • underseacables 2 days ago

                              I am not a pilot, but is it possible we are inching towards a scrapping of the Max? The reliability of the plane seems to be in ever increasingly doubt

                              • XlA5vEKsMISoIln 2 days ago

                                    body { overflow: unset; opacity: unset !important; }
                                • blackeyeblitzar 2 days ago

                                  I read elsewhere that only United was affected among the US carriers. Is that no longer true?

                                  • impish9208 2 days ago
                                    • appendix-rock 2 days ago

                                      As usual, anyone without prior familiarity should take all “Boeing News” with a huge grain of salt, because outrage merchants / people trying to look smart get a kick out of spreading very BAU things as if they weren’t.