Comments by "Mikko Rantalainen" (@MikkoRantalainen) on "WHAT Is going ON with Boeing?! MAX-9 Door blowout" video.

@alanevery215 Successful as in meeting minimum bar required to build Boeing airplanes.
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Seems legit!
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So, basically any silicon or TPU case which covers all the edges of the phone should be equally good for this use case? If you don't mind the usability issues, something like Otterbox where the protective edge comes off the screen quite a lot would guard the glass pretty well. Of course, that also makes all the touch gestures starting or ending at the edge of the screen next to impossible to execute.
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And if it hits some kind of bush instead of landing directly on grass, there's no need for a case at all.
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And definitely not let the aviation companies to decide if the existing type certification for the older model is usable for next model. This far MAX has had at least features such as MCAS and cockpit door opening by itself on depressurisation that haven't been disclosed to pilots on "no need to know" basis – I would assume to make FAA accept that no additional training is required.
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@razvanlex When you meet somebody with a cracked screen, do you think they have been living within bushes and soft grass. Or in concrete jungle?
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@sarthakmohanty997 I wouldn't be surprised if it turned out that Boeing management has similar problems as NASA did with the shuttle. If I remember correctly, NASA had a problem that engineering thought that there's about 1 in 100 change for life loss for any given shuttle mission (that is, the shuttle is 99% safe) and the management thought that there's about 1 in 1000000 change for life loss for any given shuttle mission (that is, the shuttle is 99,9999% safe). If you assume that the risk is 1 in million, you may get less strict about the details such as outdoor temperature and humidity during the launch or QA verification steps needed for the door plug.
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@ironcito1101 3 mm thick case might be enough even with somewhat slow terminal velocity if crash direction is perfect. That is, no bending forces from the hit, glass never touching anything hard. I wouldn't be surprised if the phone can take at least 100g without breaking . If we assume that the terminal velocity of a smartphone is around 50 m/s and the 3 mm bumber being flattened therefore takes about 0.00006 seconds, the resulting g-force for the stop is about 85g. If the hit is corner first, the g-force may bend the phone which will obviously crack the glass parts.
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Yet another MAX "pilot's don't need to be told about this change" feature, right? I get upset when I don't have a truthful changelog for the software I use, I would expect pilots to be asking for even more!
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Wow! Yet another example of MAX "pilots will not need any additional training" decision that was made by the marketing and management without discussing about the reality with the engineering. I would be very careful with any "pilots will not need any additional training" style marketing speech from any manufacturer in case of changes to the aircraft design.
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@secondskins-nl I'm pretty sure a smartphone terminal velocity should be at least the same level as a human (~40 m/s). My point was that even if we assume 50 m/s velocity and 3 mm stopping distance, it's still "only" 85 g. That would kill a human but a smartphone should be able to take that much acceleration if the force is applied evenly to the whole body of the smartphone instead of only one corner.
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@awdrifter3394 I think the situation with MCAS was different in that the marketing and management had already decided that additional pilot training is not an option even before the engineering had figured out if that's actually possible. And the angle of attack (AoA) sensor couldn't be made mandatory part because that would have made that critical part of the aircraft, which will always require mandatory training. So that option was off the table because of political decision that marketing or management had already made without understanding the consequences. This time it appears more probable that the problem was error in manufacturing and that was not caught because of incorrectly designed or implemented QA process. It doesn't seem that there was any reason for politics to prevent doing that part correctly, unlike with MCAS.
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@JohnnyWednesday Why do you believe that "the sensors are more sensitive the closer the pressure is to ambient"? I would assume they are using solid state absolute pressure sensors (similar to automotive) and those have nothing in the design that would make them more accurate close to 1000 mbar absolute pressure. The sensor should output about 250 mbar absolute when the aircraft is flying at 33000 ft.
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The door is pretty flat object and would probably glide in the air. The initial orientation in the air probably defines which way it will glide.
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@Ldavies2 Or simply raise the licensing fees to make the plane manufacturers to pay for their planes?
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@jujuu1339 I would argue that no smartphone or screen protector is 9H for real. In marketing materials, sure, but if you actually test scratching it, nope.
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