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And all that expensive engineering is still less costly AND faster (!!) than a new software certification.

Cannot refrain myself from asking why ...


Situation: Software-1 on Platform-1, both certified.

Time-evolution: P1 is deprecated, replaced by uncertified P2, but S1 remains certified.. just nowhere certified to run yet.

Solution: There's another software S2 which originally vouched for P1, itself still certified, which can still be used to certify P2.

Counterfactual?: If S1 were deprecated in favor of new S3.. there'd be no plan to certify it!

The problem: None of this actually makes any sense! But we're trying to fake due diligence. Everyone knows the hardware/platforms kinda need to be certified with respect to each other anyway, but if we did it that way it would all be even more expensive an time-consuming.


Doesn't seem crazy to me. Which one do you suppose needs more proof of correctness: a cake recipe, or the oven you bake the cake in? The recipe has to be correct or the cake won't work, but the oven just has to hold a temperature.

Ovens vary greatly. There is no consistency in how even the heat is in the space, the airflow through the space, how much and how fast the temperature varies around the set temperature, etc. These things all do affect how things bake up and often people have to tweak recipes for their specific oven.

In a case where something is safety critical the computer is super important as very subtle errors could cause catastrophic consequences. This is why you get into things like running software on 3+ computers concurrently depending on how fail-safe something has to be.


That "just" is quite the load-bearing seam ...

Particularly when the task here is "just" to measure some rod positions in a constrained 3D space ...


How much do you think it costs, in total, per prisoner today, per year?

Yeah. A one-shot investment of 10k$ per prisoner to avoid more manslaughter cases is peanuts, really.


Cool! Can I use them without any meta or facebook account?


That's available to all provinces, so unless quebec invoked it to bypass all clauses of the charter, it's still accurate to say they're subject to it. Otherwise you can say that ontario isn't bound by the constitution either, because they can theoretically invoke that clause.

This is likely the consequence of that : https://www.ctvnews.ca/montreal/article/montreal-police-mayo...

The police woman is amazingly patient.


That concerns more than 220 million people in the USA, who can be arbitrarily stopped in the street and searched.

Be afraid...


...which is about 2/3rds the population of america.

We are not living on the same planet.

I do not want cheaper, I want quality at a reasonable price. Sometimes I even accept an unreasonable price for the quality (think Apple stuff). I will never buy crap at cheapest bargain prices.

Cheap clothes barely survive a couple of washes, good quality clothes survive much, much longer. Yes, they are more expensive short term, quite a bit less expensive long term.

Also, not once, ever, was my buying decision influenced by an ad. What influences my decisions is the problems, the defects i will have, or not, with what I chose to buy. Usually, the longer time it works the more expensive it is.


With that kind of protection it is guaranteed that that no Flock camera will ever be sold in Europe after december 2027... CRA et al...

I wonder what would happen if one of their customers asked for a 62443-4-2 certificate of compliance?


I would love to see someone better than me at CAD design propose a 3D printable model of that clock!


You would be surprised at what AI can do now, it may be possible to use it for this purpose.

This file is similar, but not the same: https://www.thingiverse.com/thing:3407682


That file doesn't seem like it would work for a number of reasons.

The gear with integrated hour hand wouldn't be able to rotate in the space that it's mounted. In order to tell the time against the ring, the hand would need to be much further away from the gear.

Secondly, the funnel bit seems to have no real purpose; if you have to pipe water to the funnel, why not just bring it directly to the cup at the bottom? In real water clocks there is usually a primary collector but it's built in such a way that it overflows at a certain level so that the pressure on the outgoing line stays constant. The funnel here does essentially nothing and there is nothing else in the clock that would provide any kind of flow rate calibration; you'd have to do that externally.

Lastly, it's not clear how you'd reset the clock. Can the collector be removed separately or do you need to turn the whole clock upside down to pour the water out and get the float back down to the bottom?


That is unfortunate. Sorry to have shared one that is crap. I don't have a 3D printer to test.

Catastrophic failure? Check

Plane landed without casualties? Check

Plane design so good it helped avoid casualties? Check

Hum... Ah! Not an american Boeing but a french Airbus. Of course.

The article mentions this story should make everyone a little less afraid of flying.

Sure, as long as its not on a Boeing plane.


Like Boeing, there was organizational dysfunction leading to a direct safety issue.

During the development of the A380, the German and French sides were using different versions of the CATIA PLM software (i.e. CAD), which prevented people from looking at a single unified model of the plane. One concrete problem it caused was major problems with the wiring harnesses, which led to a 2 year delay in the program, and 3 early A380's which couldn't be sold. (Airbus kept one for test, the other two got sent to museums)

That manifested in this accident because the wing wiring was routed through the engine disk burst axes (a hazard which is explicitly accounted for) with insufficient redundancy. That created the dangerous situation where they couldn't turn off the engine after landing.


Thanks for mentioning the A380 CAD snafu, it made me rewatch one of my favourite clips [0].

The guy taking his hat off makes me burst into nervous giggles every time lol.

[0] https://www.reddit.com/r/interestingasfuck/comments/1k80h9j/...


Here's the companion, "we promise we fixed it."

https://www.youtube.com/watch?v=WBbA9uKP-mA


> That created the dangerous situation where they couldn't turn off the engine after landing.

Which is vastly preferable compared to all of the dangerous situations just prior to that landing.


The vastly preferable situation was to have redundant wiring that properly complied with regulations, which was retrofitted in an airworthiness directive (safety recall) after the accident.

They also required engine software that detected the sudden increase in speed associated with a shaft break and automatically cut fuel.


Sort of. Rolls Royce voluntarily developed this software modification in response to learning that their reasoning about it never being able to happen was incorrect and being unable to concretely account for how it happened. EASA, which was not even the relevant safety authority for this incident, upon learning of its existence, only then required it to be installed on all A380 Trent 900 engines.


The plane was a significant factor but you really shouldn't look past the calibre of expertise in the cabin on this particular flight.

> 5 pilots were in the cockpit of this flight. In addition to the normal crew of pilot-in-command and co-pilot, there was an experienced relief pilot and two additional check captains; one was being trained as a check captain (CC) and the supervising CC, who was training the CC.

Captain Richard Champion de Crespigny had 35 years of flying experience at the time of the incident.

That is an insane amount of flight experience in the cockpit and all of the reports state this was a very significant factor. i.e by allowing distribution of the task load, plenty of time for one of the pilots to compute landing calculations manually etc.

THe A380 is a flying tank no doubt, but it wasn't the sole factor here - I think most people would agree this one was a shared victory.


It was probably helped by the fact that airbus didn’t try to pretend that the aircraft was just a slightly different version of some previous aircraft and therefore doesn’t require any additional training lol.


Read about the AF447 Rio-Paris crash. Input stick averaging?? That's a huge design mistake which contributed to the crash and AFAIK is still here..


What’s the alternative? I think averaging with a dual input alert is a pretty good solution. Otherwise you need to find a solution to transition from one stick to the other. You can’t just switch sticks with the press of a button because the input could jump from elevator up directly to elevator down for example.


You give them direct feedback and eliminate the need for this completely


Airbus is French, German and British. Not just French.


The state-held stakes are mainly French, German and (less) Spanish. The UK taxpayer currently owns 0% of Airbus, though the UK gets the business of building wings and landing gear.


An aviation thread with two utterly ignorant posts - [0]. Is that the aviation knowledge level of HN?

[0] - this one and https://news.ycombinator.com/item?id=49541946


I thought this was a strange insertion of geopolitics into the conversation so I checked out this account’s comment history. It’s good for others to see that some commenters here have a serious axe to grind and are not really “hackers” as their primary interest here. The most recent comments in order:

> [something about london taxi drivers, admittedly unrelated]

> I totally get you and in theory you are right. And yet, in the USA you have gerrymandering and apparently _wanted_ Trump. Twice. Something has to be very wrong somewhere.

> I would suggest "lobbying" is not the correct word to describe all the corruption going on in the current USA administration cesspool.

>I recently bought a BambuLab 3D printer. Designed and made in China. Right from the unpacking to first print the experience was top Apple-style quality. Indeed I was agreeably surprised.

> A global non USA success? Plenty. You might want to remove your pink USA glasses and look around. Spotify good enough for you?

> I am Canadian. Never, ever would i knowingly buy any dairy products from the USA , at any price. We have cows too, and farmers.

> Its not that it hates its customers , as much as it it a USA-based company that is run under the rules made by the administration. Not that much different from running Red Star OS from North Korea, actually.

> [Finally something unrelated]


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