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0 pointsviraptor9mo ago0 comments

Unfortunately that's not how things work in practice https://en.wikipedia.org/wiki/Split-brain_(computing) If Jepsen fails every database coming from single source, imagine the chaos of synchronising a P2P of various clients of various versions over a very noisy link. We can't even achieve that with home automation meshes that send maybe 3 types of messages!

Also you need to handle planes without computers - you can land a personal plane at almost any airport. (With lots of caveats but still) Also you need to handle planes with failing automation. Also you really want to know the situation on the runways, so there's really no need to remove the single source of truth here.

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fallingknife9mo ago

We operate cars on the road with not only no centralized system, but also minimally defined and enforced protocol, and yet Waymo has achieved a near zero collision rate inside a swarm of cars that are not running equivalent software. And this is in a situation where cars are only a few feet from each other while operating at top speed. So you can come up with a million objections but they are all solvable. As for automation failure, the rate of that can be easily made lower than the rate of human failure, which currently is fatal to a plane.

const_cast9mo ago

Waymo is significantly more dangerous than air travel to a degree that the comparison is actively offensive to everyone currently alive on Earth.

We can't even get cars, working in more-or-less two dimensions, to go without constantly running into each other and being one of the major causes of death in human civilizations. Waymo "solved" that problem in about, oh let me see here... yeah 0.0001% of cases. So, we're almost there! That's, like a couple cities out of all cities on Earth.

Yeah that's bad. Really, really, really bad. Like so bad it's not even worth talking about and comparing to air travel.

viraptorOP9mo ago

That's a completely different system. In a car everything still resolves in seconds and needs minimal planning -corrections can happen in real time. That's completely different from "there's a queue of planes coming in and you have to manage the throughput available on the ground". You can't just hit emergency breaks on everything and slowly resolve the situation. These things are not comparable.

lurking_swe9mo ago

99.9% success rate is probably not good enough when you consider that the vehicle in question costs $200 million, and has 150 - 350 humans on board. It’s not a “whoopsie” like with cars where the damage is $50k at most (waymo vehicle) and maybe 2-3 people injured or dead. Also dead pilots who are already in short supply.

Also cars only care about what’s going on in a horizontal plane. 3D space is clearly more complex and probably requires more computational power i’m sure. Consider that boeing couldn’t even correctly write software to keep their 737 MAX planes from crashing into the ground (MCAS software issue). Something that simple was too hard for them. Speaks volumes doesn’t it?

Not saying it’s impossible. Just saying that this clearly isn’t a “just do it” problem. Waymo’s been working on their software for how many years now? and they still have minor crashes lol. Not an easy problem at all.

Also consider that airlines usually outsource their software development so they don’t have cutting edge expertise in house.

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