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Comment by f1shy | Hacker News Reader

As an engineer I think a lot about tradeoffs of cost vs other criteria. There is little I can learn from nuclear or aviation industry, as the cost structure ist so completely different. I’m very happy that the costs of safety in aviation are very good accepted, but I understand that few people are willing to pay similar costs for other things like, say, cars.

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The costs of the Fukushima and Deepwater Horizon were very, very high. Both could have been averted at trivial expense with simple changes to the design.

Fukushima:

badthink - the seawall is high enough that it will stop tidal waves

goodthink - what happens when the seawall is overtopped? Answer: the backup generators drown. Solution: put the backup generators on a platform.

Deepwater Horizon:

badthink - the pipe is strong enough to never break

goodthink - what happens when there's enough force to bust the pipe off? Answer: the pipe flow cannot be shut off. Solution: put a fuse (a weak spot) above the valve, so when the pipe busts off, it breaks above the valve, and the valve can be turned to shut off the flow. (The valve was located on the sea floor.)

This is so easy in retrospect when you know what the failure mode will be.

badthink: the Fukushima backup generators must be placed on a platform to keep them out of the range of a once in a millenium tsunami

goodthink: what happens when a typhoon comes and damages the generator on an exposed platform; an event which happens predictably and far more often than tsunamis. Answer: put the backup generators in the basement of a reactor building behind a large seawall. What catastrophe could put the reactor building completely underwater, and still have the reactor survive?

Yeah, trivial changes to the design can prevent all sorts of disasters, but you have to know what you are trying to prevent in a world of infinite complexity

A large seawall to be sure, but not a particularly tall one. If I recall correctly the seawall was remarkably short relative to maximum expected wave heights on a 100 year time frame.

We're making a niche B2B application, and this is very much it for us as well.

Our customers are in a cutthroat market with low margins. We can't spend a ton on pre-analysis, redundancies and so on.

Instead we've focused reduced the impact of failures.

We've made it trivial to switch to an older build in case the new one has an issue. Thus if they hit a bug they can almost always work around it by going to an older build.

This of course requires us to be careful about database changes, but that's relatively easy.

You can not. AI though, can be cheap enough to produce that. I wonder what happens if you take a b2b application and let it rewrite with AI to Nuclear Industry/ Aviation standards into a seperate repo. Then on fixes/rewrite the engineers take the "safety aware repository" as inspiration.

You’ve missed the point. Those standards don’t relate at all to writing code, they relate to process, procedure and due diligence - i.e. governance. Those all cost a lot in terms of man hours.

Exactly. Even without learning from those groups, there's a ton of stuff we know we could do to improve the reliability of our product. It's just that it would take way too much development time and our customers wouldn't want to pay for it.

It's like buying a thermometer from Home Depot vs a highly accurate, calibrated lab thermometer. Sometimes you just don't need that quality and it's a waste paying for it.

Yeah, it costs. That, and that people will accept shite software makes it high quality a fight software companies can avoid. Rationally therefore, they do.

Have you tried using an LLM to write code to any kind of standard? I recently spent two hours trying to get GPT 4 to build a fiddly regex and ultimately found a better solution on Stack Overflow. In my experiments it also produced lackluster concurrent code.

What you're describing is almost exactly the opposite of what LLMs are good for. Quickly getting a draft of something roughly like what you want without having to look a bunch of stuff up? Great, go wild. Writing something to a very high standard, with careful attention to specs and possible failure cases, and meticulous following of rules? Antithetical to the way cutting-edge AI works.

I don't think that's the right way to reason about it.

I find that I can learn a ton from those industries, and as a software engineer I have the added advantage of being able to come up with zero-cost (or low cost), self-documenting abstractions, testing patterns, and ergonomic interfaces that improve the safety of my software.

In software, a lot of safety is embodied in how you structure your interfaces and tests. The biggest cost is your time, but there are economies of scale everywhere. It really pays to think through your interfaces and test plan and systems behavior, and that's where lessons from these other industries can be applied.

So yeah, if you think of these lessons as "do tons of manual QA", you'll run into trouble resourcing it. But you can also think of them as "build systems that continuously self-test, produce telemetry, fail gracefully in legible ways and have multiple redundancies".

Cars might not be the best example, since human lives are at stake, as in aviation. Unless you work on Teslas autopilot, it seems. But yes, backups and restores are often good enough.

As it turns out (and as much as we wouldn’t want them to) human lives are still subject to cost/benefit analysis.

An airliner is a lot of lives, a lot of money, a lot of fuel, and a lot of energy. Which is why a lot has been invested in training, procedure, and safety systems.

Cars operates in an environment which is in most ways a lot more forgiving, they’re controlled by (on average) low-training low-skill non-redundant crews, they’re much more at risk of “enemy action”, the material stresses are in a different realm, and they’re much, much more sensitive to price pressure.

Hell, the difference is already visible in aviation alone, crop dusters and other small planes are a lot less regulated amongst every axis than airliners are.

I wouldn't say it's simply cost-benefit analysis. It's also scale of accidents.

A whole lot more people die from car accidents, yet there are few reports on national news on accidents. So fewer people care. Meanwhile each time there is an aviation disaster, 100s of people die and it's all over the news for weeks. Similarly with train accidents and nuclear accidents. There where only 2 very large ones but they still haunt the field to this day, while (for example) the deaths from solar installations by people falling from roofs are mostly ignored.

Large accidents have to be avoided, a lot of small ones are more acceptable.

> I wouldn't say it's simply cost-benefit analysis. It's also scale of accidents.

But that is cost/benefit analysis. When any accident can kill hundreds and do millions to billions in damage besides (to say nothing of the image damage to both the sector and the specific brand), the benefit of trying to prevent every accident is significant, so acceptable costs are commensurate.

I think it goes beyond what you'd expect just from the increased scale putting more lives at risk. Compare our regulatory system for buses and cars, two transportation options that are probably as close as possible to differing only in scale. Buses are ~65x less deadly than cars, and yet we still respond to the occasional shocking bus accident by trying to make them safer.

Which is actually counterproductive! This makes it harder to compete as a bus service, bus lines shut down, and more people drive. I wrote more about this at https://www.jefftk.com/p/make-buses-dangerous and https://www.jefftk.com/p/in-light-of-crashes-we-should-not-m...

Any substantiation for "Unless you work on Teslas autopilot, it seems"?

I mean you're implying that there are more accidents with autopilot than without it, right? Seems like quite the claim...

No, I'm implying that the autopilot code has not been as thoroughly tested as it should have been.

Example: https://www.theguardian.com/technology/2023/nov/22/tesla-aut...

Tesla people always try to reduce any critique to some metric on deaths per x.

The fact is, there’s a lot of history and best practice around building safety critical systems that Tesla doesn’t follow.

Additionally, even with the practices they follow, they call a consumer facing product that isn’t really an autopilot “autopilot”, while focusing outbound comms on a beta product that is more like an autopilot, but not available to them.

I agree with most of this but the naming of "autopilot" seems fine. Nobody expects commercial aircraft to fly on autopilot without a pilot's supervision, the same _should_ be true of Tesla vehicles (especially considering their tendency to jump into the wrong lane and phantom brake on the highway etc.)

What matters is what the user of the system thinks because that’s where confusion can be dangerous.

A plane pilot knows very well what the limits of the autopilot are and what the passenger believes is irrelevant.

Conversely if too many/most car “autopilot” users believe it does more than what it really does then it’s dangerous.

In electrical engineering 600V is still “low voltage”. Any engineer in the field knows that so that’s fine right? But if someone sells “low voltage” electric toothbrush or hand warmer no normal person will think “it’s 600V, it will probably kill me”. When you sell something, what your target audience takes away from your advertisement matters. If they’re clearly confused and you aren’t clearing it up after so many years then “confusion” and misleading advertising are part of your sales strategy.

> Nobody expects commercial aircraft to fly on autopilot without a pilot's supervision

Nobody here on HN, because we're really into tech. Outside the tech world, I would guess that 50% of the population thinks that "autopilot" (on any device) means that no human is needed.

Considering Tesla was willing to do unsafe things in visible way (e.g, running stop signs feature), then I have no trust that they are maintaining safety in the less visible ways.

There are a fair amount of backups in your car. For example, the braking system is dual. There's also engine braking and the parking brake that can be used. All the "energy absorbing" features are a backup for when you crash.

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