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Comment by ekianjo | Hacker News Reader

Yeah, because we know governments are really good at giving certifications and doing tests that mean sonething. Lets put every design decision in the hand of governements then! or better, nationalize car companies! Problem solved?

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Flying in an airplane is safe because of direct intervention by the government.

Cars have been made safe for us also by direct intervention by the government. From important things like mandating seat belts and crash safety to smaller things like forcing the recall of tens of millions of faulty air bag inflators.

These are just a few of the many things Uncle Sam has done to make things safer for us.

Isn’t flying mostly safe because of post hoc safety analysis followed by operating requirements? I don’t think the FAA tests every change made to aircraft before they can fly?

De facto the FAA indeed does that very thing.

First, any change in design (or in configuration, in the case of repairs) is backed by PEs or A&P mechanics who sign off on the changes. Their career rides on the validity of their analysis so that's a better guarantee than some commit message by a systems programmer.

Second, the FAA basically says "show us what you are changing" after which they will absolutely require physical tests (static or dynamic tests, test flights, etc., as appropriate to the scope of change).

And I'd say flying is so safe mainly from the blameless post-mortem policy that the American industry instantiated decades ago and which is constantly reinforced by the pros in the NTSB. It's a wonderful model for improvement.

I think that the FAA's role is theoretically as you express, but in practice, there is significantly less oversight (especially direct oversight) than implied.

As an example, the crash of N121JM on a rejected takeoff was due (only in part) to a defective throttle quadrant/gust lock design that went undetected during design and certification, in part because it was argued to be a continuation of a conformant and previously certificated design. (Which is relevant to the current discussion in that if you decide to make certification costly and time-consuming, there will be business and engineering pressure to continue using previously certificated parts, with only "insignificant changes".)

https://aviation-safety.net/database/record.php?id=20140531-...

PS: I 100% agree on the NTSB process' contribution to safety.

That's fascinating, it's kind of a collectivizing of the responsibility for safety.

If I, as an engineer, sign of on changing the screws on the flaps for cheaper ones and the plane crashes because the flaps go loose due to the screws being unable to handle the stress, my career can be assumed over if I have no good explanation.

If an engineer signs off a change they sign that they have validated all the constraints and that for all they know the machine will work within the specs with no faults.

If a software engineer commits code we may run some tests over it, look a bit over it. That's fine. But if the software ends up killing anyone, the software engineer is not responsible.

And yes, to my knowledge, every change to an aircraft is tested before flight or atleast validated by an engineer that understands what was just changed.

In any case, let a third party control the actual updating, so that we know when and how often cars are updated. Require at least X months of time between code submission and deployment to cars. We don't want a culture of "quick fixes".

This is a popular idea: Just put someone in charge! It ignores the incentives for those gatekeepers, who are now part of the system. In practice I don't think you're going to get better updates, you're going to get "almost no updates".