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Comment by jsprogrammer | Hacker News Reader

We actually don't allow planes to crash. Crashes are a result of human error or catastrophic failure. When a crash occurs, the cause is investigated so that another crash never happens for the same reason. If a defect is ever found, all affected planes are grounded until they have been fixed.

I expect Autopilot to be disabled soon.

Edit:

>So basically we accept that in order for each of us to fly to our destination, 300 ish people must die every so often. Like a kind of sacrifice.

Your position is...crazy.

No plane will take off if there is a calculated chance that it could crash.

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There are many factors that can never be anticipated and we explicitly accept that they still exist.

>No plane will take off if there is a calculated chance that it could crash.

I don't get this comment. If there are statistics that prove one in every X million planes crash, then every plane taking off has a 1 in X million chance of crashing.

There is actually a very precise calculated chance that it could crash (but air travellers generally accept it).

>> No plane will take off if there is a calculated chance that it could crash.

So, planes have a 0% chance to crash when they take off?

On the contrary, every plane that takes off does so despite the known chance that it could crash.

No. I am talking about calculated chances, not "someone might decide to crash the plane" chances. If there is a known chance that a component of a plane might fail and cause a crash, it will not take off.

>> If there is a known chance that a component of a plane might fail and cause a crash, it will not take off.

There is no component of any machine that is 100% guaranteed to not fail under any circumstances. What the bloody hell are you talking about?

Known, calculable circumstances. If a component may fail, then redundancies are added so that failure will not result in a crash.

You just keep digging. All adding redundancy can do is lower the chance of a crash.

> If a component may fail

As has already been pointed out to you, all components may fail, including any that you add to compensate for the potential failure of other components.

An engineer should know this by instinct.

An engineer should know nothing by instinct.

Adding redundancy was incorrect. Redundancy should be inherent to the design. If one must be added, the design is already a failure.

Redundancy does not mean adding a new component, but maintaining operation under component failure. For example, if the engines fail, it should still be possible to make a controlled landing.

If you can build an airliner with 100% failsafe redundancies at a cost that makes you competitive with the incumbants I'll be the first to buy a ticket. Heck, I'll be the first to invest.

Nothing is 100% failsafe. Machines can be designed that will not enter known failure modes, given they are operating in within known conditions. If such a machine is detected to be able to enter a failure mode in expected coming conditions, it should not be used commercially.

Cf. The grounding of all Boeing 787s: https://en.m.wikipedia.org/wiki/Boeing_787_Dreamliner_batter...

"Redundancies are added"? Sorry but you just made that up. If the risk of an accident and death was "calculable" in the way you're trying to say it is, we wouldn't "add redundancies". We'd just avoid flying (or driving) and nobody would ever die in an accident.

Wrong.

One in 1.2 million flights crash. This is literally a "known chance".

Planes take off anyway.

No, that is an observed statistic.

And the difference is?

One is predictive, the other is retrospective.

Except that the retrospective IS predictive.

What evidence supports that position?

Crashes are anaomolus events that happen for very specific reasons. Reasons that do not have any seeming connection to any other crash. I don't see how a retrospective could predict anything about the success of future flights.

https://en.wikipedia.org/wiki/Failure_rate

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