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UK air traffic control meltdown

jameshaydon.github.io

11–20 of 459 posts

Re: UK air traffic control meltdown

#12

And why could the system not put the failed flight plan in a queue for human review and just keep on working for the rest of the flights? I think the lack of that “feature” is what I find so boggling.

To be fair, the article suggests early on that sometimes these plans are being processed for flights already in the air (although at least 4 hours away from the UK).

If you can stop the specific problematic plane taking off then keeping the system running is fine, but once you have a flight in the air it's a different game.

It's not totally unreasonable to say "we have an aircraft en route to enter UK airspace and we don't know when or where - stop planning more flights until we know where that plane is".

If you really can't handle the flight plan, I imagine a reasonable solution would be to somehow force the incoming plane to redirect and land before reaching the UK, until you can work out where it's actually going, but that's definitely something that needs to wait for manual intervention anyway.

Re: UK air traffic control meltdown

#14

"the description sounds like the procedure is working directly on the textual representation of the flight plan, rather than a data structure parsed from the text file. This would be quite worrying, but it might also just be how it is explained." Oh, this is typical in airline industry work. Ask programmers about a domain model or parsing, they give you blank stares. They love their validation code, and they love jus…

Giving up if something doesn't validate is indeed standard to avoid propagating badly interpreted data, causing far more complex bugs down the line. Validate soon, validate strongly, report errors and don't try to interpret whatever the hell is wrong with the input, don't try to be 'clever', because there lie the safety holes. Crashing on bad input is wrong, but trying to interpret data that doesn't validate, without specs (of course) is fraught with incomprehension and incompatibilities down the line, or unexpected corner cases (or untested, but no one wants to pay for a fully tested all-goes system, or just for the tools to simulate 'wrong inputs' or for formal validation of the parser and all the code using the parser's results).

There are already too many problems with non-compliant or legacy (or just buggy) data emitters, with the complexity in semantics or timing of the interfaces, to try and be clever with badly formatted/encoded data.

It's already difficult (and costly) to make a system work as specified, so subtle variations to make it more tolerant to unspecificied behaviour is just asking for bugs (or for more expensive systems that don't clear the purchasing price bar).

Re: UK air traffic control meltdown

#15
The fact that they blamed the French flight plan already accepted by Eurocontrol proves that they didn't really know how the software works. And here the Austrian company should take part of the blame for the lack of intensive testing.

Re: UK air traffic control meltdown

#16

Of course they blamed the French ^^

[flagged]

Well that's DailyMail for you, where they tag anything parenting or healthy as "femail" section... cause you know only women are looking at that stuff.

Lol.

Anyways I actually think that's just reasonable response, system goes down/related system goes down , and in reviewing they are making frivolous updates to names that aren't needed.

I would question these updates (while they may be minor part of overall updates occuring).

Re: UK air traffic control meltdown

#19
Software has bugs, that's not really the damning part... The damning part is that in four hours and two levels of support teams, there was noone who actually knew anything about how the system worked who could remove the problematic flight plan so that the rest of the system could continue operating!

What exactly is the point of these support teams when they can't fix the most basic failure mode (a single bad input...)

Re: UK air traffic control meltdown

#20

Of course they blamed the French ^^

[flagged]

Except that was a completely different incident and it occurred in the United States, not the UK. The Daily Mail did try to make hay out of the idpol angle, but the British can't reasonably be accused of shirking responsibility for the FAA grounding flights in the US.
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