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UK air traffic control meltdown

jameshaydon.github.io

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Re: UK air traffic control meltdown

#221

Post by seabass-labrax »

johnklos wrote: post #214

So the "engineering teams" couldn't tail /var/log/FPRSA-R.log and see the cause of the halt? I've had servers and software that I had never, ever used before stop working, and it took a lot less than four hours to figure out what went wrong. I've even dealt with situations where bad data caused a primary and secondary to both stop working, and I've had to learn how to back out that data and restart things. Sure, hind…

You're assuming that there is in fact a /var/log/FPRSA-R.log to tail - it would not at all surprise me if a system this old is still writing its logs to a 5.25 inch floppy in Prestwick or Swanwick^1.

^1: they closed the West Drayton centre about twenty years ago; I don't imagine they moved their old IBM 9020D too, if they still had it by then. My comment is nonetheless only slightly exaggerated ;)

Re: UK air traffic control meltdown

#222

Post by schainks »

dundarious wrote: post #105
rglover wrote: post #95

Earlier quoted context omitted.

No change at all? I find that hard to believe. There's also a data design problem here, but the structure of JSON would aid in, not subtract from, that process. The question at hand is: "heavily structured data vs. a blob of text as input into a complex algorithm, which one is preferred?" Unless you're lying, you'd choose the former given the option.

The issue is using both ADEXP and ICAO4444 waypoints, and doing so in a sloppy way. For the waypoint lists, there is no issue with structurelessness -- the fact that they're lists is pretty obvious, even in the existing formats. Adding some ["",] would not have helped the specific problem, as the relevant structure was already perfectly clear to the implementers. I am not lying when I say the bug would have been equa…

Now I'm wigging out to the idea of how the act of overcoming the inertia of the existing system just to migrate to JSON would spawn thousands of bugs on its own — many life-threatening, surely.

Re: UK air traffic control meltdown

#223

Post by gavinsyancey »

sam0x17 wrote: post #163
reactordev wrote: post #28

So they forgot to "geographically disparate" fence their queries. Having built a flight navigation system before, I know this bug. I've seen this bug. I've followed the spec to include a geofence to avoid this bug.

Why on earth do they not have GUIDs for these navigation points if the names are not globally unique and inter-region routes are commonplace?

It sounds like for actual processing they replace them with GPS coordinates (or at least augment them with such). But this is the system that is responsible for actually doing that...

Re: UK air traffic control meltdown

#224

Post by ivraatiems »

lozenge wrote: post #191
Thorentis wrote: post #184

Earlier quoted context omitted.

Except that you can't be sure this bad flight plan doesn't contain information that will lead to a collision. The system needs to maintain the integrity of all plans it sees. If it can't process one, and there's the risk of a plane entering airspace with a bad flight plan, you need to stop operations.

But they have 4 hours to reach out to the one plane whose flight plan didn't get processed and tell them to land somewhere else.

Assuming they can identify that plane.

Aviation is incredibly risk-averse, which is part of why it's one of the safest modes of travel that exists. I can't imagine any aviation administration in a developed country being OK with a "yeah just keep going" approach in this situation.

Re: UK air traffic control meltdown

#225

Post by seabass-labrax »

I had been considering becoming an air traffic controller myself, and it rather tickles me to think I might have missed my once-in-a-lifetime opportunity to direct aircraft with the original pen-and-paper flight strip mechanism in the 21st century! Completely safe, excruciatingly low-capacity, and sounds like awfully good fun as a novelty (for the willing ATC, not the passengers stuck on the ground, I hasten to add).

Re: UK air traffic control meltdown

#226

Post by johnklos »

slingnow wrote: post #220
johnklos wrote: post #214

So the "engineering teams" couldn't tail /var/log/FPRSA-R.log and see the cause of the halt? I've had servers and software that I had never, ever used before stop working, and it took a lot less than four hours to figure out what went wrong. I've even dealt with situations where bad data caused a primary and secondary to both stop working, and I've had to learn how to back out that data and restart things. Sure, hind…

Damn, if only you had been there to instantly save the day by just running that simple command!

No. That's silly. The logs would've / should've just shown that the program halted because it was confused about data. The actual commands to fix would've been quite different.

Re: UK air traffic control meltdown

#227

Post by dopidopHN »

hermitcrab wrote: post #197

>"in typical Mail Online reporting style: "Did blunder by French airline spark air traffic control issues?" The Daily Mail is a horrible, right-wing paper in the UK that blames 'foreigners' for everything. Particularly the French. Out of curiosity, is there a corresponding French paper that blames the English or the British for everything?

French here, as much as I wish It was the case for comical effect… I don’t think so.

Our right wing press is also desperately economically liberal so anything privately run is inherently better.

Maybe radio stations? Honestly, major respect to the daily mail for those snarky attacks that keep up the good spirits between our two countries.

It’s maybe the food or the weather that make them aggro ? Idk, but don’t worry, we love to hate the perfide Albion. Too.

Fellow French: am I wrong ? Maybe “valeur actuelle” could pull up that type of bullshit, but I think they are too busy blaming Islam to start thinking about our former colony across the channel.

Re: UK air traffic control meltdown

#228

Post by jakub_g »

count wrote: post #164
rglover wrote: post #104

Earlier quoted context omitted.

I haven't, but I'd love to. My approach wouldn't be very "HR friendly," though.

Ah yes, migration through sheer force of will.

It's trivial. Only took Amadeus hundreds of developers working for over a decade to migrate off TPF. /s

[0] https://amadeus.com/en/insights/blog/celebrating-one-year-fu...

Re: UK air traffic control meltdown

#229

Post by rglover »

count wrote: post #164
rglover wrote: post #104

Earlier quoted context omitted.

I haven't, but I'd love to. My approach wouldn't be very "HR friendly," though.

Ah yes, migration through sheer force of will.

In some sense, yes. Notice that most of the responses to what I've said are immediately negative or dismissive of the idea. If that's the starting point (bad mindset), of course nothing gets fixed and you land where we are today.

My initial approach would be to weed out anyone with that point of view before any work took place (the "not HR friendly" part being to be purposefully exclusionary). The only way a problem of this scope/scale can be solved is by a team of people with extremely thick skin who are comfortable grabbing a beer and telling jokes after they spent the day telling each other to go f*ck themselves.

Re: UK air traffic control meltdown

#230

Post by seabass-labrax »

teleforce wrote: post #218
codeulike wrote: post #153

This is a great post. My reading of it: - waypoint names used around the world are not unique - as a sortof cludge, "In order to avoid confusion latest standards state that such identical designators should be geographically widely spaced." - but still you might get the same waypoint name used twice in a route to mean different places - the software was not written with that possibilty in mind - route did not compute…

Thanks for the summary and TL;DR. Essentially this is down to the lack of proper namespace, who'd have thought aerospace engineer need to study operating systems! I've a friend who's a retired air force pilot and graduated from Cranfield University, UK foremost post graduate institution for aerospace engineering with their own airport for teaching and research [1]. According to him he did study OS in Cranfield, and n…

It sounds like a great place to study that has its own ~2km long airstrip! It would be nice if they had a spare Trident or Hercules just lying around for student baggage transport :)
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