Most US-based airlines were grounded by the Crowdstrike outage on the 19th, but Southwest Airlines was unaffected, because its key systems are still running Windows NT 3.1.

Which is to say, yeah, the OIAR's tech is outdated, but at least it's not Southwest Airlines outdated.

I am going to break my rules for the first time and answer this post that doesn’t technically meet the criteria.

1. Thankyou for telling me this
2. I could tell you some real world horror stories about air travel technical infrastructure. I probably will at some point in the future.
3. The tech for the O.I.A.R. is loosely modelled on actual UK infrastructure and processes I’ve seen implemented in places they REALLY shouldn’t be.
4. The entirety of digital infrastructure is balanced on ancient pins. The reason things keep going is just because there are enough pins distributed about that when something goes ping into the corner of the room there is normally another less optimal pin that can be substituted in a pinch. It’s fascinating, if upsetting, to watch.