@AC-fail: It's all about the monies

If this is the only unplanned outage this year they'll still have five nines. Even if it's not, the cost of those last fractions of a percentage point become progressively more expensive so it might not be worth it. How much extra are you prepared to pay for a ticket to avoid a 0.001% risk of standing in line for a few hours more, esp. considering that this is not the only factor that can lead to excessive queueing in Stansted? I thought so...

SBO

No, I am sure nobody in the entire history of the airline industry ever thought that high availability systems might be a good idea. It's a good job there are people like you around to point us in the right direction.

In fact if the facts are accurately reported and both internet and airport check-in were down then it is likely to be a failure in the back-end passenger services system of one specific airline. In general these are airline-specific rather than utilities provided by airports (although there are exceptions). These back end systems have typically four nines availability or better although there are variations between the mainframe systems used by traditional airlines and the .NET based Newskies used by Ryanair and others. Life gets more complicated when check-in is being managed by a ground handler rather than the airline itself although that isn't likely to be the case here as a ground handler's system failing would not have affected web check-in.

It is also extremely unlikely that anyone at the airport would have been in a position to "reboot" the system even if they had wanted to as check-in systems usually live in vendors' data centres that are often not even in the same country.

There's still hope

It could have been a fellow sysadmin - they are allowed to be of the female persuasion these days, you know. Let us hope it is so. Or we are indeed doomed.

is required.

Funny euphemism for porn that.