Hacker News Reader

Update: OK, if *Edinburgh* was their alternate and they missed there and were then forced to bugout for Manchester, that's then an example of when reserve is OK to be burned. (The 'slight simplification' I omitted was unpacking how the alternate fuel plays into the process, but here, that was a key part of the series of events.) That's what I get for not reading TFA first :-/

View on HN

Not really, you should have enough fuel to make it to multiple alternatives or make emergency landing somewhere else. You should never burn that last 45 mins unless you want to make the news and file a lot of paperwork.

The regs are quite specific on if and when we need an alternate, which is weather dependent, and what your fuel requirements are. And we don't really have the idea of "multiple alternatives", but I guess it's implied by the additional reserve - what us Americans call a reserve or the Europeans call "final reserve". In case you're curious, we use the TAF (termimal area forecast) to determine if we need an alternate, and use a 1,2,3 rule which is 1 hour before and 1 hour after arrival time we need ceilings of at least 2000 ft and 3 statute miles of horizontal visibility.

Er.. and maybe crash and kill yourself, all your passengers and crew and people on the ground.

Reply on news.ycombinator.com