As a big company, making several hundred thousand flights a year, it will be hard to always arrive at alternate and land with >30 min of fuel left, if the whole company only tanks minimum. Situations in aviation are too divers to judge from your own experience to the overall system level.
Example: if all the operators into FRA fuel minimum, and all have the same closest alternate filed, imagine what happens at this low capacity alternate when the whole wave has to divert on minimum?
And still all the European flights are planned with the minimum amount and judging by the (lack of) ASR's, very few flights land with less than 30 minutes. And with very few, I mean not a handful on 100.000+ flights a year.
But to be honest, and I forgot this point, we do, if the price is right, tank the amount neede fot the way back (if flying to a "expensive" airport. But that would leave us with minimum again for the way back.
And I do fly to FRA regularly, and in 90% of the time with minimum fuel, taxiiing in with altn+30 minutes left. And again, I don't see a problem in that,
providing you keep up te date with the circumstances around you.
Half an hour before landing we check the weather. Is it iffy? Check more than one airport around you. Depending on the distance the planned alternate does not have to be the best option on that day. Make a calculation for each suitable airport, and there are always more then one in my part of the world, when you want to divert to that airport to arrive with at least 30 minutes of fuel. Do you hear a lot opf diversions to that airport? Plan for a earlier leave of the holding...
Would I know only one other airport would be suitable and therefore very busy, then offcourse I would take more, but going from my homebase to FRA gives me a suitable alternate every 25 miles, giving me an option every 25/GS minutes.
Would FRA completely close during my approach after having flown not a shortcut or such, having burned exactly the flightplan fuel plus the cont fuel of at least 5 minutes and my altnernate would also have unforseen delays, then I agree I am getting close to the limit, but to be honest, that's such a small chance it is not weighing up to taking 200KGs or more on every single flight. And flying in this busy space for 10 yeasr hasn't given me one moment where I was out op options and had to land with less then 30 minutes.
Might have been lucky and past results are never assurances for the future, but taking more/too much fuel does not make for a safer flight (but it does make it easier).
the stranger.
Fog and indeed TS can occur unexpectedly. You deal with it just like you've said.
The point is setting off to an area of known Fog or TS (in my opinion similar as they stand a good chance of improving within 30min) on min fuel is fool hardy. Especially like in this case to a busy Hub.
Fuel gives you time to gather information and make the safest and most commercially viable decision. It also gives you flexibility to change your decisions before you end up going deeper into your tunnel vision. Any pilot who has experienced options blinking out around them due to changing circumstances knows the value of this.
Putting yourself knowingly into a stress inducing scenario before even getting airborne is something that should be left to fighter jocks.
I don't know what other people do, but when knowing the destination is not great weatherwise, I start making plans early during the flight, of not before the flight. That does not create stress, it is part of my normal job. I do not wait until I pratically see the airport
Our flights range typically from an hour to an hour and a half. With ACARS, I can be updated on weather from the moment I get airborne for all airports within reach. With VHF and ACARS I can talk to handling on destination to get an idea if there are a lot of diversions, holdings etc.
Within 10 minutes after the after t/o checklist I can have an altered plan, selected my actual alternate (which might be different than on the flightplan, reducing the required fuel) and have a good idea of the traffic there (ATC does help you know in giving info on how many have diverted to that field). Still got at least 30 minutes left before we start an approach. Time enough to adjust the plan if needed.
And this way of planning would be the same if I had minimum fuel or 1 hour extra. I always know when to divert to land with 30 minutes left and that moment is almost always (far) earlier the moment where I am left with altn+final reserve.
I am talking about a situation where only the destination is difficult, weather or traffic wise, giving me options all around me and the destination. Things chance, as would the amount of fuel in my tanks, if the trouble is allready at more than one location.
But the way I have been working, as have most of my colleagues has not given one low fuel emergency for the last 4 years, nor do we divert a lot. But we do save a lot of fuel and save more every year by looking professionally at our required fuel instead of just taking extra.