In PFPX we have many different rule sets to plan under. The most common ones I use of course are EU and US 121 domestic, since I do a vast majority of flying in either of those two regions.

I know here in the US there is the basic "1-2-3 Rule" wherein the only times you are absolutely required to file and carry enough fuel for an alternate is if:

- ONE hour before and after your ETA, there is a forecasted ceiling of less than TWO thousand feet and/or there is a forecasted visibility of less than THREE statute miles

 

I often apply this to my EU planning as well, though I'm not very familiar with those regulations, and just sort of assume it follows similar reasoning, especially since PFPX allows me to forego filing an alternate under those rules as well. Does anybody else know a bit more about EU alternate regulations?

 

I'm also curious about the rules under other regulations as well; PFPX has a lot of options, ICAO rules, Russian, Australian, etc.

 

Thanks!

IR-OPS CAT.OP.MPA180 b) refers. I can't seem to copy and paste the relevant section for some reason (link to full document here: http://www.skybrary.aero/bookshelf/books/2165.pdf) but essentially you need one alternate unless the flight is:

 

- Less than 6 hours AND

- At least two separate runways are available and usable at the destination AND

- The forecast for the period 1hr before - 1hr after your ETA is at least 2000ft ceiling or circling minima +500ft (whichever greater) AND visibility >5km

 

If the weather at destination is forecast to go below planning minima during the arrival window, or no weather information is available, you need two alternates.