Originally Posted by
KiloAlpha
121 Domestic
The required alternate whether is most likely going to be company specific.
In my case, if the airport has 1 nav aid, then you have to add 400' and 1 mile to the published mins; thus creating "derived" minimums. If the airport has 2 nav aids, then you have to add 200' and 1/2 mile to the published minimums.
Also, keep in mind that there are other alternates besides destination. There are also takeoff, wind, braking, and driftdown.
I have another question under this topic. I understand how you come up with derived minimums that now become you minimum alternate weather requirements. My question is do the alternate minimums posted on the 10-9 pages overide what you came up with on your ops specs?
Here's an example: KRIC 121 ops
If you look on the 10-9A page, it has at the bottom a list of weather minimums for filing it as an alternate. The lowest is 600-2. If I were to use the derived minimums for that airport using ILS 2 & 34, I can get 400-1. So which minimums are the ones you use for filing it as an alternate?
Thanks for the help.