# "Landing Minimums"

#### skyhigh600

##### New Member
Hey everyone, quick question...

For part 121 ops it says you need a takeoff alternate if the departure airport is below "landing minimums". Is this referring to ceiling and visibility? Or just visibility on the ILS approach plate?

This term "landing minimums" is also used in stating that no flight may be dispatched to an airport if the weather at time of arrivial is forecast to be below "landing minimums" for that airport. Again, are these "landing mimimums" referring to ceiling and vis, or just vis?

Thanks!

#### SpiraMirabilis

##### Possible Subversive
It means if the departure airport is below derived minimums for whatever the approach is into it.

Second question, only visibility. You can dispatch if the ceiling is overcast at 100, but not if the visibility is lower than the derived minimums for the approach.

#### skyhigh600

##### New Member
So for the first question...if say you depart XYZ and the only approach into there is an ILS that is 200 - 1/2. The ceiling is 100' overcast and the visibility is 3/4 mile. Can you depart without a takeoff alternate?

Thanks again!

#### Buzo

##### Well-Known Member
So for the first question...if say you depart XYZ and the only approach into there is an ILS that is 200 - 1/2. The ceiling is 100' overcast and the visibility is 3/4 mile. Can you depart without a takeoff alternate?

Thanks again!
Yes

#### SpiraMirabilis

##### Possible Subversive
Actually at Mesa you would still need an T/O alternate because our derived alternate minimums with 2 nav rule would still be 400 / 1mi. 1 nav rule would be 600 / 1.5

#### Buzo

##### Well-Known Member
Actually at Mesa you would still need an T/O alternate because our derived alternate minimums with 2 nav rule would still be 400 / 1mi. 1 nav rule would be 600 / 1.5
I think you might be confusing what can be used as an alt, and when you need an alt. FAR 121.617 only requires CAT 1 landing mins. If you needed 400/1 or 600/1.5 for all your takeoffs, you would need a T/O alt alot.

#### SpiraMirabilis

##### Possible Subversive
I think you might be right!