MNFlyboy
Well-Known Member
Discussion topic in the pilot lounge the other day; how to determine if you legally have a half mile vis.
Discussion started during a conversation regarding 135 ops and when it's legal to shoot the approach, but also, when is it legal to land if the wx goes lower than 200 & 1/2 during an ILS. You have to have you're flight visibility so the question was, "How do you know if you have you're 1/2 mile visibility or not?"
At 200' on the ILS, and you have the approach lighting system, you can descend to 100' below the DA, and then if you pickup the runway environment, great, but how do you determine your half mile?
The best answer that I came up with was that on a 3 degree glide slope, at approx 140' agl, you are about 1/2 mile away from the thousand foot boxes on the runway, so if you can see them, you've got your half mile. But is there some other way to use the MALSR/other ALS to determine your 2650' visibility? It would seem that if you're on the ILS at 100' and all you can see is the runway #'s, that's not good enough to land? I know we might be thinking "Hell, if I can see the tarmac, I'm putting it down!" The question is, though, is that legal under 135/121?
This came up on an interview, too, so I thought this might be good discussion here.
Thanks for your participation in advance!
Discussion started during a conversation regarding 135 ops and when it's legal to shoot the approach, but also, when is it legal to land if the wx goes lower than 200 & 1/2 during an ILS. You have to have you're flight visibility so the question was, "How do you know if you have you're 1/2 mile visibility or not?"
At 200' on the ILS, and you have the approach lighting system, you can descend to 100' below the DA, and then if you pickup the runway environment, great, but how do you determine your half mile?
The best answer that I came up with was that on a 3 degree glide slope, at approx 140' agl, you are about 1/2 mile away from the thousand foot boxes on the runway, so if you can see them, you've got your half mile. But is there some other way to use the MALSR/other ALS to determine your 2650' visibility? It would seem that if you're on the ILS at 100' and all you can see is the runway #'s, that's not good enough to land? I know we might be thinking "Hell, if I can see the tarmac, I'm putting it down!" The question is, though, is that legal under 135/121?
This came up on an interview, too, so I thought this might be good discussion here.
Thanks for your participation in advance!