Mins before FAF

[CA1900]

I'm skeptical that this is true.

It's a fuzzy memory at this point, but it was one of the BOS ILSs years ago. It was changed quite a while back, but I remember one of a co-worker getting chewed out for it. But it was second-hand info, and you know how that goes... My experience in Boston is that as long as you don't slow down, they're happy.

The Maximum descent gradient for an intermediate segment is 300 ft/nm, while a glideslope slopes at 3 degrees which is 318 ft/NM. If both of these conditions are met, it's impossible to a point in the intermediate segment to be above the GS. I suppose that it's possible that a lower than standard GS...

Hmm. I just looked at Boston, and all the ILSs are 3 degrees exactly. So either the glideslope was changed (unlikely), the stepdowns didn't meet the criteria you mention and were fixed (possible), or the story I got was completely bunk (most likley).

I'll dig around and see if I can find an example of one where this would bite you, but it looks like it's not the case in BOS, currently anyway. I'll keep my eyes open.

 

[SSDD]

The glideslope on the ILS25L at LAX will take you below one or two of the stepdown fixes. Its only 1 or 200 ft, but enough if a fed is in the jumpseat.

 

[rickair7777]

Thanks, you two have been very helpful

NOTE: Ceilings are a factor in some alternate requirement in 121, the details vary somewhat beween companies. So you might hear a 121 person talking about ceilings under some circumstances.

 

[Loco Gringo]

It's a fuzzy memory at this point, but it was one of the BOS ILSs years ago. It was changed quite a while back, but I remember one of a co-worker getting chewed out for it. But it was second-hand info, and you know how that goes... My experience in Boston is that as long as you don't slow down, they're happy.



Hmm. I just looked at Boston, and all the ILSs are 3 degrees exactly. So either the glideslope was changed (unlikely), the stepdowns didn't meet the criteria you mention and were fixed (possible), or the story I got was completely bunk (most likley).

I'll dig around and see if I can find an example of one where this would bite you, but it looks like it's not the case in BOS, currently anyway. I'll keep my eyes open.

KLAX Landing West, Paradise 4
www.naco.faa.gov/d-tpp/0613/00237PARADISE.PDF