121 wx to shoot approach prior to final fix

[Eric]

I have been told one thing and heard another. I read 121.651, and I still have questions.

Any help on the following scenarios will be appreciated. Assume this flying is done under part 121

1. Prior to final approach fix, you get atis and it reports 3/4 mile vis, ceiling 100 feet. You are going to fly an ILS. The approach requires 1/2 mile vis and has a 200' dh. Can you start the approach.

2. How about same scenario above, but the reported wx is 1/4 mile vis, ceiling 300 feet?

3. How about a non-precision approach. Plate calls for 1 mile and 500' mda. Wx reports 2 miles vis and a 300 foot ceiling?

4. Same non precision with wx reported as 1/2 mile, 700' ceiling.


I think answers to these questions will help clear up my 'visiblity is controlling' conundrum. Do you start the approach based on visibility, ceiling, or both.

Thanks

 

[vclean]

Yes, no, yes, no.

Approach visibility determines if you may continue past the FAF.

 

[falcon20driver]

Yep, visibility is the only minimum required.

 

[ThomasR]

I have been told one thing and heard another. I read 121.651, and I still have questions.

Any help on the following scenarios will be appreciated. Assume this flying is done under part 121

1. Prior to final approach fix, you get atis and it reports 3/4 mile vis, ceiling 100 feet. You are going to fly an ILS. The approach requires 1/2 mile vis and has a 200' dh. Can you start the approach.

2. How about same scenario above, but the reported wx is 1/4 mile vis, ceiling 300 feet?

3. How about a non-precision approach. Plate calls for 1 mile and 500' mda. Wx reports 2 miles vis and a 300 foot ceiling?

4. Same non precision with wx reported as 1/2 mile, 700' ceiling.

I think answers to these questions will help clear up my 'visiblity is controlling' conundrum. Do you start the approach based on visibility, ceiling, or both.

Thanks

Hope I am not confusing this too much:

1) No
2) Yes
3) No
4) No

You can bust Vis only on precision to MDA

 

[falcon20driver]

Hope I am not confusing this too much:

1) No
2) Yes
3) No
4) No

You can bust Vis only on precision to MDA

I think you got a couple of those answers bassackwards ThomasR.

#1 is Yes

#2 in No

#3 is Yes I believe, I've only flown 135 and I'm pretty sure visibility is all that is required to begin any approach, I'm going to check that one.

#4 is NO

 

[bafanguy]

Falcon20 is correct. Viz is all that controls and RVR controls ( rather than prev.viz) if that is what is reported. It gets a bit more complicated re circling approaches and receiving below mins viz report AFTER entering the final approach segment. A lot fo this stuff is spelled out in Ops Specs and FAR 121, as you mentioned.

 

[Zulu]

Here's the applicable portion (bold added):

121.651.......

(b) Except as provided in paragraph (d) of this section, no pilot may continue an approach past the final approach fix, or where a final approach fix is not used, begin the final approach segment of an instrument approach procedure—............

(2) At airports within the United States and its territories or at U.S. military airports, unless the latest weather report for that airport issued by the U.S. National Weather Service, a source approved by that Service, or a source approved by the Administrator, reports the visibility to be equal to or more than the visibility minimums prescribed for that procedure.

Notice that it says nothing about ceiling, precision vs. nonprecision, straight-in vs. circling, etc. As far as FAR 121 is concerned, ceiling in irrelevant and visibility rules for beginning an approach. Note that the company ops specs can (and probably will) be more restrictive.

So, by 121 only, my answers would be:
(1) Yes (meets visibility minimums)
(2) No (doesn't meet visibility minimums)
(3) Yes (meets visibility minimums)
(4) No (doesn't meet visibility minimums)

 

[bafanguy]

Part 121 doesn't mention a ceiling, but our Ops Specs have ceiling requirement for circling. We require "ceiling- 1000 feet or the published CatD/highest speed HAA, whichever is higher". This undoubtedly varies with companies. It can get a bit complicated when you start talking approach legalities. It's a pretty interesting subject, though.

 

[typhoonpilot]

Just as an aside, some Non-Precision approaches say " ceiling required " on them. Somebody got an example ?

TP

 

[COEX-FO]

Number 2 is No if CAT I and YES if CAT II.

COEX is now CAT II and 100/RVR1200 you are good to go!

It's fun, did it a few times to mins!