121 regs on continuing an approach-help

[Da Vinci]

ok, you are 5 miles out from faf and wx is 100ceiling and 6000 vis. can you continue the approach. ok, now this ties in w/ the question which is more prevelant, ceiling or vis....here the answer is vis-correct? i've seen written that low ceiling before the FAF-as long as vis is ok, approach can be continued. of course after FAF approach can be continued...my confusion is diff. in vis and ceiling before the FAF. thank you to anyone who clarifies this

 

[Amish RakeFight]

Yes, you can shoot the approach.

 

[Da Vinci]

actually i don't understand rvr that well at all. 6 missing 6 ok. 555 ok too??? 66missing not ok? 5missing anything not ok? i think jeppesen has 5's ok. anyone understand this well or can direct me to a location i can study and understand this stuff? thank you kindly!

 

[Doc Holiday]

The only time ceiling matters is when you are filing an alternate. Nothing else that I can think of is predicated on ceiling (except specific takeoff mins for a runway).

From the way you asked about RVR stuff, is sounds like you are referring to takeoff minimums. For a 135/121 operator, this will be in section C of your OpSpecs. There you will find specific requirements for different RVR values. As far as I know, RVR500 takeoff operations are not approved yet, but it is being worked on. Hope this helps.

 

[Andy Neill]

Da Vinci,

The 5/5/5 or 6/6/6 rules you are talking about relate to lower than standard takeoff mins and have nothing to do with the approach. They would be covered in OPSPEC C078 if your carrier has it.

For instance, if you have 16oo RVR (can see 1600 feet down the runway at the touchdown zone) AND have anything like HIRL, RCLM, CL, or anything else constituting adequate visual reference (AVR) then you can go. (The Midfield RVR can be substituted for the touchdown RVR if that is missing/inoperative)

If you can't see that far down but have 1000 RVR on both the touchdown AND the rollout AND have CL, you can go. (The midfield can be substituted for the touchdown or the rollout RVRs if missing).

If you don't have that but do have 600 in the touchdown, midfield and rollout with CL AND RCLM, you can go. (any one of the three can be missing).

SOME operators have a 500/500/500 rule in lieu of the last.

Does that help?

 

[pilotyip]

Circling anyone?

I believe the reg reads for straight in approaches vis is limiting. Ceiling and vis are limiting on circiling approaches, or that is the I have been doing it for 40 years. No one has ever corrected me.

 

[Scrapdog]

I believe the reg reads for straight in approaches vis is limiting. Ceiling and vis are limiting on circiling approaches, or that is the I have been doing it for 40 years. No one has ever corrected me.

Yip - that's because you're an aviation God, everyone is humbled by your circling approach skills. We're all thinking "Man, if I could only do an instrument approach like Yip, then I'd surely get hired ASAP by a major airline, college degree or not."

PS Yip - flippin ya sh!t...You're a good guy, even if you are completely against people getting a higher education

 

[GravityHater]

Past (and very long) discussions of landing minima on this forum had the prevailing opinion (well this is my interpretation of the 'conclusion') that there was no such thing as a "ceiling minimum". The "723/18 200 (200-1/2)" for Cat A-D a/c on the S-ILS 31R at DFW means, as it seems to state on page A1 of each of the NOS US Terminal Procedures; the first number is the Decision Altitude (or MDA in the case of a NPA) ie 723 on the altimeter.
That doesn't mean you cannot commence the approach if the reported ceiling is say, 175' agl. The reported ceiling is immaterial.
All it means is, that when the airplane arrives on the GS to the altimeter indicating 723', if you do not have the required visibility to continue to 100'agl, you cannot continue the approach.

What does matter is the reported visibility, in this case - the "18" which refers to an RVR of 1800'. Depending on operating rules (pt 91/135/121) you may or may not proceed past the FAF if the reported vis is above the minimums on the IAP, and you may not land unless you have the minimum vis, once reaching 100'agl on the ILS.

Sorry to spell this all out in gradeschool language but I am confused about the discussion above and it helps us to comprehend one another.
I gladly accept corrections - I just want to get it right.

 

[ackattacker]

I believe the reg reads for straight in approaches vis is limiting. Ceiling and vis are limiting on circiling approaches, or that is the I have been doing it for 40 years. No one has ever corrected me.

I think you've got it right. The place to look is the ops specs, not the regs. My company's ops specs require a specific reported ceiling for circling.

 

[GravityHater]

is everyone too busy with the comair thread to stop by and add some corrections?!