Vectors To Final When No FAF

[Dazzler]

I should know the answer to this but I guess my memory needs refreshing...

Consider a VOR instrument approach where there is no Maltese Cross depicted on the profile view of the approach chart. This indicates that the Final Approach Fix is the procedure turn inbound and consequently indicates when further descent may be made.

Now would I be correct in saying that vectors to final on these kind of approaches would not be authorized because you wouldn't know when to start a descent? (and therefore only the full procedure could be made)

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[GaTechKid]

If the VOR is located on the airfield, couldn't ATC vector you to intercept the final approach course inbound within 10 NM of the airport? They could clear you to descend to the MSA and then once established on course you could descend to MDA, the MAP designated by station passage.

Just a stab at answering your question.

[DE727UPS]

This is sort of an age old question for me that has never been answered. 10 years ago, ATC used to run us onto the final at PAE (VOR B) and say "cleared for the approach, contact the tower". Never thought it was legal or proper but let it ride as we were in a training environment and had more important things to worry about.

[RiddlePilot]

This isn't a definitive answer, but here's my thoughts:

Since instrument approaches have a "remain within" distance (usually 10nm), you can use that distance as a reference to begin your descent to segment altitude (usually MDA). As long as you have positive course guidance and are within 10 DME (or whatever specified on the chart), you should be able to safely descend.

Pretty much what GaTechKid said.

[Icelandair]

We've got an on the field VOR in Grand Forks and that is how we do it here. Within 10, down to the MDA. Because anything within 10 is inside the protected airspace if you are on a published portion.

[flyover]

[ QUOTE ]
We've got an on the field VOR in Grand Forks and that is how we do it here. Within 10, down to the MDA. Because anything within 10 is inside the protected airspace if you are on a published portion.

[/ QUOTE ]

That's the way I've been taught and always done it. Within 10 and on course, you're good. Of course figuring a VDP and then a comfortable 3 degree descent point down to it. , rather than "diving and driving" is more the norm for airline operations now.

[Dazzler]

Thanks for the responses.

I figured that the "within 10NM" answer would be given, although this assumes you have DME (or GPS) on board.

Without any other means to determine where 10NM from the VOR is (e.g. a cross radial from another VOR), I would say you would be out of options other than performing a full procedure.

[flyover]

[ QUOTE ]
Thanks for the responses.

I figured that the "within 10NM" answer would be given, although this assumes you have DME (or GPS) on board.

Without any other means to determine where 10NM from the VOR is (e.g. a cross radial from another VOR), I would say you would be out of options other than performing a full procedure.

[/ QUOTE ]

Agree completely.

[aviategw]

I'm leery of simply saying within 10nm. I dont' think you can overemphasize that you must be on a published segment of the approach. Otherwise, the MDA doesn't guaranteed you anything.

[MikeD]

[ QUOTE ]
[ QUOTE ]
We've got an on the field VOR in Grand Forks and that is how we do it here. Within 10, down to the MDA. Because anything within 10 is inside the protected airspace if you are on a published portion.

[/ QUOTE ]

That's the way I've been taught and always done it. Within 10 and on course, you're good. Of course figuring a VDP and then a comfortable 3 degree descent point down to it. , rather than "diving and driving" is more the norm for airline operations now.

[/ QUOTE ]

Agree. That's the correct procedure for approaches that have no FAF and have the MAP at the navaid, commonly known as a terminal approach.

[MidlifeFlyer]

[ QUOTE ]
I'm leery of simply saying within 10nm. I don't' think you can overemphasize that you must be on a published segment of the approach. Otherwise, the MDA doesn't guaranteed you anything.

[/ QUOTE ]You are correct. But if the approach has the standard 10 NM requirement, when you are on the FAC within 10 NM of the navaid, you =are= on an approach segment.

Aside from this, remember that vectoring places some burden on the controllers. We really need to hear from someone in ATC, but I suspect that their procedures involve either vectoring you to a point from which you may descend to the MDA or not clearing you for the approach until you may descend. That's only a guess.

[MidlifeFlyer]

I did a bit of extra inquiry on this. The ATC procedures I "suspected" don't really exist, at least not officially. The ATC Handbook talks about vectors to final solely in terms of approach gates which are imaginary point outside an FAFG. No FAF, no approach gate.

So there really isn't any official ATC procedure for vectors to final in this situation, yet we know they are given. The answer, as other pointed out, is a nav set up that allows you to know when you are inside the 10 NM. Or, you can ask ATC to let you know.

[DrBenny]

[ QUOTE ]
This is sort of an age old question for me that has never been answered. 10 years ago, ATC used to run us onto the final at PAE (VOR B) and say "cleared for the approach, contact the tower". Never thought it was legal or proper but let it ride as we were in a training environment and had more important things to worry about.

[/ QUOTE ]

What are you talking about here. Do you mean you would then execute the straight-in? For an approach where the VOR is on field, and there is no FAF, if ATC clears you for the approach shouldn't you have to fly the full approach including PT?

[DrBenny]

Wait a minute, that's right--you have to be on a published prortion of the procedure. If you're just within 10 nm you are not on a published portion, you're only within the "remain within 10 n.m. AREA of the approach."

So, if cleared for the approach, you are to fly the entire approach including PT. Otherwise, the magic words are, "Cleared for the straight-in approach," which would mean that you should have been properly vectored.

That had better be a VOR/DME or VORTAC, or you had better be visual! (Ooops! There goes the to/from!)

[MidlifeFlyer]

[ QUOTE ]
What are you talking about here. Do you mean you would then execute the straight-in? For an approach where the VOR is on field, and there is no FAF, if ATC clears you for the approach shouldn't you have to fly the full approach including PT?

[/ QUOTE ]Yes, if ATC simply says "cleared for the approach" you have to do the full approach. But the scenario here is that ATC has already told you that they are giving you "vectors to the final approach course" (note the title of the thread) which means that the full approach with the PT may =not= be done unless ATC says so..

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91.1785(j) Limitation on procedure turns. In the case of a radar vector to a final approach course or fix, a timed approach from a holding fix, or an approach for which the procedure specifies "No PT," no pilot may make a procedure turn unless cleared to do so by ATC.
==============================

Unless you refuse the clearance and ask for the full approach (clearly an option in this case), you =have to= go straight in.

[ QUOTE ]
Wait a minute, that's right--you have to be on a published portion of the procedure. If you're just within 10 nm you are not on a published portion, you're only within the "remain within 10 n.m. AREA of the approach."

[/ QUOTE ]

On the full approach, aren't you on a "published portion" when PT inbound? The final approach segment , "that segment of an instrument approach procedure in which alignment and descent for landing are accomplished" takes place in a full approach to an on-airport facility as soon as you are established inbound, doesn't it? Isn't that when established inbound within 10 NM? Why are you =not= on a published position when vectored to the same spot?

[DrBenny]

The first part makes sense if we are assuming ATC was giving vectors to final.

[ QUOTE ]




[ QUOTE ]
Wait a minute, that's right--you have to be on a published portion of the procedure. If you're just within 10 nm you are not on a published portion, you're only within the "remain within 10 n.m. AREA of the approach."

[/ QUOTE ]

On the full approach, aren't you on a "published portion" when PT inbound? The final approach segment , "that segment of an instrument approach procedure in which alignment and descent for landing are accomplished" takes place in a full approach to an on-airport facility as soon as you are established inbound, doesn't it? Isn't that when established inbound within 10 NM? Why are you =not= on a published position when vectored to the same spot?

[/ QUOTE ]

Right, but it wasn't clear to me (because I hadn't read the replies carefully enough) that this is what was meant. What I thought was being said was as long as one was within the 10 mile bubble you didn't have to fly the full approach if only "cleared for the approach" and not the "straight in."

So actually we agree:

1) If simply cleared for the approach, you have to do the whole thing.

2) If vectors to final are provided, you are to proceed straight in. BUT in this case I would also want to hear the magic "cleared for the straight in."

I would add that in my paltry experience, for some of these approaches there is no way for ATC to vector you straight in, anyway. FDK's VOR-A comes to mind--Potomac can't even hear you when you are below 2,000, so they usually clear you for the (full) approach, freq change approved.