Can ATC Instruct, "Cross IAF, AOB on ILS" ?

westwind driver

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Here is the situation,

Final is busy, and due to merging of the streams, has to have aircraft join the LOC, then Descend maintain 5k before clearing for the approach.

Several times I have heard the instruction given, "10 miles from ABC (FAF), Cross XYZ (IAF) At or Above 5000, cleared ILS Runway XX Approach."

I thought ATC couldn't clear you for an ILS above the glideslope?

Someone please clarify this for me. I can't find anything in the 7110.65 as far as phraseology goes.
 

mynameisjim

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They can do it because you don't have to join the glideslope at that point. You could dive to the next altitude and catch the GS from there.
 

avbug

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I thought ATC couldn't clear you for an ILS above the glideslope?
You may be getting confused with being vectored, and being cleared.

Of course one can be cleared for an approach when one is above the published GSIA. One may need to fly an arc or course reversal as part of the procedure, always above the GSIA, and one is still cleared for the procedure at that point.
 

westwind driver

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You may be getting confused with being vectored, and being cleared.

Of course one can be cleared for an approach when one is above the published GSIA. One may need to fly an arc or course reversal as part of the procedure, always above the GSIA, and one is still cleared for the procedure at that point.
Actually this is being vectored onto the localiser. This happens to us shooting ILS PRM at a large domestic airport.
 

avbug

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Correct....you're being vectored, but may not be on the approach yet when you receive your clearance. Your clearance becomes effective when you're on the approach. This is very common. It's very rare that I ever hear a controller wait until I'm actually on the approach to clear me for the approach.

The controller issues the clearance before you do something. You're not already at FL310 when you're cleared to climb and maintain FL310. You're not actually on the approach when the controller says "Turn left heading 310, 3 miles from SNOWL, Cleared the ILS 30C." You haven't actually landed when you're told "cleared to land." It should come as no surprise then that you're issued a clearance while being vectored.
 

b707guy

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It's very rare that I ever hear a controller wait until I'm actually on the approach to clear me for the approach.
It happens quite frequently to receive a clearance to "fly such and such heading, intercept the localizer" without receiving approach clearance, and eventually receive the actual approach clearance well after established on the localizer, many times from a higher altitude. Sometimes, I would imagine, the controller has either forgotten to issue the clearance, or some other event precluded it's issuance. Either way, if I'm getting anywhere near the FAF or GS, I'll always ask in those cases to confirm approach clearance.

Not sure I understand westwind's situation correctly: the IAF altitude is frequently higher than the FAF/GS intercept altitude. You can be instructed to stay at, say, 5000', but you have to be cleared for the approach to descend below 5000' in this case, and, if cleared the approach, you don't have to wait until the published fix (a bit of a misnomer for a pure ILS without a marker or crossing radial to locate the "fix") to follow the glide slope.

You may be thinking of non-precision approaches regarding the requirement to be at FAF altitude, whether it's through controller clearance for by a cleared approach profile. For ILS, though, (and I'm sure there are a few exceptions out there...), you can generally be vectored to intercept the glide slope from any altitude at or above either the published intercept and then descend via the glide slope, assuming you've gotten the approach clearance.
 

Goffer

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"Turn left heading 310, 3 miles from SNOWL, Cleared the ILS 30C."
Have you been flying around KIWA lately? I just got my commercial multi add-on this week in the area.
 

Toobdrvr

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"Cleared for the approach" is an authorization to fly the routes and altitudes as published. It can be issued any time the aircraft is in a position to fly the approach as published (ie on an airway which leads to an IAF). Glideslope has nothing to do with it. You may be confused with the policy that ATC is not supposed to make you intercept the GS from above. Sorry I can't provide the chapter and verse. Hope this helps.
 

b707guy

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All I want to know is where are u flying a 707 and how can I? Really I'm serious. I have about 8000 hrs, and love 707s.
Well, I wish I could help you, since if I could, it'd mean I was still flying them myself. Haven't had the pleasure since 1996. And I do miss them!
 

westwind driver

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From FAA Order 7110.65, Chapter 5, Section 9. (Radar Arrivals) Subsection 1, part b.
(http://www.faa.gov/documentLibrary/media/Order/ATC.pdf)

"...5-9-1. VECTORS TO FINAL APPROACH COURSE

Except as provided in para 7-4-2, Vectors for Visual
Approach, vector arriving aircraft to intercept the
final approach course:...

b. For a precision approach, at an altitude not
above the glideslope/glidepath or below the
minimum glideslope intercept altitude specified on
the approach procedure chart..."

Perhaps I misread this.
 

AvroGuy

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Here is the situation,

Final is busy, and due to merging of the streams, has to have aircraft join the LOC, then Descend maintain 5k before clearing for the approach.

Several times I have heard the instruction given, "10 miles from ABC (FAF), Cross XYZ (IAF) At or Above 5000, cleared ILS Runway XX Approach."

I thought ATC couldn't clear you for an ILS above the glideslope?

Someone please clarify this for me. I can't find anything in the 7110.65 as far as phraseology goes.
this is extreamly common in ORD. ATC has started issueing such clearences. Such as 04R, they will clear you to 8000 then say maintain 8000 till DEGAN cleared ILS 04R. Now at 8000 at DEGAN puts you above the glide slope. Now you have to dive for the glide slope. Company sends out atleast 1 email a month reminding pilots to comply with the instruction. If you fly the glide slope, it puts you 200-300 below 8000 at DEGAN

IAP plate http://204.108.4.16/d-tpp/0910/00166IL4R.PDF
 

westwind driver

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Answer from A80 controller:

In the case of A80 (ATL), and when running Simultaneous Triple ILS approachs (w/PRM) the final controller has to ensure 3 miles or 1000 feet of separation between aircraft on adjacent final approach courses until BOTH are established on the LOC. This is why north final joins to 26R at 5k, center final joins to 27L at 7k or sometimes 6k, and south final joins to 28 at 4k. You hear the same thing here, "Maintain 5000 till FREAL..." The altitudes may vary at times. Due to this restriction, during IMC and heavy arrival demand, the final may wind up being 20-25 miles, as aircraft on each final approach course are vectored to intercept the LOC at around 20-25 miles to ensure the 1000' separation during the turn on to the LOC.

I thought this to very interesting.
 

b707guy

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If you fly the glide slope, it puts you 200-300 below 8000 at DEGANhttp://204.108.4.16/d-tpp/0910/00166IL4R.PDF
That used to be the case with some of the R25L/R arrivals at LAX. If you crossed CIVET on the glide slope and followed the GS all the way down, you would put yourself a few hundred feet below the minimum altitude for one or two of the many fixes on the way down. I believe that is no longer the case with any of the arrival/approach profiles there anymore. I don't know how closely the controllers watch your descent, nor do I know anyone who was violated or even called out on it, but I certainly could see a checkride bust from inside if you did that. Pretty frustrating being set up like that.
 

vtwo

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That used to be the case with some of the R25L/R arrivals at LAX. If you crossed CIVET on the glide slope and followed the GS all the way down, you would put yourself a few hundred feet below the minimum altitude for one or two of the many fixes on the way down. I believe that is no longer the case with any of the arrival/approach profiles there anymore. I don't know how closely the controllers watch your descent, nor do I know anyone who was violated or even called out on it, but I certainly could see a checkride bust from inside if you did that. Pretty frustrating being set up like that.
Lnav Vnav baby till the FAF. That is what will keep you out of trouble if you can spin, push, twist, pull fast enough.
 

tomgoodman

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Close, but not reliable

That used to be the case with some of the R25L/R arrivals at LAX. If you crossed CIVET on the glide slope and followed the GS all the way down, you would put yourself a few hundred feet below the minimum altitude for one or two of the many fixes on the way down.
Yes, that was a well-known "gotcha" approach, because sometimes it looked like the GS was going to comply with a stepdown restriction --- and at the last minute you saw that it was going to be too low. We were told that while the localizer was indeed certified for guidance a long way out, the glide slope was not.
 
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