questions about an approach

shenanigans

Pre-takeoff checklist
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I've been looking over approaches in my area and this one has me confused: http://204.108.4.16/d-tpp/1106/00915I31.PDF
There's a couple things I don't get and I'm hoping someone here can help me out.

1) When I'm using the VOR as the IAF, I fly to it and outbound on R-160 and follow the teardrop course reversal to get onto the approach course. If I'm coming from the north, that seems straightforward. But if I'm flying in from the south, do I just make a ~180 degree turn when I cross the VOR?

2) The other IAF is the AGENS intersection. So if I fly to it ... then what?

3) This procedure is "ILS RWY 31", not 'ILS or LOC RWY 31'. But it has LOC mins and times to the MAP. If the glide slope fails, you can continue the approach using localizer minimums. If that's ok, why can't you just fly it as a localizer?

4) Lastly, I notice that category D approach is NA, which I've seen elsewhere. For this approach, is it because a faster plane would overshoot the inbound course during the teardrop turn?
 
I've been looking over approaches in my area and this one has me confused: http://204.108.4.16/d-tpp/1106/00915I31.PDF
There's a couple things I don't get and I'm hoping someone here can help me out.

1) When I'm using the VOR as the IAF, I fly to it and outbound on R-160 and follow the teardrop course reversal to get onto the approach course. If I'm coming from the north, that seems straightforward. But if I'm flying in from the south, do I just make a ~180 degree turn when I cross the VOR?
Yes.

2) The other IAF is the AGENS intersection. So if I fly to it ... then what?
Good question, it does seem as if there is something left out. I would probably turn outbound on the localizer and then intercept and fly the teardrop to get turned around.

3) This procedure is "ILS RWY 31", not 'ILS or LOC RWY 31'. But it has LOC mins and times to the MAP. If the glide slope fails, you can continue the approach using localizer minimums. If that's ok, why can't you just fly it as a localizer?
You can fly the localizer only approach. The name of the procedure doesn't follow current naming conventions, but that is probably an oversight.

4) Lastly, I notice that category D approach is NA, which I've seen elsewhere. For this approach, is it because a faster plane would overshoot the inbound course during the teardrop turn?
I don't know.
 
(uploading the plate so that it doesn't disappear when the cycle changes)

2) The other IAF is the AGENS intersection. So if I fly to it ... then what?

Really, you can fly anything that you want for course reversal (as long as you stay on the protected side).

John stated one option (and a good one at that). You could also just fly it as a hold making left turns with the localizer as your inbound course. If you visualize it that way, then all of the standard hold entries start to come into play and you realize that you can execute the course reversal from any direction. Really, the only thing that you can't do is to cross AGENS and turn directly to your inbound course to intercept the localizer.
 

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2) The other IAF is the AGENS intersection. So if I fly to it ... then what?

This may be a charting mistake. The Jepp version does not list AGENS as an IAF.


Really, you can fly anything that you want for course reversal (as long as you stay on the protected side).

John stated one option (and a good one at that). You could also just fly it as a hold making left turns with the localizer as your inbound course. If you visualize it that way, then all of the standard hold entries start to come into play and you realize that you can execute the course reversal from any direction. Really, the only thing that you can't do is to cross AGENS and turn directly to your inbound course to intercept the localizer.

See the note in the profile view, "Procedure Turn NA."
 
Here's the Jepp version for comparison.

attachment.php
 

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Thanks everyone for the help. I'm trying hard to understand everything I can about approach charts.

And thanks Jason for the comparison. You're probably right about it being a mistake.
On another note, it's interesting (to me at least) that the obstacles in the center, by the river, aren't shown on the FAA chart.
 
This may be a charting mistake. The Jepp version does not list AGENS as an IAF.




See the note in the profile view, "Procedure Turn NA."

Or Jepp just doesn't list it as an IAF. I have seen several approaches where Jepp and NOAA are different in that respect..but who knows..

I have flown this approach coming from Bloomfield IA or Centerville IA many times when I flew docs around....after Agens just mimic a short portion of the outbound portion of the MA hold(dotted lines) then fly a 190-200 heading (or so) to merge onto the teardrop.
 
Dang, missed that...
You can pretty much assume that if a teardrop reversal is depicted, you can't make a normal PT or use a hold for reversal. With a teardrop reversal you are required to fly the outbound leg as shown (radial and length). The turn back won't necessarily have the same ground track as the plan view because it will vary with airspeed and wind.
 
This may be a charting mistake. The Jepp version does not list AGENS as an IAF.
I think you're right, there's no practical way to navigate to AGENS from the enroute structure so there's not much point in it being an IAF and as already noted flying the procedure from AGENS doesn't make a lot of sense. I don't know what the "INT" at AGENS is supposed to mean either. I'm also surprised that the missed approach hold radial isn't aligned with the outbound leg of the teardrop, kinda makes it messier than it needs to be if you want to try the approach again.
 
You can pretty much assume that if a teardrop reversal is depicted, you can't make a normal PT or use a hold for reversal. With a teardrop reversal you are required to fly the outbound leg as shown (radial and length). The turn back won't necessarily have the same ground track as the plan view because it will vary with airspeed and wind.

Yeah. I should have seen that. Our home field ILS is a teardrop.
 
The other thing I haven't seen mentioned yet is that the plate says "DME or RADAR required" but the all-important OTM160010 fix is not named nor marked with "RADAR" - So, is the RADAR option only for vectors to final? Is it normal to say RADAR required for vectors to final only? :dunno:
 
I don't know what the "INT" at AGENS is supposed to mean either.

"INT" = Intersection, just defining AGENS as the intersection between the OTM R-264 and I-OTM localizer course. The intersection and outer marker are co-located.

I'm also surprised that the missed approach hold radial isn't aligned with the outbound leg of the teardrop, kinda makes it messier than it needs to be if you want to try the approach again.

Agreed, not sure why that is. Specific procedure design I suppose.
 
So, is the RADAR option only for vectors to final?

I believe so.

Is it normal to say RADAR required for vectors to final only? :dunno:

Yes, but it is only noted as "RADAR REQUIRED" on IAPs as far as I am aware. For example, the ILS or LOC 31R at JFK which does not have an IAF and requires a radar vector to join the final approach course.
 
"INT" = Intersection, just defining AGENS as the intersection between the OTM R-264 and I-OTM localizer course. The intersection and outer marker are co-located.

I don't recall seeing "INT" on other charts where a named intersection exists at a marker beacon but I just checked the ILS approach at my home base and the same "INT" is there even though the OM was removed several years ago. I guess I just never noticed it before.
 
Yes, but it is only noted as "RADAR REQUIRED" on IAPs as far as I am aware. For example, the ILS or LOC 31R at JFK which does not have an IAF and requires a radar vector to join the final approach course.

I guess I meant as opposed to being RADAR required for something else - For example, the FAF on the ILS 36 into KMSN, which can be identified by DME or Radar even on a full procedure (not VTF).
 
I guess I meant as opposed to being RADAR required for something else - For example, the FAF on the ILS 36 into KMSN, which can be identified by DME or Radar even on a full procedure (not VTF).
I don't believe that you'll see "RADAR Required" on an approach just because it's needed if you want VTF. Typical reasons are a lack of feeder routes from the airways or a needed fix that can't be identified by VOR alone.
 
I don't believe that you'll see "RADAR Required" on an approach just because it's needed if you want VTF. Typical reasons are a lack of feeder routes from the airways or a needed fix that can't be identified by VOR alone.

That's what I'd have thought, but why "DME or RADAR" on this approach? You need the DME for the teardrop, but "DME *or* RADAR" would imply that Radar could be used instead of the DME fix. However, the OTM 10 DME fix on the teardrop is not marked "RADAR." :dunno:
 
Or Jepp just doesn't list it as an IAF. I have seen several approaches where Jepp and NOAA are different in that respect..but who knows..

The Jepp depiction is consistent with the definition of IAF.

I have flown this approach coming from Bloomfield IA or Centerville IA many times when I flew docs around....after Agens just mimic a short portion of the outbound portion of the MA hold(dotted lines) then fly a 190-200 heading (or so) to merge onto the teardrop.

On what clearance did you come to be at AGENS without being established on the localizer inbound?
 
The other thing I haven't seen mentioned yet is that the plate says "DME or RADAR required" but the all-important OTM160010 fix is not named nor marked with "RADAR" - So, is the RADAR option only for vectors to final?

Yes.

Is it normal to say RADAR required for vectors to final only?

Yes, when there is no other means of procedure entry. Take a look at the ILS and LOC approaches at KORD.
 
That's what I'd have thought, but why "DME or RADAR" on this approach? You need the DME for the teardrop, but "DME *or* RADAR" would imply that Radar could be used instead of the DME fix. However, the OTM 10 DME fix on the teardrop is not marked "RADAR."

I doubt the DME fix is depicted on the radar video map. There's no practical reason for it to be depicted, with radar available aircraft can just be vectored to the localizer.
 
WRT the DME or RADAR note it sounds like you can fly the full procedure with DME or get VTF with RADAR and that there's likely no way to fly the full procedure without DME (or legal GPS substitue). Seems like a note to that effect would be useful. I can see a pilot getting this approach and declining VTF only to find himself outbound with no way to identify the turning fix via radar.
 
WRT the DME or RADAR note it sounds like you can fly the full procedure with DME or get VTF with RADAR and that there's likely no way to fly the full procedure without DME (or legal GPS substitue). Seems like a note to that effect would be useful. I can see a pilot getting this approach and declining VTF only to find himself outbound with no way to identify the turning fix via radar.

I don't understand. There is a note to that effect, you referred to it in the previous sentence.
 
I don't understand. There is a note to that effect, you referred to it in the previous sentence.
I see nothing on the chart clearly indicating that flying the full approach without DME isn't going to work even when radar coverage exists.
 
I see nothing on the chart clearly indicating that flying the full approach without DME isn't going to work even when radar coverage exists.

The note says "DME or RADAR required." That doesn't clearly indicate to you that if you haven't used radar for the approach, either by choice or because radar was not available, you must use DME?
 
The note says "DME or RADAR required." That doesn't clearly indicate to you that if you haven't used radar for the approach, either by choice or because radar was not available, you must use DME?
Might be clear to you but I've "used radar" to identify fixes and given the multitude of reasons why "RADAR required" appears on approach charts I think it takes a little sleuthing to uncover the underlying cause on one like this. Yes it's possible to deduce that if you don't have DME you will need to get vectors to final but it could be more obvious.
 
Might be clear to you but I've "used radar" to identify fixes and given the multitude of reasons why "RADAR required" appears on approach charts I think it takes a little sleuthing to uncover the underlying cause on one like this.

Is that a "Yes" or a "No"?

Yes it's possible to deduce that if you don't have DME you will need to get vectors to final but it could be more obvious.

So what you're saying is either DME or radar is required to fly this approach. That's also what the note is saying, so how could it be more obvious?
 
So what you're saying is either DME or radar is required to fly this approach. That's also what the note is saying, so how could it be more obvious?

The point is, "RADAR REQUIRED" isn't normally put on a plate just for vectors to final, I don't think... For example, see the ILS 8 into CWA. It says "ADF Required" but says nothing about radar. Or the ILS 7R into KMKE. I'm sure there's a ton of others. So why would this approach say it if it's only there for VTF?
 
The point is, "RADAR REQUIRED" isn't normally put on a plate just for vectors to final, I don't think... For example, see the ILS 8 into CWA. It says "ADF Required" but says nothing about radar. Or the ILS 7R into KMKE. I'm sure there's a ton of others. So why would this approach say it if it's only there for VTF?

Don't know, but I've seen it before. Check out KOMA ILS 32R, ILS 14L, ILS 14R and ILS 18. I always assumed that it meant that there was no way to identify fixes without DME, so if you couldn't do that you'd need radar VTF. Though, I agree that it could be worded more effectively.
 
Don't know, but I've seen it before. Check out KOMA ILS 32R, ILS 14L, ILS 14R and ILS 18. I always assumed that it meant that there was no way to identify fixes without DME, so if you couldn't do that you'd need radar VTF. Though, I agree that it could be worded more effectively.

In that case, though, RADAR is good for more than VTF. For example, on the ILS 32R, you can fly a full procedure without DME but with Radar - You tell Approach you need them to call the fix for you, and when you reach BEEFF (haha) they'll let you know. You know you can do this because it says:

(IAF)
BEEFF
I-EDI |7)
RADAR

So, you could request a full procedure with approach calling BEEFF for you, fly the 305 radial off OVR until they tell you you're at BEEFF, fly outbound on the localizer, do the procedure turn, fly inbound at 2800 until they tell you you're back at BEEFF, and down you go.
 
The point is, "RADAR REQUIRED" isn't normally put on a plate just for vectors to final, I don't think...

"RADAR REQUIRED" is put on a plate just for vectors to final if there's no other means of procedure entry; see the ILS approaches into KORD for a few examples.

For example, see the ILS 8 into CWA. It says "ADF Required" but says nothing about radar.
The ILS or LOC RWY 8 into KCWA requires ADF for the missed approach procedure and procedure entry via the STE feeder route. Pilot nav procedure entry is also provided via an IAF at MAXMA on V26. It says nothing about radar because radar is not required.

Or the ILS 7R into KMKE.
The ILS or LOC RWY 7R into KMKE is a bit more complicated. ADF may be required for procedure entry via one or both feeder routes, but wouldn't be required if vectored to final. The note should be "ADF or RADAR required" or perhaps the note shouldn't be there at all.

I'm sure there's a ton of others. So why would this approach say it if it's only there for VTF?
Take a good look at the plate for the ILS RWY 31 into KOTM. Do you see any means of procedure entry that does not require either DME or radar? If your answer is no, then doesn't the note make perfect sense?
 
In that case, though, RADAR is good for more than VTF. For example, on the ILS 32R, you can fly a full procedure without DME but with Radar - You tell Approach you need them to call the fix for you, and when you reach BEEFF (haha) they'll let you know. You know you can do this because it says:

(IAF)
BEEFF
I-EDI |7)
RADAR

So, you could request a full procedure with approach calling BEEFF for you, fly the 305 radial off OVR until they tell you you're at BEEFF, fly outbound on the localizer, do the procedure turn, fly inbound at 2800 until they tell you you're back at BEEFF, and down you go.

Why would you request a full procedure with approach calling BEEFF for you? If they're able to do that they're able to provide vectors to the localizer.
 
"RADAR REQUIRED" is put on a plate just for vectors to final if there's no other means of procedure entry; see the ILS approaches into KORD for a few examples.

Yup.

The ILS or LOC RWY 8 into KCWA requires ADF for the missed approach procedure and procedure entry via the STE feeder route. Pilot nav procedure entry is also provided via an IAF at MAXMA on V26. It says nothing about radar because radar is not required.

But it could be used for vectors to final, no?

The ILS or LOC RWY 7R into KMKE is a bit more complicated. ADF may be required for procedure entry via one or both feeder routes, but wouldn't be required if vectored to final. The note should be "ADF or RADAR required" or perhaps the note shouldn't be there at all.

Well, that's why I gave it as an example - They *don't* seem to put RADAR required on if it's only for vectors to final.

Take a good look at the plate for the ILS RWY 31 into KOTM. Do you see any means of procedure entry that does not require either DME or radar? If your answer is no, then doesn't the note make perfect sense?

Finally, your twisted method of educating works... Eureka!

The only reason it mentions RADAR on that approach for vectors to final is because having RADAR (and using VTF) cancels the DME requirement... If they used a DME-only fix on the miss, for example, or if the FAF required DME and wasn't marked as a RADAR fix, this plate would simply say "DME Required" instead of "DME or RADAR Required."
 
Why would you request a full procedure with approach calling BEEFF for you? If they're able to do that they're able to provide vectors to the localizer.

Well, what's the only reason anyone requests a full procedure instead of vectors to final? Why, because there's a CFII sitting next to them, of course! :D

So, as with many other things, that was mostly a theoretical exercise. You can do it, but in real life you probably never would unless the controllers screwed up and left you REALLY high and needing to lose some altitude, in which case maybe you don't want them calling the FAF for you anyway... :yikes:
 
Yes. Your point?

That you could get VTF but it doesn't say "RADAR required." But the point is moot now that I figured out why they do list it on the OTM plate - To allow it to "cancel" the DME required note.

But they do, see the KORD examples again.

But that's a special case, where RADAR is the ONLY way to get on the approach.
 
That you could get VTF but it doesn't say "RADAR required."

It doesn't say "RADAR required" because radar is not required, the pilot can fly the approach solely on his own navigation. "RADAR required" means precisely that, you seem to be interpreting it as "RADAR available".

But that's a special case, where RADAR is the ONLY way to get on the approach.

Of course. Would you expect an approach to have the note "RADAR required" where RADAR was not the ONLY way to get on the approach?
 
Of course. Would you expect an approach to have the note "RADAR required" where RADAR was not the ONLY way to get on the approach?
RADAR REQUIRED also shows up in the plan view of the ILS32 at KSTP:

http://aeronav.faa.gov/d-tpp/1106/00263IL32.PDF

It sure looks to me like this procedure could be flown without RADAR or DME (BTW, "radar or DME" is in the notes as well).
 
RADAR REQUIRED also shows up in the plan view of the ILS32 at KSTP:

http://aeronav.faa.gov/d-tpp/1106/00263IL32.PDF

It sure looks to me like this procedure could be flown without RADAR or DME (BTW, "radar or DME" is in the notes as well).

Hmmm... That's an interesting one. I'd agree with you, but for one thing: How do you get to the approach without radar vectors?
 
Hmmm... That's an interesting one. I'd agree with you, but for one thing: How do you get to the approach without radar vectors?

I just entered the IAF into my Garmin, and it gave me a course of 047 degrees at 1386 nm.
 
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