Where is the MAP?

brcase

En-Route
Joined
Jun 11, 2008
Messages
2,982
Location
Boise, Idaho
Display Name

Display name:
Brian
So when shooting the KBOI LOC Y 10R approach with only a VOR/LOC reciever and RADAR (No DME or Equivalent) How do you determine the Missed approach Point?

Brian
upload_2019-3-4_17-21-33.png
 
Well...it appears that approach radar service will guide you on the final approach phase and you will go missed at 3200 feet if you can't see the runway. Hope I'm correct :)

The OP specifically mentioned LOC twice, so I'm guessing he meant when you don't have a glideslope.
 
With no DME and the tower monitoring your final approach course on RADAR, they will call your position at MAP.
 
In the Notes section, it says "DME Required." And I think now you know why. ;)

I read that to mean DME was required only if circling to the north. Am I reading it wrong? It specifically says RADAR OR DME required down on the plan view.

I tend to agree with others that the Tower will call the missed approach.

When I called the tower today to “ask a controller” their response was you should probably call us before you try it. Apparently at least the controller I talked to needed to review the procedure as well.

Brian
 
I read that to mean DME was required only if circling to the north. Am I reading it wrong? It specifically says RADAR OR DME required down on the plan view.

There is no "time to fly" published, so there is no way to fix the MAP without DME or RADAR.
 
There is no "time to fly" published, so there is no way to fix the MAP without DME or RADAR.

That is really the heart of my question. Is the Tower going to call the Missed approach if using Radar?

Part of my skeptism is I have been in the tower a number of times and my understanding was that the tower had only very limited Radar capability, at least compared to Approach control. However the Approach plate was published well after the last time I was in the tower, so perhaps the tower has better equipment now, or maybe the tower, coordinates with approach control and approach control would call the missed approach. Of course practicing in VFR conditions would not be an issue, and it is extremely unlikely I would shoot the LOC approach without DME capability in IMC conditions. The only reason it is coming up is it may be advantageous to use the LOC / Radar approach to meet the requirements of an instrument checkride with the equipment available.

Brian
 
I read that to mean DME was required only if circling to the north.
What? Why do you think that? Circling is a visual maneuver, I don't why it would require DME.
 
That is really the heart of my question. Is the Tower going to call the Missed approach if using Radar?

Part of my skeptism is I have been in the tower a number of times and my understanding was that the tower had only very limited Radar capability, at least compared to Approach control. However the Approach plate was published well after the last time I was in the tower, so perhaps the tower has better equipment now, or maybe the tower, coordinates with approach control and approach control would call the missed approach. Of course practicing in VFR conditions would not be an issue, and it is extremely unlikely I would shoot the LOC approach without DME capability in IMC conditions. The only reason it is coming up is it may be advantageous to use the LOC / Radar approach to meet the requirements of an instrument checkride with the equipment available.

Brian
When approach control provides a final controller, as in an ASR/PAR, you will stay with them until landing. Tower doesn’t call the missed approach.
 
I read that to mean DME was required only if circling to the north. Am I reading it wrong? It specifically says RADAR OR DME required down on the plan view.

No, it says circling *NA* to the north. As in, you can't circle to the north at all. And there's a period after that, and then on a new line it says "DME Required."

I tend to agree with others that the Tower will call the missed approach.

Nope. The only fix on the procedure that says "RADAR" underneath it is JIMMI. That's the only fix any controller will call for you.

It's kinda confusing why it says "RADAR or DME" on the plan view, and then "DME Required" in the notes only. Radar without DME does you no good really. I suppose if you look at it as an ILS approach, requiring the glideslope to be working, and you identify the missed solely by glideslope and altitude, you could cross-check them by having the controller call JIMMI for you. Problem is, if the glideslope goes out, what do you do? I would initiate the climb and continue tracking the localizer to intercept the BOI 113 radial, I guess, but I'm not sure if that's technically allowed.

Calling @aterpster ...
 
I have flown practice PAR approaches, but they were always at military airbases..and yes, they tell you when to go missed.

They're always at military air bases because there aren't any civilian facilities with PAR equipment - Only ASR (which has no vertical component).

They won't tell you when to go missed on this one, because JIMMI is the only radar fix.
 
... Problem is, if the glideslope goes out, what do you do? I would initiate the climb and continue tracking the localizer to intercept the BOI 113 radial, I guess, but I'm not sure if that's technically allowed...

If any part of the ILS approach goes wonky Id go missed, without DME to 6k, keep tracking till you hit that radial and into the missed and onto a GPS or my alternate

Never got how some folks say theyd shoot the loc if the ils got funky
 
Never got how some folks say theyd shoot the loc if the ils got funky

That's how we were taught in the Army. Of course, we were only flying 90 knots and timed every approach. Wouldn't work on this approach because there's nothing to time and we didn't have DME.
 
That's how we were taught in the Army. Of course, we were only flying 90 knots and timed every approach. Wouldn't work on this approach because there's nothing to time and we didn't have DME.

But if you have reason to suspect any part of that approach is compromised do you really want to keep your eggs in that basket if you have a choice to shoot a different type of approach or a different airport?
 
You need dme or a suitable GPS supplement for this approach. I think this is a misprint, the plate for the ils 28 says radar AND dme required. I would not trust ATC to call my MAP on an approach.
 
You need dme or a suitable GPS supplement for this approach. I think this is a misprint, the plate for the ils 28 says radar AND dme required. I would not trust ATC to call my MAP on an approach.

Yup... Especially not one that has you pointed at terrain like this one.
 
Yup... Especially not one that has you pointed at terrain like this one.

It's funny how when you are embroiled at figuring out how to get the rating you can miss subtle realities like the one you just pointed out. But it is, or should be a good lesson for flying IFR I think, don't fly the approach unless you completely understand it and know you have the equipment and proficiency to get it done.
 
But if you have reason to suspect any part of that approach is compromised do you really want to keep your eggs in that basket if you have a choice to shoot a different type of approach or a different airport?

Remember, that was for tactical ops and we were flying helicopters with 50% reduced visibility (1/4 mi.), so there was no other approach. The object was to get on the ground in one try with no alternate. Definitely not part 91 rules...
 
It's funny how when you are embroiled at figuring out how to get the rating you can miss subtle realities like the one you just pointed out. But it is, or should be a good lesson for flying IFR I think, don't fly the approach unless you completely understand it and know you have the equipment and proficiency to get it done.

This is why it's so important to continue learning *and flying* after getting a rating. I don't think you can truly gain an appreciation for the beauty, complexity, and three-dimensional nature of things like weather and the national airspace system without going out and being in them. A dozen years ago when I was working on my instrument rating, I'd have been focused on minutae like the final approach course... Now, when I see a question like this, I'm immediately thinking through why the approach was designed the way it was, a million different what-if scenarios, etc.

I feel like that's only been helped by planning a ton of flights, some of which have remained in the realm of fantasy, and some of which I've been lucky enough to fly. My most recent approach with big rocks around was going into Jackson Hole this summer on the RNAV(GPS) Z RWY 19. It is a pseudo-curving approach with four legs prior to the FAF on different headings, a descent gradient that was pretty challenging for the Mooney to meet (since prior to the IAF you have to be at 14,000 feet), two sets of LPV minimums because the lower one has a minimum climb gradient on the missed, etc... Really a fun approach just to study, and even more fun to fly, especially when spending a week in the valley to let you appreciate all the surrounding terrain. :)

And, that's another reason I like PoA so much - Every time one of these threads pops up with someone asking a question is another chance to examine a new approach and learn from it, and see what you missed when others point it out. I feel like I'm a safer pilot thanks to learning from all of you... Some because you're right, some because you're wrong, and some because you asked a good question. ;)
 
There are two "DME required" items. One on the plan view, one in the notes box.Until the changes to the nomenclature filter through to make it consistency clearer:

“Required” on the Planview means needed to get to an IAF from the en route environment. That's the one which is DME or RADAR. It's to get to an IAF, not for the MAP.

• “Required” in the Notes box means needed for other segments of the approach, including the missed (except for the FAC). The missed is identified by DME.
 
There are two "DME required" items. One on the plan view, one in the notes box.Until the changes to the nomenclature filter through to make it consistency clearer:

“Required” on the Planview means needed to get to an IAF from the en route environment. That's the one which is DME or RADAR. It's to get to an IAF, not for the MAP.

• “Required” in the Notes box means needed for other segments of the approach, including the missed (except for the FAC). The missed is identified by DME.
And, to me, that means that you would not (contrary to some opinions in this thread) expect to get any help from radar on the missed. I read the missed approach point for the localizer as being the 1.8 DME from I-BOI, and if you do not have DME or an approved GPS to use in its place, you cannot fly this approach as a localizer.
 
And, to me, that means that you would not (contrary to some opinions in this thread) expect to get any help from radar on the missed. I read the missed approach point for the localizer as being the 1.8 DME from I-BOI, and if you do not have DME or an approved GPS to use in its place, you cannot fly this approach as a localizer.
You can't fly it as an ILS or LOC without DME. SITSE FAF requires DME. It is not a radar fix.
 
And, to me, that means that you would not (contrary to some opinions in this thread) expect to get any help from radar on the missed. I read the missed approach point for the localizer as being the 1.8 DME from I-BOI, and if you do not have DME or an approved GPS to use in its place, you cannot fly this approach as a localizer.
Well, you "might" get help depending on how low radar coverage actually goes, and, assuming radar vectors for the ILS at or below intercept altitude, one might not feel they "need" the help to begin with but that's not the issue. The issue is whether you are permitted to fly this approach without DME (or GPS substitute) and the answer is no. There is only one RADAR fix on the chart, JIMMI. The rest are all DME fixes.
 
The OP stated "when shooting the KBOI LOC Y 10R approach with only a VOR/LOC reciever", so No. Not the ILS.
You're right, I missed that. My bad.
 
I took a quick look at all of Boise's approaches. The only approach open to you under part 91 without a DME or GPS is the visual.
  • ILS or LOC RWY 28R: DME required in notes, RADAR AND DME required in plan view
  • ILS Y or LOC Y RWY 10R: this thread
  • VOR/DME or TACAN RWY 10L: MAP is the 2.2 DME and missed approach hold is JIMMI, which requires DME
  • VOR/DME or TACAN RWY 28L: MAP is the BOI VORTAC (hooray, finally something you can identify without DME) but the missed approach hold is JIMMI

Conclusion: Let's not go to Boise. It's a silly place.
 
@brcase

The VDP is the 2.8 DME and 1.8 DME is MAP for the LOC only. There is a star note in the profile view that indicates this.

It is much more clear on the Jeep chart.
58a1ff326586fab5553ec97b30e20f8a.jpg


Sent from my Pixel 2 XL using Tapatalk
 
Last edited:
What? Why do you think that? Circling is a visual maneuver, I don't why it would require DME.

Yes I totally read that part wrong. I am coming around to the Idea it is a mis-print that “Radar Or DME required” on the plan view.
 
Yes I totally read that part wrong. I am coming around to the Idea it is a mis-print that “Radar Or DME required” on the plan view.

Well, if @midlifeflyer is correct, and I have no reason to doubt him, it's not a misprint, just something I didn't know before:

There are two "DME required" items. One on the plan view, one in the notes box.Until the changes to the nomenclature filter through to make it consistency clearer:

“Required” on the Planview means needed to get to an IAF from the en route environment. That's the one which is DME or RADAR. It's to get to an IAF, not for the MAP.

• “Required” in the Notes box means needed for other segments of the approach, including the missed (except for the FAC). The missed is identified by DME.

So that means you need DME or Radar to get to the IAF, but you need DME, period, to shoot the approach.

I am really glad that this is going to be clarified, but I'm not sure how long it's going to take to get through all the approaches!
 
Well, if @midlifeflyer is correct, and I have no reason to doubt him, it's not a misprint, just something I didn't know before:

So that means you need DME or Radar to get to the IAF, but you need DME, period, to shoot the approach.

I am really glad that this is going to be clarified, but I'm not sure how long it's going to take to get through all the approaches!
If it is a error, the error is not a chart misprint. Here is the regulatory document which forms the basis for the chart.
https://www.faa.gov/aero_docs/acifp/NDBR/2017101829976901004-BOI-NDBR/ID-BOI_ILS Y OR LOC Y RWY 10R, AMDT 13.pdf
As you will see the two DME-related "required" notes are there.

The three potential locations for an equipment required note - title, plan view, and note box - and what they generally mean is discussed in the AIM section on approach charts. See AIM 5-4-5.a.3.
 
Yes I totally read that part wrong. I am coming around to the Idea it is a mis-print that “Radar Or DME required” on the plan view.
Your idea is wrong. It is not a misprint. Attached are pages 1 and 2 of the regulatory source document. Be sure to look at both pages. Also attached is the Jeppesen chart.
 

Attachments

  • BOI Source Page 1.jpg
    BOI Source Page 1.jpg
    310.6 KB · Views: 27
  • BOI Source Page 2.jpg
    BOI Source Page 2.jpg
    185.7 KB · Views: 26
  • Jepp BOI ILS or LOC Y 10R.jpg
    Jepp BOI ILS or LOC Y 10R.jpg
    269.1 KB · Views: 27
Well, if @midlifeflyer is correct, and I have no reason to doubt him, it's not a misprint, just something I didn't know before:



So that means you need DME or Radar to get to the IAF, but you need DME, period, to shoot the approach.

I am really glad that this is going to be clarified, but I'm not sure how long it's going to take to get through all the approaches!

That is the best answer I have seen. Seems a bit odd to allow a Radar fix (in lieu of DME) when the DME is going to be required anyway. But I an understand why they might, if you are using the DME for the transition. The jeppesen chart in the post below certainly clarifies that better.

Brian
 
I don't use Jepp plates, but it certainly is the clearer presentation in this case. . .
 
Where is the Missed Approach Holding Point??

Talking about being surprised by a plate.. at some point I found out there was no MAHP for RNAV approach at my home airport. Instead there is only Missed Approach Fix.

Strangely, ILS for the same runway does have MAHP.

https://aeronav.faa.gov/d-tpp/1903/06075R25R.PDF

06075R25R.PDF
 
Last edited:
Back
Top