How do I identify the MAP on the LOC RWY 33?

It's at 0.9 DME. The dashed missed approach line on FAA charts indicates the notional start of the missed approach for the "best" line of minimums, the ILS. The LOC is indicated by the 0.9 DME fix at the runway threshold.

The Jeppesen depiction for this is, IMO, better.

There is no timing table because DME is required, therefore there's no reason to time the final.
 
rookie1255 said:
Thanks. Have a follow-up question. Is there any significance to how the DME requirement is displayed?

For the ILS at KFZY it's shown in small print in the top left.
https://aeronav.faa.gov/d-tpp/1909/05518IL33.PDF

For the ILS at KROC it's in big bold letters in the plan view.
https://aeronav.faa.gov/d-tpp/1909/00351IL22.PDF

I was wondering if the difference meant anything in relation to the DME requirement or if there was a reason the requirement was shown differently.
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It looks like the FZY approach was modified more recently (Feb 2019) compared to the ROC approach (2016). The FZY approach plate has all the approach requirements collected in the briefing bar at the top, although I must admit it's hard to miss the DME or RADAR requirement on the older version chart. Looking at the chart depiction For FZY it would become obvious at some point you need DME (or IFR GPS equivalent) to ID fixes and fly the approach.
 
chemgeek said:
...Looking at the chart depiction For FZY it would become obvious at some point you need DME (or IFR GPS equivalent) to ID fixes and fly the approach.
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I think I could fly the ILS at FZY without DME, not so the the ILS at KROC. Both LOC only approaches have fixes requiring DME or Radar.
 
rookie1255 said:
Thanks. Have a follow-up question. Is there any significance to how the DME requirement is displayed?

For the ILS at KFZY it's shown in small print in the top left.
https://aeronav.faa.gov/d-tpp/1909/05518IL33.PDF

For the ILS at KROC it's in big bold letters in the plan view.
https://aeronav.faa.gov/d-tpp/1909/00351IL22.PDF

I was wondering if the difference meant anything in relation to the DME requirement or if there was a reason the requirement was shown differently.
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It’s caused by a change in the charting standard that we started seeing last year as charts are updated.

See my blog post for more:
http://cfiruss.blogspot.com/2018/05/goodbye-dme-hello-equipment.html

Also, listen to the linked episode of the Stuck Mic AvCast for more discussion on this change.
 
RussR said:
It's at 0.9 DME. The dashed missed approach line on FAA charts indicates the notional start of the missed approach for the "best" line of minimums, the ILS. The LOC is indicated by the 0.9 DME fix at the runway threshold.

The Jeppesen depiction for this is, IMO, better.

There is no timing table because DME is required, therefore there's no reason to time the final.
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Yeah. Sometimes it’s not a bad idea though to make an ad hoc timing if you want to worry about a loss of DME after you’ve started the Approach. If something requires you to begin a Missed Approach early you can climb to the Missed Approach Altitude immediately, but you must continue to the MAP before starting turns, if any. Turning early or late can cause problems with terrain and/or traffic. Usually no big deal but some Missed Approaches are pretty tightly plotted out with respect to nearby terrain. And some are where communication with ATC is not all that good until you get some altitude. So a ‘I’m going this fast and it’s that far and it’ll take about 3minutes, 3 and a half, whatever,’ is not a bad idea sometimes.
 
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Witmo said:
I think I could fly the ILS at FZY without DME, not so the the ILS at KROC. Both LOC only approaches have fixes requiring DME or Radar.
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There is no DME fix for the MAP at ROC because the DME is from the ROC VOR rather than an ILS DME. The ROC DME doesn't meet requirements for a DME MAP. Thus, the timing table for the LOC approach.
 
Thanks @aterpster -- I'm a NOOB to the approach plate world. I think I can follow them pretty well but it's helpful for me to read WHY approaches get defined they way they are.

Doing my best to NOT become a child of the magenta line doing nothing but coupled GPS flight plans and approaches.
 
aterpster said:
There is no DME fix for the MAP at ROC because the DME is from the ROC VOR rather than an ILS DME. The ROC DME doesn't meet requirements for a DME MAP. Thus, the timing table for the LOC approach.
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Is that because it is so close? If so, how far away would it need to be?
 
mcmanigle said:
Presumably the couple of approaches that require "real" DME to guide the final approach will still be named "VOR/DME"? Martin State for example: https://aeronav.faa.gov/d-tpp/1909/05222VDTZ15.PDF
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That's an interesting case, and I can't say I know how it will be handled upon amendment. A strict reading of FAAO 8260.3D, para 1-6-2a and sub-para (1) would lead it to be named "DME RWY 15", since DME is the navigation system "used to provide lateral navigation guidance" within final.

(Actually if this rule was followed it would probably be "DME OR TACAN RWY 15".)

But that would undoubtedly cause lots of confusion.

1-6-2. Straight-in Approach Procedures. Identification includes the following elements (as applicable) in the following sequence:
a. Navigation system. The first element is the navigation system [and area navigation (RNAV) sensor in some cases] used to provide lateral navigation guidance within the final approach segment.
(1) Non-RNAV. Identify the applicable ground-based system and use the applicable abbreviation, such as, ASR, PAR, NDB, VOR, TACAN, LOC, LDA, or ILS. For localizer back course (BC) procedures, identify as “LOC BC.”
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Does anybody fly this approach for non-training purposes?
 
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luvflyin said:
Is that because it is so close? If so, how far away would it need to be?
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Could be angle of offset, or perhaps loss of lock-on at the MAP and altitude. And, perhaps dual receiver requirements close-in. I don't know; some of these requirements are a moving target.
 
RussR said:
That's an interesting case, and I can't say I know how it will be handled upon amendment. A strict reading of FAAO 8260.3D, para 1-6-2a and sub-para (1) would lead it to be named "DME RWY 15", since DME is the navigation system "used to provide lateral navigation guidance" within final.

(Actually if this rule was followed it would probably be "DME OR TACAN RWY 15".)

But that would undoubtedly cause lots of confusion.



Does anybody fly this approach for non-training purposes?
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Hmm. By the letter of the law, yeah, it would be the DME Approach. or TACAN may not be correct. But VOR or TACAN required would be needed in the Equipment Required box.
 
RussR said:
That's an interesting case, and I can't say I know how it will be handled upon amendment. A strict reading of FAAO 8260.3D, para 1-6-2a and sub-para (1) would lead it to be named "DME RWY 15", since DME is the navigation system "used to provide lateral navigation guidance" within final.

(Actually if this rule was followed it would probably be "DME OR TACAN RWY 15".)

But that would undoubtedly cause lots of confusion.

Does anybody fly this approach for non-training purposes?
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I was based at Martin State for a while and flew it a couple of times, though only by request (there are also a localizer and GPS approach to runway 15, both with lower minima). Interestingly enough, my understanding is that because DME provides lateral guidance on the final approach course, this is the one situation in which GPS cannot substitute -- you need a real-life DME.

Between that DME arc final and the LDA approach, Martin State was a good place to do instrument training (not that there's anything special about an LDA, but most people don't run into them and might not recognize the acronym).
 
RussR said:
It's at 0.9 DME...
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Are you fully sure about this? I would have read this chart differently. Due to the asterisk next to the 1.7 DME fix (note that that * is labelled 'LOC Only' in the profile view), I would have used that as the MAP. It also makes more sense from a practical point of view. At 0.9 DME you are at the threshold and unable to land from 369 ft AGL. At 1.7 DME, you are right at the VDP, 0.9 mi from the threshold, and with 1 mi visibility you should see the runway environment.

Regards,
G

Edit: did some further digging and RusR's interpretation is right. It's just not practical to actually land from this MAP. It seems that the MAP is the LAST plotted DME point on a LOC/DME chart. Not very clear, FAA!

https://captainslog.aero/2013/missed-approach-points/
 
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George Mohr said:
It's just not practical to actually land from this MAP.
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Whether or not you can land from the MAP is not a consideration in where the MAP is placed. The MAP is not supposed to serve as a "last chance to land" indicator - rather, it is saying "if you have not seen the runway by this point, you must go missed approach now." Subtly different, maybe, but important.

While the default for most types of procedures is for the MAP to be placed at the runway threshold, check out any on-airport VOR (or NDB) approach - when the MAP is the VOR (or NDB) itself, it can be some distance down the runway, or even past the runway depending on where the VOR is physically located.

Random example, the SYI VOR RWY 36: https://skyvector.com/files/tpp/1909/pdf/05299V36.PDF
or the ZZV VOR RWY 22: https://skyvector.com/files/tpp/1909/pdf/00864V22.PDF

I used to flight instruct in Dayton, OH. Springfield, OH SGH used to have a VOR RWY 24 where the VOR was at the far end of the 9000 ft runway - so by the time you reached the MAP, the runway threshold was already 1.5 nm behind you! Made it fun figuring out how far to go for a procedure turn, as well, as a slower plane could go outbound for a minute and still be over the runway.
 
Thanks. I love how I can learn something new like every time I look at this stuff.
 
mcmanigle said:
I was based at Martin State for a while and flew it a couple of times, though only by request (there are also a localizer and GPS approach to runway 15, both with lower minima). Interestingly enough, my understanding is that because DME provides lateral guidance on the final approach course, this is the one situation in which GPS cannot substitute -- you need a real-life DME.

Between that DME arc final and the LDA approach, Martin State was a good place to do instrument training (not that there's anything special about an LDA, but most people don't run into them and might not recognize the acronym).
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There are LDA's out there but this is Approach is kinda rare. You don't see LDA with Glidslope often. Can't figure out why it is RADAR Required. There are no RADAR Fixes and it's not needed for Procedure entry, there are two Terminal routes connecting the Enroute structure. And why is it an LDA? Near as I can see it uses the same transmitter the Localizer for RWY 15 uses but the Glideslope is placed for RWY 33. @RussR ,what's going on here?
 
mcmanigle said:
I was based at Martin State for a while and flew it a couple of times, though only by request (there are also a localizer and GPS approach to runway 15, both with lower minima). Interestingly enough, my understanding is that because DME provides lateral guidance on the final approach course, this is the one situation in which GPS cannot substitute -- you need a real-life DME.

Between that DME arc final and the LDA approach, Martin State was a good place to do instrument training (not that there's anything special about an LDA, but most people don't run into them and might not recognize the acronym).
Click to expand...
That makes me wish I had a dme just to fly that dme arc. That’s pretty cool and looks like it will keep you on your toes.
 
luvflyin said:
There are LDA's out there but this is Approach is kinda rare. You don't see LDA with Glidslope often. Can't figure out why it is RADAR Required. There are no RADAR Fixes and it's not needed for Procedure entry, there are two Terminal routes connecting the Enroute structure. And why is it an LDA? Near as I can see it uses the same transmitter the Localizer for RWY 15 uses but the Glideslope is placed for RWY 33. @RussR ,what's going on here?
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I always assumed radar required was because of the restricted areas. I agree I don't see any navigation reason requiring it.

I believe this particular one is LDA because it doesn't have the appropriate approach lighting to be ILS. Approach lights would have to extend over the water in an area of frequent boat traffic. So although I can't see any other ILS requirements it's missing off the top of my head, I think that's what does it.

benyflyguy said:
That makes me wish I had a dme just to fly that dme arc. That’s pretty cool and looks like it will keep you on your toes.
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It's fun! Though quite non-precision (the fact that minima are the same straight in vs circling is probably a give away for that). You can certainly practice it for fun with GPS, just not officially IFR.
 
mcmanigle said:
I always assumed radar required was because of the restricted areas. I agree I don't see any navigation reason requiring it.

I believe this particular one is LDA because it doesn't have the appropriate approach lighting to be ILS. Approach lights would have to extend over the water in an area of frequent boat traffic. So although I can't see any other ILS requirements it's missing off the top of my head, I think that's what does it.



It's fun! Though quite non-precision (the fact that minima are the same straight in vs circling is probably a give away for that). You can certainly practice it for fun with GPS, just not officially IFR.
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RWY 15 doesn’t have Approach lights either. I looked up some stuff on LDA. I think the reason 33 is LDA might be because the localizer antenna is so close to the threshold instead of at the far end of the runway.
 
mcmanigle said:
I believe this particular one is LDA because it doesn't have the appropriate approach lighting to be ILS. Approach lights would have to extend over the water in an area of frequent boat traffic. So although I can't see any other ILS requirements it's missing off the top of my head, I think that's what does it.
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Approach lights aren't mandatory for an ILS. Without them it's usually 250 and 3/4. There is some other reason that this IAP is an LDA with GS.
 
luvflyin said:
There are LDA's out there but this is Approach is kinda rare. You don't see LDA with Glidslope often. Can't figure out why it is RADAR Required. There are no RADAR Fixes and it's not needed for Procedure entry, there are two Terminal routes connecting the Enroute structure. And why is it an LDA? Near as I can see it uses the same transmitter the Localizer for RWY 15 uses but the Glideslope is placed for RWY 33. @RussR ,what's going on here?
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Wouldn't it be radar required because the missed approach is partly inside class B airspace?
 
mtuomi said:
Wouldn't it be radar required because the missed approach is partly inside class B airspace?
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I'm not sure what class B airspace has to do with it. Many approaches go through class B without such a legend (and RADAR isn't required for class B penetration strictly).
 
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flyingron said:
I'm not sure what class B airspace has to do with it. Many approaches go through class B without such a legend (and RADAR isn't required for class B penetration strictly).
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In this case, an approach without a radar would close down KBWI. I'm not sure if that could be causing it.
I don't understand why this is a radar required and an LDA/GS and not a straight ILS.
 
I think there's differing obstacle clearance primary/transitional areas for LOC vs. LDA. They've got a problem because there are tall masted sailboats just off the end of the runway.
 
flyingron said:
I think there's differing obstacle clearance primary/transitional areas for LOC vs. LDA. They've got a problem because there are tall masted sailboats just off the end of the runway.
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Nope. LDA and LOC have identical criteria. My guess is that the facility does not meet flight inspection requirements for an ILS.
 
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