“GPS required for TAA”

Llewtrah381

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For the ILS/LOC18 at KOLV, what does “GPS required for TAA” mean and how would it affect me, if at all, if I wanted to do a “standard” ILS approach? The MSA, mins for the TAA segments, and mins at EFPUB are all 2500.

https://aeronav.faa.gov/d-tpp/2202/05883IL18.PDF
 
Exactly what it means. If you want to initiate the approach utilizing the TAA, you'll need an IFR-certified GPS to do it. Otherwise you'll need to start at the IAF, EFPUB, and possibly fly a HILOPT, or receive radar vectors from Memphis.
 
I thought the purpose of the TAA was to get to the IAF? That it’s a direct route from whatever direction you’re approaching from to the IAF. In this case it’s a gps waypoint and so you need gps to go direct.

If you have gps, you can go straight there, otherwise you have to go a particular route.
 
Exactly what it means. If you want to initiate the approach utilizing the TAA, you'll need an IFR-certified GPS to do it. Otherwise you'll need to start at the IAF, EFPUB, and possibly fly a HILOPT, or receive radar vectors from Memphis.
Without GPS you’d have to start at HLI. That’s the only Feeder. EFPUB is not a connection to the Enroute Structure. Radar of course works fine also.
 
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For the ILS/LOC18 at KOLV, what does “GPS required for TAA” mean and how would it affect me, if at all, if I wanted to do a “standard” ILS approach? The MSA, mins for the TAA segments, and mins at EFPUB are all 2500.

https://aeronav.faa.gov/d-tpp/2202/05883IL18.PDF
MSA has nothing to do with ‘procedure.’ There might have been obstructions between 25 and 30 miles that may have made TAA altitudes higher than 2500.
 
Without GPS you’d have to start at HLI. That’s the only Feeder. EFPUB is not a connection to the Enroute Structure. Radar of course works fine also.
Exactly. The only two ways to get to EPUB via own nav are (1) via the HUA 136 Radial and (2) direct via one of the two TAAs. If you take the direct route, you need GPS.

BTW...
MSA has nothing to do with ‘procedure.’ There might have been obstructions between 25 and 30 miles that may have made TAA altitudes higher than 2500.
I've heard some refer to the minimum procedure altitude with a TAA as a Minimum Sector Altitude, also using "MSA." I guess we're running out of acronyms :D but I suppose it's because on an RNAV chart they (generally) replace MSAs.
 
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Is there a reason they don't have a feeder route from MEM?
 
I've heard some refer to the minimum procedure altitude with a TAA as a Minimum Sector Altitude, also using "MSA." I guess we're running out of acronyms :D but I suppose it's because on an RNAV chart they (generally) replace TAAs.
The FAA calls them areas. In this case there is a straight-in area and a course-reversal area. TAA's lost much of their value when the T legs were greatly reduced by a policy change on minimum T leg length. This particular one is of questionable value.
 
Exactly what it means. If you want to initiate the approach utilizing the TAA, you'll need an IFR-certified GPS to do it. Otherwise you'll need to start at the IAF, EFPUB, and possibly fly a HILOPT, or receive radar vectors from Memphis.
Or start at HLI VOR Feeder Fix.
 
Having a up to an 89°intercept of LOC at EFPUB would be fun.
 
Good question. MEM VOR is not on an airway.
Makes sense. It's times like these when I realize that after flying with GPS for so long, I forget some of the regulatory restrictions on the equipment code formerly known as /A. For example, from the charts, it's clear that KAWM -D> MEM -D> EFPUB -> ILS 18 KOLV could be flown safely at 2500' with /A, but I suppose that doesn't mean it can be done legally. (Aside from the fact that the good folks at KMEM would presumably never want someone doing that in their airspace.)
 
So, then, is saying "GPS required" redundant, since one is required to use a TAA?
 
Makes sense. It's times like these when I realize that after flying with GPS for so long, I forget some of the regulatory restrictions on the equipment code formerly known as /A. For example, from the charts, it's clear that KAWM -D> MEM -D> EFPUB -> ILS 18 KOLV could be flown safely at 2500' with /A, but I suppose that doesn't mean it can be done legally. (Aside from the fact that the good folks at KMEM would presumably never want someone doing that in their airspace.)
I'm no expert, but my take is that since KAWM and EFPUB are both within the service volume of MEM VORTAC, you have "navigation equipment suitable for the route to be flown" as required in 9.205(d)(2). If you were cleared on that route, I presume that ATC would have to specify an altitude. My understanding is that they will not clear you on an unpublished route unless you are in RADAR contact. Whether they would actually do so if all those conditions were met, I have no idea, but if they did, I don't see anything illegal about it. You wouldn't be using the TAA to determine course and altitude, so it looks to me like the TAA note would not be applicable.
 
Right now the HLI vortac is out of service. It's radar vectors or GPS without HLI.
 
So, then, is saying "GPS required" redundant, since one is required to use a TAA?
Maybe. But in a sense so is any equipment requirement on an approach chart. One can certainly look at a VOR or LOC chart and notice that every stepdown and the MAP are defined by DME distance with no other way to identify them and realize that DME is required. But we don't and we especially don't when selecting an approach in the middle of a flight. So approach design adds the note. All one needs to do is read a few approach chart questions with the usual number of incorrect answers to understand why things like this are made explicit.
 
I'm no expert, but my take is that since KAWM and EFPUB are both within the service volume of MEM VORTAC, you have "navigation equipment suitable for the route to be flown" as required in 9.205(d)(2). If you were cleared on that route, I presume that ATC would have to specify an altitude. My understanding is that they will not clear you on an unpublished route unless you are in RADAR contact. Whether they would actually do so if all those conditions were met, I have no idea, but if they did, I don't see anything illegal about it. You wouldn't be using the TAA to determine course and altitude, so it looks to me like the TAA note would not be applicable.
I wouldn’t say the TAA Note is not applicable. Without GPS, you simply wouldn’t be able to use the TAA. For that reason I’d say the Note is unnecessary, because it is by default, applicable, so to speak. Actually, any RNAV should work, not just GPS. I think. @aterpster , @RussR , are TAA’s limited to use by GPS? Or are other RNAV’s ok?
 
I wouldn’t say the TAA Note is not applicable. Without GPS, you simply wouldn’t be able to use the TAA. For that reason I’d say the Note is unnecessary, because it is by default, applicable, so to speak. Actually, any RNAV should work, not just GPS. I think. @aterpster , @RussR , are TAA’s limited to use by GPS? Or are other RNAV’s ok?

The example procedure was designed before the current standard for the "notes" box took effect. In addition, currently it couldn't have been designed that way anyway, as there is a relatively recent (2017) change to the criteria that prohibits establishing TAAs on ILS procedures that have a conventional missed approach segment.

From the FAAO 8260.19I:
"A Terminal Arrival Area (TAA) must not be used on ILS/LOC procedures containing a conventional missed approach."

But to generically answer the question about "other RNAVs", to allow DME/DME/IRU RNAV to be used, a DME/DME assessment would have to have been performed. In practice, this assessment is typically not performed unless specifically requested. As a result, the current note would read "RNAV 1-GPS" in the PBN Requirements box. If the assessment was performed, the note would read "RNAV 1 - GPS OR DME/DME/IRU". Reference is FAAO 8260.19I, para 8-6-8c(2)(d).

These notes, their format and the rules regarding them have changed several times in the last several years, so it's a bit of a moving target and a lot depends on when exactly the procedure was designed, or received its last amendment.
 
From the FAAO 8260.19I:
"A Terminal Arrival Area (TAA) must not be used on ILS/LOC procedures containing a conventional missed approach."
That's a weird one. Any idea why?
 
So, then, is saying "GPS required" redundant, since one is required to use a TAA?
It would be on an RNAV TAA IAP. But, this is an ILS IAP, which typically doesn't require GPS.
 
That's a weird one. Any idea why?

No idea.

And add another question to that. I'm assuming it would it would be the same for Approaches with any RNAV initial/intermediate Segments. TAA or straight line Fix to Fix.

You mean the bit about the DME/DME assessment being required? Yes, that is the same answer.
 
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