Finding a non GPS IAF into KSNS

I don't have ADF but do have DME. If I get cleared for SNS, how would I turn to go outbound? I see the procedure turn that brings me inbound but how would I turn the nearly 360 ish degrees at SNS to get me out to turn back in.
If I went to SNS, what is the purpose of the DME arc? Sorry, student pilot here, so its a little fuzzy for me
 
Coming from the south, I would expect that they could radar vector you to intercept the localizer. If not, then they could clear you via the 22 DME arc. If you are GPS equipped, the IAF for the arc should be in the procedure when selected. If no GPS, then you would fly via the SNS R-107 to intercept the arc and fly that to the localizer.

If you were coming from the north, then SNS would work, but you would fly the procedure turn to join the approach, and not the DME arc, which is intended for south arrivals.
 
Archimago said:
I don't have ADF but do have DME. If I get cleared for SNS, how would I turn to go outbound? I see the procedure turn that brings me inbound but how would I turn the nearly 360 ish degrees at SNS to get me out to turn back in.
If I went to SNS, what is the purpose of the DME arc? Sorry, student pilot here, so its a little fuzzy for me
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The turn at SNS wouldn’t be 360 ish. When you get to SNS you would turn to the right say about heading 160. That would give you about a 30 degree intercept to join the Localizer outbound. Then you do the Procedure Turn. The purpose of the DME ARC is a way to get from the IAF at what looks like the SNS 107 radial at 22 DME to the Localizer. There are no radials to follow so the DME ARC is the only way. But something is not following the logic check here. That fix, SNS107022, should coincide with the Enroute structure like you said but it does not. Disregard my comment above about getting direct UAD unless you have RNAV, the NDB has been decommissioned
 
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luvflyin said:
You could get direct UAD. If you don’t have ADF you go to SNS then the Feeder Route to UAD. You’ll need DME to do that.
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First, you have to check the NOTAMs:

!FDC 9/2569 SNS IAP SALINAS MUNI, Salinas, CA. ILS RWY 31, AMDT 5E... MSA FROM SNS VORTAC 100-220 MINIMUM ALTITUDE 6300, 220-310 MINIMUM ALTITUDE 4200, 310-100 MINIMUM ALTITUDE 5200, UAD NDB DECOMMISSIONED. DME REQUIRED. MISSED APPROACH: CLIMB TO 800 THEN CLIMBING LEFT TURN TO 4500 ON SNS R-275 TO MARNA INT/10.9 DME AND HOLD, CONTINUE CLIMB-IN-HOLD TO 4500. 1905061340-2105061339EST
 
aterpster said:
First, you have to check the NOTAMs:

!FDC 9/2569 SNS IAP SALINAS MUNI, Salinas, CA. ILS RWY 31, AMDT 5E... MSA FROM SNS VORTAC 100-220 MINIMUM ALTITUDE 6300, 220-310 MINIMUM ALTITUDE 4200, 310-100 MINIMUM ALTITUDE 5200, UAD NDB DECOMMISSIONED. DME REQUIRED. MISSED APPROACH: CLIMB TO 800 THEN CLIMBING LEFT TURN TO 4500 ON SNS R-275 TO MARNA INT/10.9 DME AND HOLD, CONTINUE CLIMB-IN-HOLD TO 4500. 1905061340-2105061339EST
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Yeah. What about that IAF 22 miles from SNS on the 107 radial? It doesn’t connect to an airway. V248 is close by on the 114 radial.
 
luvflyin said:
Yeah. What about that IAF 22 miles from SNS on the 107 radial? It doesn’t connect to an airway. V248 is close by on the 114 radial.
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What do airways have to do with it? Why does it need to coincide with the encounter structure?
 
MauleSkinner said:
What do airways have to do with it? Why does it need to coincide with the encounter structure?
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It is required by TERPs to connect to the en route structure. And, it did when the procedure was designed. It was V-137, which was recently eliminated by the MON program. The procedure should have been amended, but it wasn't. Can you make do by filing onto the SNS-107 radial? Sure, so long as that radial is not notamed as unusable. You also have to determine a 91.177 off-route MEA.

Former V-137:
V137.jpg
 
MauleSkinner said:
What do airways have to do with it? Why does it need to coincide with the encounter structure?
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So you can get to it. On some approaches an IAF doesn’t, but they will have Feeder Routes that connect the IAF to the Enroute Structure. This Approach has one. SNS to UAD, 5500. Thick bold lines are the Approach itself. Thin bold lines are Feeders. Moot point here now that the NDB has been decommissioned.

EDIT: Not a moot point. UAD is a DME Fix. The Feeder Route is valid.
 
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This is the TERPs:


2-3-1. Feeder Routes. Establish non-radar feeder routes where the IAF is not part of the en route structure and where preferred over other options [for example, radar vectors, terminal arrival area (TAA)]. Limit the number of feeder routes where radar vectoring is provided on a 24-hour basis, but where practical provide at least one route per location to account for radar/communications failure. Feeder routes originate at a navigation facility or named fix on an airway and terminate at another feeder fix or at an IAF. The feeder route must not extend beyond the operational service volume of the facility which provides navigational guidance.
 
aterpster said:
It is required by TERPs to connect to the en route structure. And, it did when the procedure was designed. It was V-137, which was recently eliminated by the MON program. The procedure should have been amended, but it wasn't. Can you make do by filing onto the SNS-107 radial? Sure, so long as that radial is not notamed as unusable. You also have to determine a 91.177 off-route MEA.

Former V-137:
View attachment 92437
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Ah Ha, an old airway. I was wondering if it was some kind of declination issue. Like V248 was the 107 radial many moons ago.
 
MauleSkinner said:
What do airways have to do with it? Why does it need to coincide with the encounter structure?
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Same thing, different way:

That's the whole idea. Despite the ability to go direct with GPS, design standards require the ability to navigate by oneself from the airway structure to the an initial approach fix. I've learned through the years that at least 80% (being conservative) of the "why do I have to...on this approach?" questions can be answered by looking at the approach, not as a stand-alone chart, but in the context of the enroute chart. This one is an example. Basically, when you look at this approach in context, when it comes to the IAFs (pre NOTAM). " you can't get there from here" without DME or ADF.
 
Almost as if they forgot to give that 107/22 fix a name. This ILS to BZN 00059IL12 (faa.gov) has arc IAF points KICDO and BRIGR that are not part of enroute structure as well, and I know I've used that arc segment from KICDO when coming from the north (as from Great Falls), but I don't recall how I joined the arc, maybe direct to the fix via GPS.
(Edit: notes say radar required for procedure from BRIGR)
 
Jim Carpenter said:
Almost as if they forgot to give that 107/22 fix a name. This ILS to BZN 00059IL12 (faa.gov) has arc IAF points KICDO and BRIGR that are not part of enroute structure as well, and I know I've used that arc segment from KICDO when coming from the north (as from Great Falls), but I don't recall how I joined the arc, maybe direct to the fix via GPS.
(Edit: notes say radar required for procedure from BRIGR)
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KICDO is on V365-536. BRIGR is in the middle of nowhere. The 223 radial should be a Feeder Route from BZN to BRIGR. Disregard, just saw your edit about Radar required.
 
Jim Carpenter said:
Almost as if they forgot to give that 107/22 fix a name.
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My guess is that they weren't naming DME fixes when this IAP was designed. Should they have named it during a periodic review? Beats me. Russ would know.
 
luvflyin said:
So you can get to it. On some approaches an IAF doesn’t, but they will have Feeder Routes that connect the IAF to the Enroute Structure. This Approach has one. SNS to UAD, 5500. Thick bold lines are the Approach itself. Thin bold lines are Feeders. Moot point here now that the NDB has been decommissioned.
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Why would the feeder route be moot? The depicted feeder route shows the radial and DME distance to the IAF where the NDB used to be.
 
luvflyin said:
So you can get to it. On some approaches an IAF doesn’t, but they will have Feeder Routes that connect the IAF to the Enroute Structure. This Approach has one. SNS to UAD, 5500. Thick bold lines are the Approach itself. Thin bold lines are Feeders. Moot point here now that the NDB has been decommissioned.

EDIT: Not a moot point. UAD is a DME Fix. The Feeder Route is valid.
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Ok..the way I read your previous post was that an IAF had to be part of the encounter structure, not that there had to be a route from that structure to the IAF.
 
So to recap the dme arc is left over from a time when the IAF coincided with a route (now decommissioned).
So coming from the south there is no way to find this IAF without gps. Coming from the north it would not make sense to fly out on the radial (plus it’s not indicated as a transition)to the dme arc when you could just fly the procedure turn.
Seems like the arc could be removed from he approach unless it serves some purpose I am missing here
 
Archimago said:
So to recap the dme arc is left over from a time when the IAF coincided with a route (now decommissioned).
So coming from the south there is no way to find this IAF without gps. Coming from the north it would not make sense to fly out on the radial (plus it’s not indicated as a transition)to the dme arc when you could just fly the procedure turn.
Seems like the arc could be removed from he approach unless it serves some purpose I am missing here
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Especially with a short arc like this, starting from the VOR is going to be almost as fast as doing the PT, but without as much maneuvering.
 
MauleSkinner said:
And for those who want to impress people at parties, “D” for DME ARC; “107” for the radial from SNS; “V” because it’s the 22nd letter of the alphabet and it’s a 22DME arc.
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Don't suppose the "V" could be for Victor Airway.
 
MLF needs to post a DME ARC from a different location.
 
Archimago said:
So to recap the dme arc is left over from a time when the IAF coincided with a route (now decommissioned).
So coming from the south there is no way to find this IAF without gps. Coming from the north it would not make sense to fly out on the radial (plus it’s not indicated as a transition)to the dme arc when you could just fly the procedure turn.
Seems like the arc could be removed from he approach unless it serves some purpose I am missing here
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What you're missing is lack of timely procedural maintenance by the FAA.
 
MauleSkinner said:
Not unless a 15-mile “O” stands for On the arc. ;)
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Here is an example from Mexico. Jepp names the DME ARC fix in parenthesis on the chart. The database has the same names. Many of these things work better in "less developed" countries.

LEON.jpg
 
Archimago said:
So to recap the dme arc is left over from a time when the IAF coincided with a route (now decommissioned).
So coming from the south there is no way to find this IAF without gps. Coming from the north it would not make sense to fly out on the radial (plus it’s not indicated as a transition)to the dme arc when you could just fly the procedure turn.
Seems like the arc could be removed from he approach unless it serves some purpose I am missing here
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You can absolutely navigate to the DME arc IAF without GPS. Fly that SNS R-107 radial to 22 DME.
 
dxfile said:
You can absolutely navigate to the DME arc IAF without GPS. Fly that SNS R-107 radial to 22 DME.
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I am not sure but I thought you could not navigate along radials that are used to identify fixes unless they indicate a minimum ifr altitude and distance—transition routes for example
 
Archimago said:
I am not sure but I thought you could not navigate along radials that are used to identify fixes unless they indicate a minimum ifr altitude and distance—transition routes for example
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True, but a controller could have you intercept the radial, then clear you via the arc for the approach. Also the controller would have you on a minimum vectoring altitude for this, until established on the arc.
 
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