RNAV approaches that are circling only?

NoHeat

NoHeat

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There are plenty of VOR approaches that are named without a RWY number, for example the VOR-A approach at my home drome of KIOW. It is a circling only approach.

I don't recall seeing RNAV approaches that are similar, with no specified runway in the name of the approach, and only a circling minimum. Do such approaches exist?
 
It's less frequent because RNAV doesn't have to contend with off-field navaids.
The circling only approach usually are because something causes an overly steep final approach angle (KEKN for example has some sort of obstruction in close on the final course) the angle from there to the runway exceeds six degrees.
 
Seen a lot of them. La Guardia has one
 
Many of the circling ground based approaches are circling due to the location of the navaid in relation to the airport. RNAV circling approaches are usually due to obstructions or air traffic reasons. As such, there are significantly fewer.

chartbundle said:
So, by a 'fair number' it looks like 193 in the current database. Aspen has so many circling approaches theirs is RNAV-F
http://www.chartbundle.com/qc/kase_rnav
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Or at least several revisions of the same RNAV approach.
 
Thanks. The reason I asked is that I wondered what would become of my local VOR-A approach when the VOR is eventually shut down.

I like using that approach because the IAF has a lower altitude than for the runway-specific RNAV approaches for the same airport. I think that's due to the particularly favorable terrain and lack of obstacles between the airport and the VOR station. I wonder if there's hope they will create an RNAV-A approach to replace it?
 
Are you speaking in reference to the ground based nav approaches that are planning on being removed?
 
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flyingron said:
It's less frequent because RNAV doesn't have to contend with off-field navaids.
The circling only approach usually are because something causes an overly steep final approach angle (KEKN for example has some sort of obstruction in close on the final course) the angle from there to the runway exceeds six degrees.
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The RNAV(GPS)-C into Williamsburg-Jamestown (KJGG) is much the same -- too steep a gradient on final (optimum for straight-in is 318 ft/nm, max is 400 ft/nm). But the Blue Max sandwich on Bavarian rye at Charly's there is worth the extra effort to circle-to-land.
 
This was the topic on Jepp's webinar last night. They used Aspen as one of their examples including the missed approach that uses a ILS backcourse flown backward.

Good stuff to study well in advance ;-0

Jim
 
NoHeat said:
Thanks. The reason I asked is that I wondered what would become of my local VOR-A approach when the VOR is eventually shut down.

I like using that approach because the IAF has a lower altitude than for the runway-specific RNAV approaches for the same airport. I think that's due to the particularly favorable terrain and lack of obstacles between the airport and the VOR station. I wonder if there's hope they will create an RNAV-A approach to replace it?
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I'd doubt it. Why create another RNAV approach to get a lower initial approach fix? :dunno: What do you see as the benefit of a lower IAF (I see the FAF altitudes are the same)? Seems it's how low the DA or MAP that counts more than either and I notice that is about 200' lower on the existing two RNAV approaches than the VOR-A
 
midlifeflyer said:
I'd doubt it. Why create another RNAV approach to get a lower initial approach fix? :dunno:
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Lower descent gradient on the final segment (which is measured to the TDZE, not MDA), and that may allow lower straight-in minimums instead of higher circling-only mins if there's something in the circling maneuvering area which sticks up higher than anything in the straight-in trapezoid.
 
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NoHeat said:
Thanks. The reason I asked is that I wondered what would become of my local VOR-A approach when the VOR is eventually shut down.

I like using that approach because the IAF has a lower altitude than for the runway-specific RNAV approaches for the same airport. I think that's due to the particularly favorable terrain and lack of obstacles between the airport and the VOR station. I wonder if there's hope they will create an RNAV-A approach to replace it?
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None whatsoever, unless there's a compelling operational need for it. i doubt having an IAF that's 700 higher makes much of an operational justification, compared to the cost of designing and flight checking the new procedure.
 
Ron Levy said:
Lower descent gradient on the final segment (which is measured to the TDZE, not MDA), and that may allow lower straight-in minimums instead of higher circling-only mins if there's something in the circling maneuvering area which sticks up higher than anything in the straight-in trapezoid.
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I was looking at the actual charts being referred to not some hypothetical ones. In those the real FAF (the beginning of the final segment) is at the same altitude.
 
Ron Levy said:
Hmmm -- you're right. And the FAC is within 30 degrees of the runway. So why is it circling only? :dunno:
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Could be a lack of the required runway markings or it could be the lack of a basic NPA survey for straight-in minimums.
 
midlifeflyer said:
: What do you see as the benefit of a lower IAF ?
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Icing.

It has actually happened to me that I was safely below the freezing altitude prior to the IAF for the VOR circling approach, whereas slightly higher on an RNAV runway approach ten minutes later I took on ice. This happened when I was doing practice approaches in IMC last winter.
 
Ron Levy said:
Hmmm -- you're right. And the FAC is within 30 degrees of the runway. So why is it circling only? :dunno:
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Could it be that 134ft tower right off the end of the runway (in the recycling yard) that precludes a straight-in approach ?
 
Kanp - Annapolis, MD has a RNAV GPS circling approach. We had a approach with vertical guidance and a 440 foot minimum until they build a new Giant supermarket and the building intruded in the airspace required by the approach. I would not fly the old approach to minimum as we have a short runway ( 2500 ) with a 300 foot displayed threshold. If it's that bad they I'll go to BWI.
 
weilke said:
Could it be that 134ft tower right off the end of the runway (in the recycling yard) that precludes a straight-in approach ?
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While that might preclude precision straight-in mins, unless I misunderstand the way it's done, that would only raise the nonprecision straight-in mins, not preclude them. Wally can comment further. However, knowing the way the runway is marked (or more aptly, not marked), I suspect Wally's remark about runway markings is most likely on the money.
 
Ron Levy said:
The RNAV(GPS)-C into Williamsburg-Jamestown (KJGG) is much the same -- too steep a gradient on final (optimum for straight-in is 318 ft/nm, max is 400 ft/nm). But the Blue Max sandwich on Bavarian rye at Charly's there is worth the extra effort to circle-to-land.
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That airport requires you pay attention in VFR conditions. That cute landfill mound with the trees growing on it at the end of 13 is special. My son just got accepted to WnM so I guess I will get used to it.
 
topsail said:
That airport requires you pay attention in VFR conditions. That cute landfill mound with the trees growing on it at the end of 13 is special. My son just got accepted to WnM so I guess I will get used to it.
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Great comments. I would add Day VFR. I looked at it in Google Earth.
 
NoHeat said:
Icing.

It has actually happened to me that I was safely below the freezing altitude prior to the IAF for the VOR circling approach, whereas slightly higher on an RNAV runway approach ten minutes later I took on ice. This happened when I was doing practice approaches in IMC last winter.
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The Intermediate Segments before the FAF on all three of those approaches are within 100', 2300 or 2400. They have RADAR there and I'm not seeing anything on the charts would make for real high MVA's east and southeast that would preclude being vectored to final at those altitudes. The VOR Approach is a good old "high station, low station" approach where the IAF and FAF are the same. You have to go to the Enroute Chart to find out what the minimum IAF altitude is going to be, usually a little higher than the minimum altitude on the segment that follows it. Here it's a MOCA at 2500, all the MEA's are a little higher.
 
luvflyin said:
The Intermediate Segments before the FAF on all three of those approaches are within 100', 2300 or 2400. They have RADAR there and I'm not seeing anything on the charts would make for real high MVA's east and southeast that would preclude being vectored to final at those altitudes. The VOR Approach is a good old "high station, low station" approach where the IAF and FAF are the same. You have to go to the Enroute Chart to find out what the minimum IAF altitude is going to be, usually a little higher than the minimum altitude on the segment that follows it. Here it's a MOCA at 2500, all the MEA's are a little higher.
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MVAs are quite simple in an area like that:

CID%20MVAs_zpsdjhyohmd.jpg
 
aterpster said:
MVAs are quite simple in an area like that:

CID%20MVAs_zpsdjhyohmd.jpg
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It would probably be real close whether or not you!d expect that a vector to final on the 25 approach could be down around 2500. They would have to have isolated the 2249' tower with a 3 mile circle. 2500 would give 300' above the floor of controlled airspace to have a 2500' MVA. Getting turned on from the south side far enough outside the FAF at a reasonable intercept angle might work, but it would be close. The 30 approach should be no problem. If they decommission the VOR Approach I don't think they are going to be doomed to always having to go up to 3000 or 3300 and worry about icing. I wonder what the MVA's are there now and if they'll fine tune them if a need arises.
 
Oh. I thought you were just speculating like I was. I missed the 2500 at first look and just saw the circles. Looks like they can't fine tune it much more. How did you get It?
 
luvflyin said:
Oh. I thought you were just speculating like I was. I missed the 2500 at first look and just saw the circles. Looks like they can't fine tune it much more. How did you get It?
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I get them through my work:

Filename: cid014gmvagp.dat

Date: 04/28/2014 11:49:51 AM

RNAV Runway 25 IF BUCKA is in the middle of the 3,300 MVA area.
 
aterpster said:
I get them through my work:

Filename: cid014gmvagp.dat

Date: 04/28/2014 11:49:51 AM

RNAV Runway 25 IF BUCKA is in the middle of the 3,300 MVA area.
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What is the rule on vectors to final for RNAV approaches? Is it the same as conventional approaches, or is more space required? It looks like 2 miles outside GRAFY on a 20 degree intercept might clear the 3300 area
 
luvflyin said:
What is the rule on vectors to final for RNAV approaches? Is it the same as conventional approaches, or is more space required? It looks like 2 miles outside GRAFY on a 20 degree intercept might clear the 3300 area
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If the controllers is hep he will send them directly to the IF at a 90 degree angle, or less. In order to vector to final, the RNAV final would have to be on the video map. They seldom are. The exception is when the runway is also served by an ILS. Then they use the ILS video mapped final for the RNAV IAP.
 
aterpster said:
If the controllers is hep he will send them directly to the IF at a 90 degree angle, or less. In order to vector to final, the RNAV final would have to be on the video map. They seldom are. The exception is when the runway is also served by an ILS. Then they use the ILS video mapped final for the RNAV IAP.
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OK. Looks like the best they could hope for if they really want to stay low is use RW30, get direct ICWAR at 2500 with RADAR and straight in from there
 
Troutdale, OR (KTTD) is a circling RNAV. Possibly due to Portland International being so close to the west and similar runway alignment (East/North is high terrain). So KTTD has a 019 deg for the final approach course with circle to land either 25 or 7.
 
wishboneash said:
Troutdale, OR (KTTD) is a circling RNAV. Possibly due to Portland International being so close to the west and similar runway alignment (East/North is high terrain). So KTTD has a 019 deg for the final approach course with circle to land either 25 or 7.
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Plus, the final approach course isn't aligned within the requirements for straight-in minimums. As you say, that would interfere with KPDX. An approach from the east is problematic because of terrain and close in obstacles.
 
aterpster said:
Plus, the final approach course isn't aligned within the requirements for straight-in minimums. As you say, that would interfere with KPDX. An approach from the east is problematic because of terrain and close in obstacles.
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Even without avoiding PDX traffic an approach lined up for 7 might not get straight in minimums because of terrain in the missed approach area. That approach replaced the NDB approach from LBH. It was a nightmare for approach because a huge hole had to be built in the flow into PDX and almost never got used. The RNAV approach and it's missed both cut across the grain and shouldn't require that big a hole. I doubt it, but maybe it can be done without a hole.
 
luvflyin said:
Even without avoiding PDX traffic an approach lined up for 7 might not get straight in minimums because of terrain in the missed approach area. That approach replaced the NDB approach from LBH. It was a nightmare for approach because a huge hole had to be built in the flow into PDX and almost never got used. The RNAV approach and it's missed both cut across the grain and shouldn't require that big a hole. I doubt it, but maybe it can be done without a hole.
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The GTN 650/750 simulator still has the 07 NDB-A LNAV overlay approach. The FA course is 062 deg. I guess the missed approach dictated it to become circling with high MDAs. It also certainly would have interfered with the PDX traffic from the looks of it.
 
wishboneash said:
The GTN 650/750 simulator still has the 07 NDB-A LNAV overlay approach. The FA course is 062 deg. I guess the missed approach dictated it to become circling with high MDAs. It also certainly would have interfered with the PDX traffic from the looks of it.
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That's because it is probably an old, out of date, database.
 
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