Feeder route question

No objection to monitoring the localizer outbound. No objection to even using the localizer to "cheat" the outbound VOR route to stay to the right of the localizer before reaching WEBVE so as not to complicate the HILPT course reversal. But flying the localizer outbound is not an approved routing. Again, here, it likely makes little practical difference because of the small angular difference. But pull up another approach plate at another airport with a larger angular displacement between the feeder route to the HILPT and the localizer back course and then...at what displacement does tracking the localizer outbound become unacceptable? With only one VOR, you will have your hands full for sure. With GPS the route to WEBVE is easy-peasy.

It would become ‘unacceptable’ when the CDI Needle deflects to the point where it would unacceptable if you were just flying that and not using the Localizer to assist you. Yeah, doing it single VOR would add some tasks and workload. Not that bad though with FlipFlop Navs. You don’t have to change the OBS every time you switch. Just leave it on 338. The LOC don’t care what the OBS says. It’d be prudent though to set it to 163 when getting ready to intercept inbound.
 
No objection to monitoring the localizer outbound. No objection to even using the localizer to "cheat" the outbound VOR route to stay to the right of the localizer before reaching WEBVE so as not to complicate the HILPT course reversal. But flying the localizer outbound is not an approved routing. Again, here, it likely makes little practical difference because of the small angular difference. But pull up another approach plate at another airport with a larger angular displacement between the feeder route to the HILPT and the localizer back course and then...at what displacement does tracking the localizer outbound become unacceptable? With only one VOR, you will have your hands full for sure. With GPS the route to WEBVE is easy-peasy.
Does anyone have an example of such an approach plate?
 
If your VOR receiver were off by six degrees, you would miss the holding fix by 1.4 NM. Would that be a problem?

Nah. You’d be able make adjustments during holding pattern entry to get it done.
 
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LOC-D at Gillespie Field KSEE. I wouldn’t go ‘hunting’ for the Localizer. But I would not let the MZB 076r take me North of it.
That one's far enough off that I don't see why anyone would be tempted to leave the VOR course.
 
LOC-D at Gillespie Field KSEE. I wouldn’t go ‘hunting’ for the Localizer. But I would not let the MZB 076r take me North of it.
That looks like a fun one. Go outbound on the MZB 076R at 7300 to BARET at 27.7 DME make your right turn to a heading of 134 for the PT for 1 min then back inbound on a heading 314 and once established inbound on the final approach course drop down to 5900 untill 15.8 DME (if inside of WOPOS)
 
I would be flying the ‘depicted feeder route.’ Using navigational equipment available to me. In this case it would be two VHF Nav receivers, at least one of them with Localizer. I’m not going to turn off the one set to the PAE 338r.
And a DME (required for this approach).
 
That one's far enough off that I don't see why anyone would be tempted to leave the VOR course.

That's my point. How far "off" does the feeder route have to be from the back course to decide that tracking the localizer outbound is not an "alternative", "close enough" route to the IAF? When one goes down this road one is essentially inventing their own approach procedure criteria. The particulars of the approach don't really matter. It's making a decision that something other than the charted procedure and clearance is "OK" without having objective criteria to draw the line.
 
. It's making a decision that something other than the charted procedure and clearance is "OK" without having objective criteria to draw the line.
It's OK, as long as you use your double secret minimums.
 
Hello all, reference KPAE ILS Z 16R. For flying the full procedure starting at PAE using the feeder to WEBVE (338 degree radial and 13.9 DME) would you do this by intercepting and flying the 338 degree radial all the way to WEBVE for the course reversal or are you supposed to fly the 338 degree radial until intercepting the back course of the localizer and track that outbound until WEBVE for the course reversal? thanks much

https://flightaware.com/resources/airport/PAE/IAP/ILS+Z+OR+LOC+Z+RWY+16R/pdf
Fly the feeder route to the IAF then start the approach, works for all feeder routes. Procedure turn required unless transition or quadrant is marked NOPT
 
No objection to even using the localizer to "cheat" the outbound VOR route to stay to the right of the localizer before reaching WEBVE so as not to complicate the HILPT course reversal. But flying the localizer outbound is not an approved routing.
If the VOR in your plane is off the allowable 4°and takes you immediately across the localizer because of it—are you going to stick to your guns and follow the radial or take the localizer to WEBVE?


...at what displacement does tracking the localizer outbound become unacceptable?
When you're more than half scale off?
 
If the VOR in your plane is off the allowable 4°and takes you immediately across the localizer because of it—are you going to stick to your guns and follow the radial or take the localizer to WEBVE?

If the required VOR receiver check is done while airborne, it can be off by as much as six degrees, no?
 
If the required VOR receiver check is done while airborne, it can be off by as much as six degrees, no?
Yes, of course, but truly I have never done one that I remember nor am I aware of anyone else. VOTs and one versus the other are the usual methods. But your point is a good one. I'd have to wonder if you followed the radial six degrees east of published combined with a crossing radial six degrees north of where WEBVE ought to be—you might be waiting a while to cross the localizer so as to begin timing for the teardrop entry. That might put you too far north for protected airspace in some aircraft.
 
Yes, of course, but truly I have never done one that I remember nor am I aware of anyone else. VOTs and one versus the other are the usual methods. But your point is a good one. I'd have to wonder if you followed the radial six degrees east of published combined with a crossing radial six degrees north of where WEBVE ought to be—you might be waiting a while to cross the localizer so as to begin timing for the teardrop entry. That might put you too far north for protected airspace in some aircraft.
They use +/- 4.5 degrees for the on course radial, 3.6 for crossing radial and .5 miles or 3% of distance from station for DME to figure the ‘fix displacement area.’ How they reconcile this with the fact that airborne VOR checks can be +/- 6, I dunno, but that’s what they use. https://www.faa.gov/documentLibrary/media/Order/Order_8260.3D_vs3.pdf
Section 2-9 starting on page 2-80.
WEBVE is an Intersection and DME Fix. DME is required for the Approach.
 
They use +/- 4.5 degrees for the on course radial, 3.6 for crossing radial and .5 miles or 3% of distance from station for DME to figure the ‘fix displacement area.’ How they reconcile this with the fact that airborne VOR checks can be +/- 6, I dunno, but that’s what they use. https://www.faa.gov/documentLibrary/media/Order/Order_8260.3D_vs3.pdf
Section 2-9 starting on page 2-80.
WEBVE is an Intersection and DME Fix. DME is required for the Approach.
Don't think DME is required for WEBVE, but it's needed for JUGBA and ECEPO. Looks like you and I and maybe Palmpilot are on the same page though.
 
Don't think DME is required for WEBVE, but it's needed for JUGBA and ECEPO. Looks like you and I and maybe Palmpilot are on the same page though.

I was wondering about that. Yeah, JUGBA is the first it’s absolutely needed. I went looking for something that said if you have DME you must use it but couldn’t find anything. Just an academic discussion. It’d be pretty silly to use CVV to identify WEBVE on the PAE Feeder unless you just wanted to do it for the exercise. If you did I doubt it would be a significant difference. I don’t know Trig but @Palmpilot seems to. CVV 089r +/- 3.6 degrees at 18.3 miles, whadda ya get?
 
I don’t know Trig but @Palmpilot seems to. CVV 089r +/- 3.6 degrees at 18.3 miles, whadda ya get?
At 60 NM one degree is 1 NM, so at 20 NM it's 1/3 of 1 NM or 2000 ft. Multiplied by 6 it's up to 12,000 ft or two miles, so a tad under two miles @ 18.3.
 
At 60 NM one degree is 1 NM, so at 20 NM it's 1/3 of 1 NM or 2000 ft. Multiplied by 6 it's up to 12,000 ft or two miles, so a tad under two miles @ 18.3.
Yeah, but that's still a bit of a nonsequitor. You could probably dead recon it with the same accuracy but that's not what the procedure calls for.

The localizer isn't much better at 18 miles. And we NEVER test the localizer processing in our planes.
 
If the VOR in your plane is off the allowable 4°and takes you immediately across the localizer because of it—are you going to stick to your guns and follow the radial or take the localizer to WEBVE?


When you're more than half scale off?

Personally, I'll use my WAAS-GPS to navigate to WEBVE, but if I was using the VOR and it was 4 degrees off and put me where I shouldn't be I'd be sending my VOR off to service. Using the localizer is a cross-check, not an approved procedure for getting to the IAF. We are talking about whether or not one should choose to use the localizer back course to navigate to the IAF instead of the published feeder route. The answer to that should be pretty clear.

For the second question, you are saying that if a feeder route is within a half deflection of the localizer course, you are going to make up your own transition to the IAF by flying the back course? I choose to follow the published route the best I can.
 
At 60 NM one degree is 1 NM, so at 20 NM it's 1/3 of 1 NM or 2000 ft. Multiplied by 6 it's up to 12,000 ft or two miles, so a tad under two miles @ 18.3.

Ah, ya don’t need Trig. Starting out with 1 degree is a mile at 60 miles, I came up with a displacement of 1.0425 X 1.098. That’s using 3.6 degrees for the CVV cross radial and 4.5 degrees for the PAE on course radial. That’s what they use so , so did I.
 
I was wondering about that. Yeah, JUGBA is the first it’s absolutely needed. I went looking for something that said if you have DME you must use it but couldn’t find anything. Just an academic discussion. It’d be pretty silly to use CVV to identify WEBVE on the PAE Feeder unless you just wanted to do it for the exercise. If you did I doubt it would be a significant difference. I don’t know Trig but @Palmpilot seems to. CVV 089r +/- 3.6 degrees at 18.3 miles, whadda ya get?
I do know trig, but I used the same 1 NM per degree at 60 NM from the VOR that dtuuri did, since arithmetic is easier than trig. :)

Although the chart says DME is required, as far as I know it's not a 'must use' item for any particular fix unless you can't identify that fix without it (as appears to be the case with JUGBA and ECEPO). I would certainly use it if I had it though, since more accuracy is generally better than less. (And of course you can substitute GPS for DME if you have it.)
 
Regarding when to switch from the VOR to the localizer, wouldn't that be allowable as soon you're within half-scale deflection on both navaids, since they both lead to the same fix?
 
Speaking of VOR-accuracy issues, the nearby ILS at Port Angeles (CLM) is an interesting one for a non-RNAV aircraft. The chart doesn't say "ADF required," and the angle and distance from CVV introduce the potential for large uncertainty in the localizer intercept point. Also, which navaid do you use to get from ELWHA to YUCSU?

When I went there a few years ago, I ended up just staying below the smoke layer because of these issues.
 

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We are talking about whether or not one should choose to use the localizer back course to navigate to the IAF instead of the published feeder route. The answer to that should be pretty clear.
It is clear, alright, that the "back course" is on the opposite end of the runway. :) We're talking about the front course here, going backwards. They aren't the same thing.
 
Ah, ya don’t need Trig. Starting out with 1 degree is a mile at 60 miles, I came up with a displacement of 1.0425 X 1.098. That’s using 3.6 degrees for the CVV cross radial and 4.5 degrees for the PAE on course radial. That’s what they use so , so did I.
Then, is that in addition to the six degrees I used for an airborne checkpoint adding still yet another error mile to the perceived position?
 
Regarding when to switch from the VOR to the localizer, wouldn't that be allowable as soon you're within half-scale deflection on both navaids, since they both lead to the same fix?
The only question about that in my mind is why a DPE wouldn't think it an example of superior airmanship over dogmatically disregarding the more accurate localizer position information readily available.
 
Speaking of VOR-accuracy issues, the nearby ILS at Port Angeles (CLM) is an interesting one for a non-RNAV aircraft, because the chart doesn't say "ADF required," and the angle and distance from CVV introduce the potential for large uncertainty in the localizer intercept point. Also, which navaid do you use to get from ELWHA to YUCSU?

I think it goes something like this. There is a way to do the Approach without ADF. You have the connection to the Enroute structure with the IAF at TOU. There are other ways to Identify the FAF than with the LOM at ELHA so ADF is not required. To do the Feeders from CVV or JIGIB it is self evident you need to be able to identify the LOM at ELWHA. Your choices are ADF or GPS via authorized substitution. If you can’t and ATC springs it on you it’s your responsibility to say unable.
ELWHA to YUCSA. YUCSA is the TOU 081 radial 29.6 mile Fix. Ya gotta get the TOU 081 radial dialed in before you get there. Start out flying the 268 Bearing From ELWHA, you got 9.8 miles to get TOU tuned, ID’d and dialed in.
 
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Speaking of VOR-accuracy issues, the nearby ILS at Port Angeles (CLM) is an interesting one for a non-RNAV aircraft. The chart doesn't say "ADF required," and the angle and distance from CVV introduce the potential for large uncertainty in the localizer intercept point. Also, which navaid do you use to get from ELWHA to YUCSU?

When I went there a few years ago, I ended up just staying below the smoke layer because of these issues.
Think you got the wrong link posted.
 
The only question about that in my mind is why a DPE wouldn't think it an example of superior airmanship over dogmatically disregarding the the more accurate localizer position information readily available.

Maybe one would. Maybe another wouldn’t
 
My math? Or that I should have used 6. That’s their rules. That’s what they use to TERP the Approach. Read my post #55 again.
Well, if I understand what you're saying, you're adding the allowable transmission error for the NAVAID to the actual location. On top of that, I'm adding the allowable receiver error for an airborne checkpoint, so the two ought to be additive, no? Then of course there's the ability of the pilot to keep the needle centered on top of that... another advantage for following the localizer due to it's better sensitivity.
 
Well, if I understand what you're saying, you're adding the allowable transmission error for the NAVAID to the actual location. On top of that, I'm adding the allowable receiver error for an airborne checkpoint, so the two ought to be additive, no?

Making the argument they should use 6 because of the airborne check tolerance has merit. But adding the lesser numbers they use, 4.5 and 3.6, on top of 6 would be a little much I think
 
Think you got the wrong link posted.
:confused2:

The attachment is the plate for the ILS at Port Angeles (CLM). That's the approach I'm talking about.
 
:confused2:

The attachment is the plate for the ILS at Port Angeles (CLM). That's the approach I'm talking about.
I got it now, must have been a browser glitch. You can navigate to an IAF without ADF, so it isn't required. But if I have ADF and use it to locate the LOM, you can bet I'm flying the localizer outbound to YUCSU. I wonder what the ones saying they'd follow the VOR to WEBVE would do?
 
The fact that ELWHA is a compass locator seems to be spurious to the approach other than if you muff the intercept of the localizer coming from CVV or JIGEB badly, you can find out which side of the marker you're on.
 
I think it goes something like this. There is a way to do the Approach without ADF. You have the connection to the Enroute structure with the IAF at TOU. There are other ways to Identify the FAF than with the LOM at ELHA so ADF is not required. To do the Feeders from CVV or JIGIB it is self evident you need to be able to identify the LOM at ELWHA. Your choices are ADF or GPS via authorized substitution. If you can’t and ATC springs it on you it’s your responsibility to say unable.
ELWHA to YUCSA. YUCSA is the TOU 081 radial 29.6 mile Fix. Ya gotta get the TOU 081 radial dialed in before you get there. Start out flying the 268 Bearing From ELWHA, you got 9.8 miles to get TOU tuned, ID’d and dialed in.
The trouble with the IAF at TOU is the note that says you can't use it if you're coming to it on V4. That is currently the only victor airway that goes to TOU!

When I brought up this problem on the old AOPA forum, Ron Levy expressed the opinion that it was OK to fly the CVV feeder routes without ADF or GPS.
 
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