Failed instrument checkride today.

I was under the impression that VDPs were supposed to be marked on the chart. I don't see one on that chart.
They aren't on all charts. There are criteria for when they are charted. I just don't remember what those criteria are.

That said, you can still compute your own unofficial VDP on any straight-in approach to help your situational awareness and predetermined choices on what you might want to do depending on how far out you are when you see (or don't see) the runway environment. All you need do is figure out how much distance it will take you to descend from MDA to the runway -- which is a function of HAT and the descent angle you normally fly visually.
 
But SLI to PRADO isn't a feeder route. It's a radial to identify the fix only, in my interpretation.
 
From the AIM: Visual Descent Points (VDPs) are being incorporated in nonprecision approach procedures. The VDP is a defined point on the final approach course of a nonprecision straight-in approach procedure from which normal descent from the MDA to the runway touchdown point may be commenced, provided visual reference required by 14 CFR Section 91.175(c)(3) is established. The VDP will normally be identified by DME on VOR and LOC procedures and by along-track distance to the next waypoint for RNAV procedures. The VDP is identified on the profile view of the approach chart by the symbol: V

1. VDPs are intended to provide additional guidance where they are implemented. No special technique is required to fly a procedure with a VDP. The pilot should not descend below the MDA prior to reaching the VDP and acquiring the necessary visual reference.
2. Pilots not equipped to receive the VDP should fly the approach procedure as though no VDP had been provided.
 
But SLI to PRADO isn't a feeder route. It's a radial to identify the fix only, in my interpretation.
I've been looking for examples of feeder routes and couldn't find any. Technically you may be right, that may not be the correct term for that route. But it's still a legitimate clearance. There are several approaches in my area where absent a GPS, the only route to the IAF from the enroute structure is along a charted radial that is not specifically designated as a feeder route. In your case, the route is via PRADO instead of direct to the IAF, but it's still flyable /U.
 
Actually, if you look at the enroute chart, PRADO is part of the enroute structure -- it's at the intersection of V16-370 and V363. Likewise, SLI is part of the enroute structure and is on a couple of airways. So there is no need for a feeder route from SLI to PRADO, there's an airway route that will get you there.

I believe that PRADO to GOLDI is a bona-fide feeder route, however.
 
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I looked over the approach. It is a tough one for the transition. If you flew the V8-21 airway, you may have gotten snagged also depending on your altitude. The Seal Beach out has a 3000' section followed by a step up restrictions to 4100 and the 4000 on V363.

Truly this DPE knows how to torture...


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I've been looking for examples of feeder routes and couldn't find any.

I see two on this chart:

1. It appears to me that if you get to PRADO without flying to one of the IAFs first, then the route from PRADO to the IAF at GOLDI plays the role of a feeder route. [Correction: See posts #53 and 54.]

2. The heavy black arrow pointing south from POM is a feeder route from POM to the IAF at GOLDI.

Technically you may be right, that may not be the correct term for that route. But it's still a legitimate clearance. There are several approaches in my area where absent a GPS, the only route to the IAF from the enroute structure is along a charted radial that is not specifically designated as a feeder route. In your case, the route is via PRADO instead of direct to the IAF, but it's still flyable /U.

The radial from SLI to PRADO is not a feeder route because there's no minimum altitude shown on the radial, and it's not depicted with a heavy black line. It's more than a technicality, because in order to fly that radial, you would need an altitude specified by ATC.
 
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Actually, if you look at the enroute chart, PRADO is part of the enroute structure -- it's at the intersection of V16-370 and V363. Likewise, SLI is part of the enroute structure and is on a couple of airways. So there is no need for a feeder route from SLI to PRADO, there's an airway route that will get you there.



I believe that PRADO to GOLDI is a bona-fide feeder route, however.


You mean something like SLI POXKU PRADO? I wouldn't have thought of that. Good catch. And, good trick.

Fly it at 4000 min so you don't get caught on the transition to the approach structure.
 
I believe that PRADO to GOLDI is a bona-fide feeder route, however.

When you get there from somewhere other than the IAFs at LAHAB or PDZ, I agree. Otherwise, it's a part of the approach itself.
 
...I still am a little fuzzy on how long into a VOR, LOC or ILS approach I can have guidance from GPS. If someone could explain that for me I'd appreciate it...

In addition to what else has been said, when you're approaching PRADO from LAHAB, it would be advantageous to be ready to identify the 175 degree lead radial. One way to do that would be to have the 430 in V-LOC mode before that point, and use a separate VOR receiver to track the PDZ 256 degree radial inbound until you reach the lead radial. Of course, you would have to remember to change the OBS from 175 FROM to 344 TO at the appropriate time. I would use the same setup if I were coming in from PDZ even though there is no lead radial on that side, to reduce the amount of knob twisting and/or button pushing at PRADO.

I was coming in from the Seal Beach (SLI) VOR on the ride. The plate gives no way of getting to the IAF LAHAB coming from that direction. How do you get to it without GPS?

One way would be SLI V459 DODGR V16 LAHAB.

http://skyvector.com/?ll=33.8927614...&plan=A.K1.KCVO:A.K2.KRDD:A.K2.KOVE:A.K2.KRHV

PRADO wpt is not an Intermediate Fix (IF) at all, which we kind of had flown based on the 430 and (in my mind) assumed.

PRADO is an intermediate fix if you get there from the IAF at LAHAB or PDZ.
 
My take is that, if you're coming from SLI VOR, PRADO is a waypoint along the feeder route to the IAF GOLDI.

So if you are flying this path using VOR, are you going SLI, PRADO, GOLDI (turn somehow back to track the POM 164 radial outbound, cross GOLDI again, procedure turn, inbound on POM 344, to the airport? Seems pretty convoluted. Asking this question a slight different way, under what circumstances could you permissibly just go SLI, PRADO, GOLDI to the airport?
 
So if you are flying this path using VOR, are you going SLI, PRADO, GOLDI (turn somehow back to track the POM 164 radial outbound, cross GOLDI again, procedure turn, inbound on POM 344, to the airport? Seems pretty convoluted. Asking this question a slight different way, under what circumstances could you permissibly just go SLI, PRADO, GOLDI to the airport?

The route from PRADO says NoPT, so when you get to GOLDI the first time, you just keep going inbound toward the airport.
 
PRADO is an IF also when there is no initial approach segment and it's part of the en route structure.

dtuuri

If that's the case, then I was mistaken in saying that not using the IAF at LAHAB or PDZ makes the route from PRADO to GOLDI a transition route. I take it that the IAF at GOLDI only applies when you reach it from somewhere other than PRADO?
 
From the AIM: Visual Descent Points (VDPs) are being incorporated in nonprecision approach procedures. The VDP is a defined point on the final approach course of a nonprecision straight-in approach procedure from which normal descent from the MDA to the runway touchdown point may be commenced, provided visual reference required by 14 CFR Section 91.175(c)(3) is established. The VDP will normally be identified by DME on VOR and LOC procedures and by along-track distance to the next waypoint for RNAV procedures. The VDP is identified on the profile view of the approach chart by the symbol: V

1. VDPs are intended to provide additional guidance where they are implemented. No special technique is required to fly a procedure with a VDP. The pilot should not descend below the MDA prior to reaching the VDP and acquiring the necessary visual reference.
2. Pilots not equipped to receive the VDP should fly the approach procedure as though no VDP had been provided.

Sorry to step back, but are we all in agreement that there is no VDP on this approach?
 
The route from PRADO says NoPT, so when you get to GOLDI the first time, you just keep going inbound toward the airport.

If that is true (and I don't mean to suggest that it isn't), then this seems to be a pretty straight forward approach.
 
Like I said earlier, "Truly this DPE knows how to torture..." :)

I do believe if you are /U or /A and are doing this approach without vectors, the expectation that you use the enroute system to get to Prado, then continue on until Goldi at 2500' and complete the approach without a PT.

It is a good approach to use on a check ride. Got me thinking!


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If that is true (and I don't mean to suggest that it isn't), then this seems to be a pretty straight forward approach.

Having four different entry routes may make it seem more complex than it really is.
 
If that is true (and I don't mean to suggest that it isn't), then this seems to be a pretty straight forward approach.

So SLI PRADO GOLDI is a legitimate approach procedure here? What about altitudes? MSA looks like 7700 in the sector coming from SLI but 2500 is allowed at PRADO inbound. How/when do you lose that altitude? Dropping 5200 feet in 6.3 miles (at, say, 90kts?) is over a 1200 fpm descent (1238), if my math is right.
 
The glass panel is well on the way to being the root cause of a rising accident rate in glass equipped GA light aircraft.
You can feel bad that the complexity of the glass kept you from getting the rating.
You can feel even badder when the complexity of the glass either puts you into the Prez's no fly zone, or into the ground.
I'm suspecting that the time is coming you will have to attend a school and get a type rating for any given model of glass panel before you can fly it.

No, I don't think glass will go away.
What I know (not think) is that it is going to raise the time, cost, and increase the hoops we have to jump through just to fly.
 
When you get there from somewhere other than the IAFs at LAHAB or PDZ, I agree. Otherwise, it's a part of the approach itself.
Yes, that's what I meant. If you arrive at PRADO on V363 northbound, then it's definitely a feeder route for you.
 
PRADO is an IF also when there is no initial approach segment and it's part of the en route structure.
Do you have a reference for that? I would have thought that if you enter the approach via PRADO then GOLDI, GOLDI is both the IAF and the FAF and there is no intermediate approach segment.
 
So SLI PRADO GOLDI is a legitimate approach procedure here? What about altitudes? MSA looks like 7700 in the sector coming from SLI but 2500 is allowed at PRADO inbound. How/when do you lose that altitude? Dropping 5200 feet in 6.3 miles (at, say, 90kts?) is over a 1200 fpm descent (1238), if my math is right.

Great questions, to which I do not have solid answers. Maybe the instrument proficient pilots/CFIIs/air traffic controllers out there will jump in and set me straight. There is a difference between MSA, and minimum vectoring altitude. My educated guess, (but a guess nonetheless) is that you might be able to get the controller to clear you to a lower altitude so that you don't have so much altitude to lose.

If not, then I would guess you want to get vectors to GOLDI so that you have extra time to descend and configure. But then you are going to have to go outbound on the 164 radial, and have to do the procedure turn. In such case, at least they won't give you too steep of a turn to intercept the outbound radial.

(Disclaimer--I'm not instrument rated. Just an instrument student.)
 
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Experienced pilots having a disagreement about an approach is exactly why these need to be eliminated in favor of GPS approaches. In real life I wouldn't use that approach in anything but super high ceilings. First is isn't that good, even with DME you are at 1640 at ~90 degrees to the runways. So now you get to circle with 600' ceilings? Nope, not me.

In contrast the GPS LPV puts me at 1315 right down the pipe, 300' lower and much safer. If the winds are favoring 8 then the ceiling better be well above minimums and I would still rather come off the GPS lined up for the downwind.

If the DPE told me conditions were at minimums, we were in a /u aircraft, my real world answer would be, "I'm going to another airport".
 
VORs are being decommissioned fairly rapidly. I say fly the GPS approach and be done with it. :)
 
So SLI PRADO GOLDI is a legitimate approach procedure here? What about altitudes? MSA looks like 7700 in the sector coming from SLI but 2500 is allowed at PRADO inbound. How/when do you lose that altitude? Dropping 5200 feet in 6.3 miles (at, say, 90kts?) is over a 1200 fpm descent (1238), if my math is right.
I could be wrong about that -- but I assumed that you would only fly that route if cleared and in a radar environment. The controller's MIA along the SLI 043 might be significantly lower than the sector MSA. Certainly there has to be some point there where it's safe to descend to 4000, as that is the charted altitude on the approach chart coming from both PDZ and LAHAB, and also along V363.

It's interesting that the MEA on V16 from PDZ to PRADO is shown as 5000 on the enroute chart, yet on the approach chart, it's 4000 though the two courses are defined by the exact same radial. Any ideas why that might be?
 
Azure -- I saw that difference on V16 as well. Wonder if it is because as an enroute airway in a mountainous area it is set for the 3000' stuff south of the airway and as a IF feeder they have the latitude to set it to 1000' above.


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But PRADO can't be an Intermediate Fix as it doesn't have the letters IF next to it. I'm more confused than I ever was.
 
Great questions, to which I do not have solid answers. Maybe the instrument proficient pilots/CFIIs/air traffic controllers out there will jump in and set me straight. There is a difference between MSA, and minimum vectoring altitude. My educated guess, (but a guess nonetheless) is that you might be able to get the controller to clear you to a lower altitude so that you don't have so much altitude to lose.

If not, then I would guess you want to get vectors to GOLDI so that you have extra time to descend and configure. But then you are going to have to go outbound on the 164 radial, and have to do the procedure turn. In such case, at least they won't give you too steep of a turn to intercept the outbound radial.

(Disclaimer--I'm not instrument rated. Just an instrument student.)

Here's the problem: I *am* instrument rated. And proficient (or at least that's what the DPE told me not too long ago when he handed me my temporary cert). Truth is, I'm not sure I know how to ACTUALLY fly this approach, so hopefully I manage to learn something from this thread before it's over.

In the meantime, I don't doubt SLI PRADO GOLDI is a valid option. But based on the descent rate required it's certainly not a great one. I think I like the idea of using airways to get to LAHAB better.

So, as someone previously said, SLI V459 DODGR V16 LAHAB and then fly the approach using LAHAB as the IAF. (Something like this: http://skyvector.com/?ll=33.8888095...2&zoom=1&plan=A.K2.KSLI:F.K2.DODGR:F.K2.LAHAB) This route allows you to descent to 4000 before PRADO, making that descent a little easier to handle (dropping 1500 ft from PRADO in 6.3 miles is, at 90 kts ground speed, a descent rate of about 357 fpm).

Though I really do hope to hear from someone more seasoned and educated than I am about how this should REALLY be done in a /U or /A aircraft.
 
I could be wrong about that -- but I assumed that you would only fly that route if cleared and in a radar environment. The controller's MIA along the SLI 043 might be significantly lower than the sector MSA. Certainly there has to be some point there where it's safe to descend to 4000, as that is the charted altitude on the approach chart coming from both PDZ and LAHAB, and also along V363.

It's interesting that the MEA on V16 from PDZ to PRADO is shown as 5000 on the enroute chart, yet on the approach chart, it's 4000 though the two courses are defined by the exact same radial. Any ideas why that might be?

I have absolutely no idea. My first inclination is that one of them is incorrect. Chart errors aren't unheard of, but I'd say they're fairly unlikely. Maybe there's some leeway for the lower altitude as part of the IAP? If you're enroute your MEA is 5000; if you're on the approach you can drop lower (since PDZ is an IAF for this approach)?
 
Do you have a reference for that? I would have thought that if you enter the approach via PRADO then GOLDI, GOLDI is both the IAF and the FAF and there is no intermediate approach segment.

I have a link to TERPS on my website. Look for Volume I par 220 (320?). EDIT: par 230!

The thing is, when you plan the flight you need to to figure your MIA for any direct legs. Easier to stay on airways to PRADO (if that's where you want to go). After you're on your way, if ATC upsets your plan, then ATC will give you an altitude to maintain until established on a published route segment, "Maintain 3000 until established, procede direct PRADO, cleared for the VOR approach." Assuming you can nav via RNAV, but want the VOR approach, that is.

dtuuri
 
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I have absolutely no idea. My first inclination is that one of them is incorrect. Chart errors aren't unheard of, but I'd say they're fairly unlikely. Maybe there's some leeway for the lower altitude as part of the IAP? If you're enroute your MEA is 5000; if you're on the approach you can drop lower (since PDZ is an IAF for this approach)?
My problem is that the MEA is designed so that it meets obstacle clearance requirements as well as adequate navigation signal reception. You need both if you're flying the approach on your own nav. So why isn't the MEA 4000?

I could understand if this were a true GPS approach since the course width in terminal mode on a GPS is less than in enroute mode, and certainly less than the 8nm of an airway, and there might be terrain issues (likely, since this is a mountainous area). Maybe the reason is that you're within only a few nm (13 I believe) of the VOR on that segment so the sensitivity is high, and half scale deflection ("established" on the segment) is only a nm or two from the center of the airway, so an obstacle like that 3045 foot summit might be too close to the airway edge, but far enough away if you're established on the initial approach segment.

But I'm just guessing. I'm a pretty recent IR graduate too, I've only had my ticket for a year and a half. Lots to learn here.
 
So SLI PRADO GOLDI is a legitimate approach procedure here? What about altitudes?

No. The only way you could fly the radial from SLI to PRADO is if the controller instructed you to do so AND gave you an altitude assignment. That radial is not part of the approach procedure, because there's no thick black line, and there's no minimum altitude printed next to it.

MSA looks like 7700 in the sector coming from SLI but 2500 is allowed at PRADO inbound. How/when do you lose that altitude? Dropping 5200 feet in 6.3 miles (at, say, 90kts?) is over a 1200 fpm descent (1238), if my math is right.

See the first sentence of AIM 5-4-5e. The MSA is for emergency use. It's not what you fly when you're making a normal entry to an approach. If ATC put you on that radial, the altitude they assigned you would have to be at or above the minimum vectoring altitude (MVA), which is not published.
 
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Yes, that's what I meant. If you arrive at PRADO on V363 northbound, then it's definitely a feeder route for you.

Except I was mistaken, based on what Dtuuri wrote. I would put the odds of his being right about this ten times higher than the odds of my being right about it.
 
Great questions, to which I do not have solid answers. Maybe the instrument proficient pilots/CFIIs/air traffic controllers out there will jump in and set me straight. There is a difference between MSA, and minimum vectoring altitude. My educated guess, (but a guess nonetheless) is that you might be able to get the controller to clear you to a lower altitude so that you don't have so much altitude to lose.

I'm quite certain that ATC will routinely give you an altitude much lower than the MSA on this chart. Look at the radius of the MSA circle: it's 25 NM! The minimum instrument altitude per 9.177 only takes into account obstructions out to 4 NM from your route, which means that in a mountainous area like this, the MVA can often be much lower than the MSA.

If not, then I would guess you want to get vectors to GOLDI so that you have extra time to descend and configure. But then you are going to have to go outbound on the 164 radial, and have to do the procedure turn. In such case, at least they won't give you too steep of a turn to intercept the outbound radial.

Unless you're coming from the north, it would be more efficient to get vectors to the IAF at LAHAB or PDZ, or just fly an airway to one of them.

(In actual practice, they might vector you to intercept the approach course instead.)

(Disclaimer--I'm not instrument rated. Just an instrument student.)

I've been instrument rated for about 22 years, although there are people on this board with far more IFR experience than me.
 
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But PRADO can't be an Intermediate Fix as it doesn't have the letters IF next to it. I'm more confused than I ever was.


I'm betting that it is either a typo or something to do with it being an intersection on an airway.

Your DPE picked a good one. Looks simple, but lots going on...


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I have a link to TERPS on my website. Look for Volume I par 220 (320?). EDIT: par 230!
OK, thanks. So if coming via PRADO there is no IAF. So why isn't PRADO labeled as an IF?
The thing is, when you plan the flight you need to to figure your MIA for any direct legs. Easier to stay on airways to PRADO (if that's where you want to go). After you're on your way, if ATC upsets your plan, then ATC will give you an altitude to maintain until established on a published route segment, "Maintain 3000 until established, procede direct PRADO, cleared for the VOR approach." Assuming you can nav via RNAV, but want the VOR approach, that is.
Again, I conceded a few rounds back that SLI R-043 PRADO wasn't part of a feeder route. But I still don't see why it can't be given as a clearance, along with an altitude assignment, since it can be navigated even /U.
 
It's interesting that the MEA on V16 from PDZ to PRADO is shown as 5000 on the enroute chart, yet on the approach chart, it's 4000 though the two courses are defined by the exact same radial. Any ideas why that might be?

Speculating here, but it might have something to do with the fact that if you were flying V16 eastbound, you would be flying toward higher terrain. If they had set the MEA between PRADO and PDZ at 4000, that would mean that if you were eastbound, you would be allowed to cross PDZ at 4000 and begin your climb to the higher MEA at that point. :dunno:

They could have specified different MEAs for opposite directions of flight, like they did east of SETER, but might not have felt there was an operational need to do so.

When you're flying westbound on the transition route between PDZ and PRADO, none of those issues come into play.
 
OK, thanks. So if coming via PRADO there is no IAF. So why isn't PRADO labeled as an IF?
I think it should be. See Order 8260.19F, page 200, i.(1).

Again, I conceded a few rounds back that SLI R-043 PRADO wasn't part of a feeder route. But I still don't see why it can't be given as a clearance, along with an altitude assignment, since it can be navigated even /U.

Who said it can't? I didn't read all the posts, so I'm not sure why that might be. If you've got en route RNAV equipment I don't see why ATC can't do that along any random route.

dtuuri
 
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