NoPT Poll

[roncachamp]

I didn't understand that. Hearing "radar services terminated" pretty much means the approach is going below radar coverage and you are on your own. It's not matter of choice to be accepted or rejected.

There's no point in telling the pilot that radar service is terminated because he's being switched to a non-ATC frequency. It's understood that radar services require being on an ATC frequency.

 

[midlifeflyer]

On the parallel entry, you should be intercepting the localizer inbound sometime before TKH. Flying to TKH from BARNE, you intercept the localizer right at the IAF/FAF. With no IF, like the other posters have said, you're required to execute the HILPT.

Do the math. Literally. If you do the standard 1 minute with standard rate turns, a parallel entry puts you exactly on the NDB (it's one of the reasons I prefer a teardrop if it's close).

 

[midlifeflyer]

Well, I don't do ATC anymore, but I'd agree with John in this case. The aircraft is proceeding to a collocated IAF / FAF. I don't think they can clear them for the straight in based on the verbiage in ch4 of the .65. The only example in the .65 that deals with clearing for a straight in with a HILPT, is one where the HILPT is at an IAF well outside the FAF.

Steven would know. He knows everything.:wink2:

OTOH, many would point out that a good number of ATC folks have said for years that, on airspeed, on altitude and on course = straight in. Got into an argument with a CFII who was returned ATP years ago when he was giving me an IPC - he essentially viewed PTS as always optional (wrongly, of course).

 

[roncachamp]

Considering the width of the localizer at that distance, an own-nav intercept should be possible. The clearance was not DIRECT Barnes, but OVER Barnes, so I would maintain 2100 and set up a localizer intercept south of Barnes.

Roll your own vector to final?

 

[Turningfinal]

Do the math. Literally. If you do the standard 1 minute with standard rate turns, a parallel entry puts you exactly on the NDB (it's one of the reasons I prefer a teardrop if it's close).

I've done the math and flown the hold and still don't roll out on top of the holding fix as you opine. After flying outbound for 1 minute and making a standard rate turn, barring any winds, you should still be able to continue that turn to give yourself an intercept before the FAF.

I prefer the teardrop too. I don't even use parallel anymore. Teardrop or direct.

 

[luvflyin]

No. You aren't allowed to skip the hold in lieu of procedure turn unless cleared for the straight in or vectored to final, as this approach is annotated.

You can skip the PT/hold if:

1. NoPT is on the plate for the route being flown,
2. When being vectored to final,
3. When cleared straight-in, or
4. When you're on a timed approach from a holding fix (does anyone do that anymore?).

Otherwise, you must fly it.

I wonder if that hold might be there for #4. Seems kinda weird for a sleepy airport. Does it not have radar?

It's not there for #4. No tower and the missed approach requires course reversal. Timed Approachs are not going to happen

 

[luvflyin]

Why do they indicate the waypoint CFBXL on the approach course? There's no distance or radials to identify where it is.

Now that's a good question. This is a proposed approach and is still under construction. Bet ya see a route to CFBXL by the time it hits the streets

 

[luvflyin]

Do the math. Literally. If you do the standard 1 minute with standard rate turns, a parallel entry puts you exactly on the NDB (it's one of the reasons I prefer a teardrop if it's close).

This brings up a pet peeve of mine. GPS's that decide you should lead the turn and track the radial out bound instead off crossing the fix and flying the parallel heading out bound. I fly a parallel entry the way it was designed to be flown, not the GPS's interpretation of how it should be done. Checkout this approach http://155.178.201.160/d-tpp/1509/05310VA.PDF (VOR-A at KCRQ) I've seen even steeper turns to final before, just can't remember them.

The GPS decides I should lead the turn going into OCN and track the 270r outbound. Now when you make the turn back your going to get to OCN practically off of about a 060 heading and make the turn to final all that much steeper. Fly the entry the way it was designed to be flown and cross OCN and then turn to the oubound parallel heading (correct for the wind dammit) you'll be getting back to OCN after having a little time to join the 270r inbound before crossing OCN and making that turn to final.

TERPS guys??? Please tell me they haven't recalculated and made the Templates smaller because GPS's think were going to be right smack dab over the pretty black lines.

 

[luvflyin]

My guess is if this same approach was at a much busier place, or this place was much busier, then they would probably go through the trouble to establish an intermediate fix, move the barnes transition a couple of degrees to the left to join it and NoPT it. TERPS experts?? any terrain or NAVAID issues to prevent this?

I took the trouble to look at the enroute chart around there. HEZ is the only thing available. May be some traffic reason not to add an HEZ transition. Maybe Houston and Memphis Centers don't want to get involved with a little extra coordination. It wouldn't save airplanes arriving from the generally east side anything anyway over just doing the damn procedure turn.

 

[Turningfinal]

Now that's a good question. This is a proposed approach and is still under construction. Bet ya see a route to CFBXL by the time it hits the streets

It's a Computer Navigational Fix (CNF) and can be identified by the parenthesis around a 5 letter fix. Many of them also begin with CFxxx. It's really only used for internal coding of FMS and GPS systems and started getting published on approach plates after the AA965 accident in Colombia in order to allow pilots to cross check the database.

You won't see a feeder route to CFBXL, since you can neither file to that point nor can ATC clear you to it per the AIM.

 

[luvflyin]

It's a Computer Navigational Fix (CNF) and can be identified by the parenthesis around a 5 letter fix. Many of them also begin with CFxxx. It's really only used for internal coding of FMS and GPS systems and started getting published on approach plates after the AA965 accident in Colombia in order to allow pilots to cross check the database.

You won't see a feeder route to CFBXL, since you can neither file to that point nor can ATC clear you to it per the AIM.

I get it that a CFxxx is there for the GPS to get it's head wrapped around some kind of fix on the localizer a ways before the FAF. I think I recall that I've seen Approaches where a Terminal Route makes a bend at those. Can anyone find one?? This Approach is begging to have a route from HEZ to join the localizer and then straight in. The CFxxx could be renamed or just left as is if I'm correct that routes can go over CFxxx's. My guess is that ATC would be the stumbling block because they don't like approaches that cross center boundaries, in this case it's an approach that starts in Houston's sky and ends in Memphis's.

 

[roncachamp]

It's a Computer Navigational Fix (CNF) and can be identified by the parenthesis around a 5 letter fix. Many of them also begin with CFxxx. It's really only used for internal coding of FMS and GPS systems and started getting published on approach plates after the AA965 accident in Colombia in order to allow pilots to cross check the database.

When you do see CNFs they're generally found on a procedure track or an airway, not freestanding like this one.

You won't see a feeder route to CFBXL, since you can neither file to that point nor can ATC clear you to it per the AIM.

So says the AIM, but ATC procedures are found in Order JO 7110.65 and that weighty tome says nothing at all about CNFs.

It looks to me like the approach designer was trying to make procedure entry at CFBXL, probably via a radial from HEZ. The problem is you can't dead end a feeder route on a localizer without some positive fix at that point and there's just nothing there to work with.

 

[roncachamp]

I get it that a CFxxx is there for the GPS to get it's head wrapped around some kind of fix on the localizer a ways before the FAF. I think I recall that I've seen Approaches where a Terminal Route makes a bend at those. Can anyone find one?? This Approach is begging to have a route from HEZ to join the localizer and then straight in. The CFxxx could be renamed or just left as is if I'm correct that routes can go over CFxxx's. My guess is that ATC would be the stumbling block because they don't like approaches that cross center boundaries, in this case it's an approach that starts in Houston's sky and ends in Memphis's.

A route from HEZ to CFXBL would require a fix at that point that could be determined by something other than GPS. It's too far for HEZ DME and there's no other NAVAID with the proper geometry to form an intersection.

 

[azure]

A route from HEZ to CFXBL would require a fix at that point that could be determined by something other than GPS. It's too far for HEZ DME and there's no other NAVAID with the proper geometry to form an intersection.

A route could be defined from HEZ to any point along the localizer using a radial, and a fix defined at the intersection, could it not? Is not CFXBL on the localizer course? It's hard to say for sure but based on the prototype plate, it sure looks like it to me...

 

[roncachamp]

A route could be defined from HEZ to any point along the localizer using a radial, and a fix defined at the intersection, could it not? Is not CFXBL on the localizer course? It's hard to say for sure but based on the prototype plate, it sure looks like it to me...

No, it could not. That's not permitted due to the possibility of false localizer courses. The problem became known due to an incident in Canada about fifteen years ago. The bizjet was being flown by the AP when it made the turn to join the localizer too early. The flight crew recognized the error and took action so no harm was done and the incident did not appear in the general news.

 

[aterpster]

It looks to me like the approach designer was trying to make procedure entry at CFBXL.

When I load the approach starting at BARNE the CNF does not appear. But, when I activate VTF CFBXL appears as the first fix. It seems it is there to provide a 6-mile pseudo intermediate segment for vectors to final.

 

[Kritchlow]

Voted would not do it. That said, I may tell them. They may never know. I don't truly think it's required. It's certainly not required to do it as trained. You can whip a quick 330. Straight in, what's the difference??

 

[azure]

No, it could not. That's not permitted due to the possibility of false localizer courses. The problem became known due to an incident in Canada about fifteen years ago. The bizjet was being flown by the AP when it made the turn to join the localizer too early. The flight crew recognized the error and took action so no harm was done and the incident did not appear in the general news.

Interesting, thanks for the info. So then you would need another cross radial to define the fix, from MHZ, perhaps.

 

[taters]

No, it could not. That's not permitted due to the possibility of false localizer courses. The problem became known due to an incident in Canada about fifteen years ago. The bizjet was being flown by the AP when it made the turn to join the localizer too early. The flight crew recognized the error and took action so no harm was done and the incident did not appear in the general news.

Happens everyday in ORD to any plane that doesn't have an automatic transition to the ILS landing west (RJ's) . Boeing and Airbus have a high-fidelity signal generated by the FMS itself as long as the signal is "valid" which is why they dont have to push a "VLOC" type button ...the rub is the high-fidelity code is uber expensive to test/certify/purchase...most autopilots will try and intercept a false loc and Bombardier even put out a directive not to select appch mode until "movement of the localizer is witnessed". (most just use GPS to intercept ) and I dont see the danger in doing that here if your equipped.

All you need is a IF of HEX within 18 miles of the loc...(a DME on the loc a nice expenditure of tax funds IMO).

 

[NoHeat]

Now that's a good question. This is a proposed approach and is still under construction. Bet ya see a route to CFBXL by the time it hits the streets

The old LOC-only approach plate has the same CFBXL fix. So it's not something new for the proposed ILS approach.

I think it would make a decent IAF, if a radial from a VOR were specified. But that didn't seem to be the plan, since they didn't do it for the old LOC-only plate.

 

[dmspilot]

It's a Computer Navigational Fix (CNF) and can be identified by the parenthesis around a 5 letter fix.

Also can be identified by using an X instead of a triangle.

 

[roncachamp]

Interesting, thanks for the info. So then you would need another cross radial to define the fix, from MHZ, perhaps.

We tend to think of VOR radial intersections as forming nice sharp points in space, but they don't. They form a quadrilateral, the area they cover is determined by the distance from the VORs and the angle of intersection. CFBXL is 35 miles from HEZ and fifty miles from MHZ, so we're already beyond the Standard Service Volume. I didn't do the arithmetic for this one but I suspect an intersection here would exceed the maximum fix error even if an Expanded Service Volume was possible at useful altitudes.

 

[azure]

We tend to think of VOR radial intersections as forming nice sharp points in space, but they don't. They form a quadrilateral, the area they cover is determined by the distance from the VORs and the angle of intersection. CFBXL is 35 miles from HEZ and fifty miles from MHZ, so we're already beyond the Standard Service Volume. I didn't do the arithmetic for this one but I suspect an intersection here would exceed the maximum fix error even if an Expanded Service Volume was possible at useful altitudes.

Yes, I noticed that MHZ was a bit far away, didn't bother to measure the distance though. So probably not much point to establishing an IF that only RNAV-equipped aircraft can use, especially since there is already an RNAV(GPS) 36 with LPV minimums, and a nice one at that, an old style T approach with TAA defined with sensible NoPT sectors. If I was going in there, I'd choose that one over the proposed ILS in almost every conceivable situation (assuming the new lighting system allows a reduction in the vis requirements for the LPV as well).

 

[John Collins]

Approach designers use the navigation aids that are available at hand to design the approach procedure. When they run out of options to create fixes, they use the PT or Hold in Lieu of a PT (HILPT) and a facility such as the NDB in this case to navigate to the the approach. The purpose of the HILPT in this case is allow joining the intermediate leg which is also aligned with the final approach course along the localizer path. A PT or HILPT according to CFR 14 Part 97.3 is:

Procedure turn means the maneuver prescribed when it is necessary to reverse direction to establish the aircraft on an intermediate or final approach course.

In this case, it is necessary for both purposes as the intermediate leg and the final approach course are the same.

Even if radar was available on this approach, a controller is not permitted by FAA guidance to intercept the aircraft at the FAF unless the conditions are effectively VMC or the pilot requests it. Otherwise, they are required to intercept the aircraft at a point roughly 3 NM from the FAF (2 NM outside the gate) and at an altitude that is below the GS. This permits an aircraft to get established on the intermediate leg and to capture the GS if automation is used. I certainly would not request a radar vector intercept to the FAF on an ILS unless I was in visual conditions.

 

[luvflyin]

We tend to think of VOR radial intersections as forming nice sharp points in space, but they don't. They form a quadrilateral, the area they cover is determined by the distance from the VORs and the angle of intersection. CFBXL is 35 miles from HEZ and fifty miles from MHZ, so we're already beyond the Standard Service Volume. I didn't do the arithmetic for this one but I suspect an intersection here would exceed the maximum fix error even if an Expanded Service Volume was possible at useful altitudes.

Yeah. Probably no way it could work. +/- 4.5 degrees is what is used for Radial error when plotting out most of this stuff. A liitle to the left and you'd never see the localizer, little to the right and you'd get it beyond it's limits. I suppose a transition could be made off of HEZ direct to the NDB and save the guys flying in from that direction a little time over going to BARNES first but it probably wouldn't be worth the hassle it created in coordination between Houston and Memphis.

 

[aterpster]

In this case, it is necessary for both purposes as the intermediate leg and the final approach course are the same.

This type of ILS design does not have an intermediate segment. The inbound course of the HILPT serves the same function. Check the TERPs maps under the coordination tab for this proposed ILS.

Also 8260.3B, Para 234 e (1).

 

[aterpster]

especially since there is already an RNAV(GPS) 36 with LPV minimums, and a nice one at that, an old style T approach with TAA defined with sensible NoPT sectors.
T-Leg TAAs are going away, with a few exceptions. The revised RNAV criteria make them impractical. This approach is being amended along with the ILS. The new TAA will not have T legs.

https://www.faa.gov/air_traffic/fli...2011112224931201002-TVR&type=acifp&nasrId=TVR

Open up the "S" folder to see the new RNAV 36 IAP.

 

[roncachamp]

Yeah. Probably no way it could work. +/- 4.5 degrees is what is used for Radial error when plotting out most of this stuff. A liitle to the left and you'd never see the localizer, little to the right and you'd get it beyond it's limits.

4.5 degrees for the tracked radial, 3.6 degrees for the intersecting radial. The difference is the error contributed by the pilot.

I suppose a transition could be made off of HEZ direct to the NDB and save the guys flying in from that direction a little time over going to BARNES first but it probably wouldn't be worth the hassle it created in coordination between Houston and Memphis.

HEZ direct TKH is an acceptable nonradar route. The difference in coordination would be to enter HEZ..TKH in the Flight Data Processing computer instead of HEZ.V245.BARNE..TKH.

 

[midlifeflyer]

Even if radar was available on this approach, a controller is not permitted by FAA guidance to intercept the aircraft at the FAF unless the conditions are effectively VMC or the pilot requests it. Otherwise, they are required to intercept the aircraft at a point roughly 3 NM from the FAF (2 NM outside the gate) and at an altitude that is below the GS. This permits an aircraft to get established on the intermediate leg and to capture the GS if automation is used. I certainly would not request a radar vector intercept to the FAF on an ILS unless I was in visual conditions.

The key is in bold, given the way the question was asked.

I might request direct to a point 3 south of the NDB to intercept the localizer. Or 6 south, where the CNF is located (without, of course, mentioning the CNF itself).

But I wonder how the approach gate fits in with the PT (I was going to your my hypothetical approach from the northwest as the example, but no need to). Let's see, 1 minute outbound at 90 kts in a 172 or Warrior is... uh-oh! Only 1.5 miles outbound before the inbound turn.

 

[azure]

T-Leg TAAs are going away, with a few exceptions. The revised RNAV criteria make them impractical. This approach is being amended along with the ILS. The new TAA will not have T legs.

https://www.faa.gov/air_traffic/fli...2011112224931201002-TVR&type=acifp&nasrId=TVR

Open up the "S" folder to see the new RNAV 36 IAP.

Yeah, I was surprised to see this one still adhering to the old design. A pity. I preferred those because they're easier to skip over the HILPT with the 480 when coming from the "outside" half plane. What exactly were the reasons for phasing out the T legs?

 

[aterpster]

Yeah, I was surprised to see this one still adhering to the old design. A pity. I preferred those because they're easier to skip over the HILPT with the 480 when coming from the "outside" half plane. What exactly were the reasons for phasing out the T legs?

The "new" RNAV criteria has complex formulas for calculating TF leg distance that varies with the magnitude of the course change and altitude. They can still do the T-leg design but the legs need to be longer, so much so at higher altitudes that it causes the TAA areas to be loo large for airspace management.

 

[dmspilot]

This type of ILS design does not have an intermediate segment. The inbound course of the HILPT serves the same function.

Maybe it is not explicitly "constructed" for TERPs criteria, but the inbound course of the HILPT *is* the intermediate segment.

The intermediate segment, normally aligned within 30° of the final approach course, begins at the IF, or intermediate point, and ends at the beginning of the final approach segment. In some cases, an IF is not shown on an approach chart. In this situation, the intermediate segment begins at a point where you are proceeding inbound to the FAF, are properly aligned with the final approach course, and are located within the prescribed distance prior to the FAF.

 

[dmspilot]

But I wonder how the approach gate fits in with the PT (I was going to your my hypothetical approach from the northwest as the example, but no need to). Let's see, 1 minute outbound at 90 kts in a 172 or Warrior is... uh-oh! Only 1.5 miles outbound before the inbound turn.

You're comparing a HILPT based on time versus the criteria for radar vectoring which is always the same distance regardless of the speed of the aircraft. I don't think it's a fair comparison.

 

[midlifeflyer]

You're comparing a HILPT based on time versus the criteria for radar vectoring which is always the same distance regardless of the speed of the aircraft. I don't think it's a fair comparison.

You are missing the point of the comparison. I'm not comparing HILPT procedures with radar vectors.

I'm making a comparison between being at 2100' at the FAF and being at 2100' at the FAF.

The reference to vectoring is only to answer an objection - that the vectors will get you established in time while BARNE → NDB will not. Point is, neither will the PT if done from the northwest.

 

[dmspilot]

Point is, neither will the PT if done from the northwest.

Why not?

 

[Velocity173]

Approach designers use the navigation aids that are available at hand to design the approach procedure. When they run out of options to create fixes, they use the PT or Hold in Lieu of a PT (HILPT) and a facility such as the NDB in this case to navigate to the the approach. The purpose of the HILPT in this case is allow joining the intermediate leg which is also aligned with the final approach course along the localizer path. A PT or HILPT according to CFR 14 Part 97.3 is:



In this case, it is necessary for both purposes as the intermediate leg and the final approach course are the same.

Even if radar was available on this approach, a controller is not permitted by FAA guidance to intercept the aircraft at the FAF unless the conditions are effectively VMC or the pilot requests it. Otherwise, they are required to intercept the aircraft at a point roughly 3 NM from the FAF (2 NM outside the gate) and at an altitude that is below the GS. This permits an aircraft to get established on the intermediate leg and to capture the GS if automation is used. I certainly would not request a radar vector intercept to the FAF on an ILS unless I was in visual conditions.

John, what is the reference for doing the straight in from a FAF based in "VMC or the pilot requests it."? That criteria could be loosely based on 5-9-1 (1&2) but I'm not sure that could be applied in this case. It would seem that 4-8-1 c is the overriding rule here and I don't see any way of getting out of the HILPT when the aircraft is direct a IAF that also serves as a FAF.

 

[aterpster]

Maybe it is not explicitly "constructed" for TERPs criteria, but the inbound course of the HILPT *is* the intermediate segment.

If it is not constructed as a segment it is not an approach segment. The handbook statement is correct most of the time. But, it does not cover that type of LOC/ILS that does not have an intermediate segment.

 

[midlifeflyer]

Why not?

Fully described in an earlier post.

But to briefly summarize, a standard FAA parallel entry from the northwest done as described in the AIM guidance with standard rate turns will put you over the NDB at about a 30° intercept to the localizer at 2100'. 3X the intercept angle from BARNE, at the same altitude.

A sharper turn on the inbound of the parallel entry might let you intercept the localizer earlier but not by much. Even getting to the approach gate itself would be iffy since you have only gone about 1.5 NM outbound (at a 90 KT holding speed), let alone 2-3 miles beyond it.

In the drawing, the one thing that is incorrect is that I traced the holding pattern, which is not to scale. At a 90 KT holding speed, the airplane would be just beyond the approximate location of the appraach gate when it began the reversal.

 

[dmspilot]

If it is not constructed as a segment it is not an approach segment. The handbook statement is correct most of the time. But, it does not cover that type of LOC/ILS that does not have an intermediate segment.

Every approach has an intermediate segment.

 

[dmspilot]

Point is, neither will the PT if done from the northwest.

I don't agree.

Fully described in an earlier post.

But to briefly summarize, a standard FAA parallel entry from the northwest done as described in the AIM guidance with standard rate turns will put you over the NDB at about a 30° intercept to the localizer at 2100'. 3X the intercept angle from BARNE, at the same altitude.

It is not as difficult to intercept the localizer before the FAF with a parallel entry HILPT as you make it seem. You aren't supposed to backtrack on the inbound course during a parallel entry, and your intercept angle is quite shallow, I recommend a minimum of 45º. While it would normally be difficult to intercept a localizer at such a large angle, you have an NDB to help you.

On the other hand, flying from BARNE direct to the NDB makes it impossible to intercept the localizer before the FAF.