VOR-A Question

[CRLBernstein]

Specifically, the VOR-A at KCON.

http://204.108.4.16/d-tpp/1112/00095VA.PDF

Assuming one is navigating to the CON VOR from the Northwest, on the 330 radial, how are you supposed to get turned around upon crossing the VOR to fly the outbound course for the PT?

 

[tonycondon]

two options i might use.

1 (less likely) right turn to a 45 deg intercept to intercept the outbound and do the procedure turn

2 right turn for direct entry into the holding pattern and do a hold in lieu of procedure turn and shoot the approach out of the hold.

 

[CRLBernstein]

I would also fly a HILPT, since you know the hold is "protected," it just surprised me that it doesn't appear to be charted that way.

 

[tonycondon]

my understanding is that whenever a 'barb' is shown for the procedure turn it is acceptable to do a hold in lieu. if a hold is shown then it is only acceptable to do a hold.

 

[TMetzinger]

As I understand it, the charted hold at CON is for the hold after the missed.

I would expect ATC to give you an altitude limit for crossing CON, (and in the absence of that I'd use 4500 based on the MSA), and no matter where you come from, how you get outbound on the 299 radial is up to you. Just don't go outside the 3500/10NMR floor of the airspace as you manuever to that radial.

 

[seand]

If it were me, I'd do the procedure turn and give a nice leg on the inbound. You've got a fair amount of altitude to lose and getting a good track on the inbound leg before crossing the VOR is critical. The zone of confusion is going to hide your tracking just when you'd want it most here, and don't have long after getting the CDI back to get to minimums.

 

[maddog52]

my understanding is that whenever a 'barb' is shown for the procedure turn it is acceptable to do a hold in lieu. if a hold is shown then it is only acceptable to do a hold.

Exactly!! Just turn into the hold to make the course reversal and complete the procedure.

 

[TMetzinger]

I still think the OP's question was:
"I'm coming in on a course of 150 degrees on the 330 radial. How do I turn around to the 299 radial outbound"?

not

"How do I do the course reversal once outbound on the 299 radial?"


My answer is, any way you wish as long as you stay at a safe altitude.

 

[John Collins]

Specifically, the VOR-A at KCON.

http://204.108.4.16/d-tpp/1112/00095VA.PDF

Assuming one is navigating to the CON VOR from the Northwest, on the 330 radial, how are you supposed to get turned around upon crossing the VOR to fly the outbound course for the PT?

In this case, I would not do a HILPT, although it might be able to be accomplished, it would be very difficult to complete the descents in the time and distances available. Unless the minimum vectoring altitude is lower, the MOCA of 4400 feet along V141 (330 radial) would be applicable. The minimum altitude over the VOR outbound is 3500 feet and the inbound minimum altitude is 2100 feet, which is 1400 to 2300 feet to lose in the hold. Of this, descent below 3500 feet may not commence until established inbound on the 299 degree radial. Then once over the VOR, you have to descend another 940 feet over the 3.1 mile final segment and stabilize at the MDA, followed by a circle to land in the pattern. If you have a DME or an IFR GPS, I presume you could use a distance hold verses the timed hold, as long as you remained within the 10 NM limit, but this would not be my choice.

In my opinion, it would be better to just turn right around 180 degrees after the VOR to intercept the the 299 outbound, descend if needed to 3500 feet, do the procedure turn, and once established inbound descend to the 2100 foot intermediate leg minimum. If you fly the outbound so that the procedure turn will stay inside the 10 NM limit, this will keep you closer to the center of the protected area and allow sufficient time and distance to get established inbound at the proper altitude. You won't be able to commence your descent to the MDA until after you have passed the VOR and the CDI is within 50% of full scale, so I would not want to be high at the FAF inbound. I would want to use a good descent gradient to get down to the MDA with time and distance to spare, so I could locate the runway. Using the lowest practical and safe airspeed will help in regard to keeping the descent rate down.

 

[roncachamp]

Specifically, the VOR-A at KCON.

http://204.108.4.16/d-tpp/1112/00095VA.PDF

Assuming one is navigating to the CON VOR from the Northwest, on the 330 radial, how are you supposed to get turned around upon crossing the VOR to fly the outbound course for the PT?

Turn right.

 

[gismo]

My answer is, any way you wish as long as you stay at a safe altitude.

Agreed. And that safe altitude has nothing to do with the approach or any information on the plate (with the possible exception of the MSA depiction if you're NORDO/emergency). If you are on your own (e.g. cruise clearance or any other approach clearance that didn't include a lower altitude to fly until established) and you're arriving on an airway, the airway MEA is the lowest you can go until established outbound on the published approach. Off airway the MORA applies and in either case your last assigned altitude trumps all. As to which way to turn, I'd go with the direction that gave the shortest turn.

 

[tonycondon]

In this case, I would not do a HILPT, although it might be able to be accomplished, it would be very difficult to complete the descents in the time and distances available. Unless the minimum vectoring altitude is lower, the MOCA of 4400 feet along V141 (330 radial) would be applicable. The minimum altitude over the VOR outbound is 3500 feet and the inbound minimum altitude is 2100 feet, which is 1400 to 2300 feet to lose in the hold. Of this, descent below 3500 feet may not commence until established inbound on the 299 degree radial. Then once over the VOR, you have to descend another 940 feet over the 3.1 mile final segment and stabilize at the MDA, followed by a circle to land in the pattern. If you have a DME or an IFR GPS, I presume you could use a distance hold verses the timed hold, as long as you remained within the 10 NM limit, but this would not be my choice.

In my opinion, it would be better to just turn right around 180 degrees after the VOR to intercept the the 299 outbound, descend if needed to 3500 feet, do the procedure turn, and once established inbound descend to the 2100 foot intermediate leg minimum. If you fly the outbound so that the procedure turn will stay inside the 10 NM limit, this will keep you closer to the center of the protected area and allow sufficient time and distance to get established inbound at the proper altitude. You won't be able to commence your descent to the MDA until after you have passed the VOR and the CDI is within 50% of full scale, so I would not want to be high at the FAF inbound. I would want to use a good descent gradient to get down to the MDA with time and distance to spare, so I could locate the runway. Using the lowest practical and safe airspeed will help in regard to keeping the descent rate down.

most people do a one minute outbound to the PT which would give about a one minute inbound to VOR, same as a standard hold. or you could just fly a 2 minute hold to lose the altitude.

 

[bob_albertson]

my understanding is that whenever a 'barb' is shown for the procedure turn it is acceptable to do a hold in lieu. if a hold is shown then it is only acceptable to do a hold.

Let's go straight to the source

The procedure turn or hold-in-lieu-of-PT is a required maneuver when it is depicted on the approach chart, unless cleared by ATC for a straight-in approach. Additionally, the procedure turn or hold-in-lieu-of-PT is not permitted when the symbol “No PT” is depicted on the initial segment being used, when a RADAR VECTOR to the final approach course is provided, or when conducting a timed approach from a holding fix. The altitude prescribed for the procedure turn is a minimum altitude until the aircraft is established on the inbound course. The maneuver must be completed within the distance specified in the profile view. For a hold-in-lieu-of-PT, the holding pattern direction must be flown as depicted and the specified leg length/timing must not be exceeded.

On U.S. Government charts, a barbed arrow indicates the maneuvering side of the outbound course on which the procedure turn is made. Headings are provided for course reversal using the 45 degree type procedure turn. However, the point at which the turn may be commenced and the type and rate of turn is left to the discretion of the pilot (limited by the charted remain within xx NM distance). Some of the options are the 45 degree procedure turn, the racetrack pattern, the teardrop procedure turn, or the 80 degree $ 260 degree course reversal. Racetrack entries should be conducted on the maneuvering side where the majority of protected airspace resides. If an entry places the pilot on the non-maneuvering side of the PT, correction to intercept the outbound course ensures remaining within protected airspace. Some procedure turns are specified by procedural track. These turns must be flown exactly as depicted

.

These are the teardrop PTs

AIM 5-4-9

 

[John Collins]

most people do a one minute outbound to the PT which would give about a one minute inbound to VOR, same as a standard hold. or you could just fly a 2 minute hold to lose the altitude.

The one minute inbound requires a 1400 foot altitude change. This is a little steep for me. The 2 minute hold would make that more reasonable, but I would prefer just tracking the outbound course and the PT rather than two minutes of DR outbound in the hold.

 

[gismo]

most people do a one minute outbound to the PT which would give about a one minute inbound to VOR, same as a standard hold. or you could just fly a 2 minute hold to lose the altitude.

Actually FWIW, if you fly one minute out, a right 45, another minute, a left 180 to intercept you will be 1.45 minutes out at the point where you roll out on the inbound course (no wind, constant airspeed). If your speed is decreasing during the maneuver you will be further out. If you make the 180 in the same direction as the first 45, you'll only have .55 minutes left to the fix.

 

[poadeleted20]

First, to answer the original question, it's a simple turn-to-intercept problem. You cross the VOR, turn the shortest direction (in this case, right) to roll out on a heading to intercept the outbound (in this case, probably about 330), then intercept and track the 299 radial outbound. When you've flown out far enough to complete the reversal far enough to lose 1400 feet at a safe descent rate, but not so far that you'll exceed the 10nm limit, you reverse course and intercept the 299 inbound before leaving 3500 for 2100.

A classic HPILPT with a 1-minute inbound leg would not be a real good idea, since a 1-minute inbound leg would require an awfully steep descent rate to be down to 2100 before recrossing the VOR. However, since a racetrack pattern is, as the AIM says, perfectly acceptable, you could cross the VOR and then turn right to a heading of 299 (since the race track should be accomplished on the protected side of the radial). When you've flown out far enough to complete the reversal far enough to lose 1400 feet at a safe descent rate, but not so far that you'll exceed the 10nm limit, you turn right again to intercept the 299 inbound before leaving 3500 for 2100.


And there are probably several other ways to do this legally and safely, but personally, I like sticking with one system that works and doing it consistently, since research suggests we do best that which we do most often, and when we do something differently every time, we tend not to do it well. The classic 45-180 PT is my personal choice, because

• That's what I learned to do 40 years ago (law of primacy),
• That's what I've done most often over those 40 years (law of exercise), and
• The numbers for it are printed on the chart (law of simplicity, which though not found in the Aviation Instructor's Handbook, seems patently obvious to me).

BTW, I have no "canned" time to fly out on a PT. The time varies situationally based on altitude to lose outbound and/or inbound. On the VOR 24 at KBDR, with zero altitude loss both outbound and inbound, if I hit the IAF at 1800, I might not go any farther than becoming established outbound before starting the reversal. On the chart above, I'd probably time the outbound to get a 3-minute inbound leg to lose that 1400 feet at a comfortable 500 ft/min.

 

[W. Stewart]

Until just recently, I would have done exactly what Ron and John suggested: turn right essentially 180 degrees to intercept the 299 outbound radial.

Not too long ago, I flew some practice approaches with my original CFI (he is not a CFI-I), and one was very similar to this situation. What he would have done is to cross the VOR and continue essentially on the same course (150 degrees or so) then turn LEFT in a teardrop fashion to intercept the 119 radial INBOUND (299) back to the VOR prior to continuing outbound of the 299 and then the 45/180 turn as depicted on the barb.

Is this teardrop entry wrong for some reason?

Wells

 

[roncachamp]

Until just recently, I would have done exactly what Ron and John suggested: turn right essentially 180 degrees to intercept the 299 outbound radial.

Not too long ago, I flew some practice approaches with my original CFI (he is not a CFI-I), and one was very similar to this situation. What he would have done is to cross the VOR and continue essentially on the same course (150 degrees or so) then turn LEFT in a teardrop fashion to intercept the 119 radial INBOUND (299) back to the VOR prior to continuing outbound of the 299 and then the 45/180 turn as depicted on the barb.

Would you make the turn that same way if the R-299 was part of an airway routing instead of an IAP segment?

 

[W. Stewart]

Would you make the turn that same way if the R-299 was part of an airway routing instead of an IAP segment?

I don't understand your question, Steven. If the VOR is the IAF, one flies to the VOR however one intends to commence the approach henceforth, no?

And besides, I specifically said that I had never done as he suggested--I have always done the RIGHT turn that you answered in your brief response a few posts higher up (and the right turn was also advised by Ron and John).

Wells
(waiting for a response from a knowledgeable CFI-I)

 

[gismo]

Would you make the turn that same way if the R-299 was part of an airway routing instead of an IAP segment?

Have you ever seen an airway routing that involved a 150° course change over a VOR?

 

[gismo]

Until just recently, I would have done exactly what Ron and John suggested: turn right essentially 180 degrees to intercept the 299 outbound radial.

Not too long ago, I flew some practice approaches with my original CFI (he is not a CFI-I), and one was very similar to this situation. What he would have done is to cross the VOR and continue essentially on the same course (150 degrees or so) then turn LEFT in a teardrop fashion to intercept the 119 radial INBOUND (299) back to the VOR prior to continuing outbound of the 299 and then the 45/180 turn as depicted on the barb.

Is this teardrop entry wrong for some reason?

Wells

If I understand correctly you're suggesting continuing past the VOR on your original heading until you're far enough beyond the VOR to complete a standard rate left turn of approximately 210° and fly back across the VOR along the PT outbound course. I do see a couple issues with that concept. One is that unless you give ATC a heads up on your plan you could easily generate a separation loss since the controller wouldn't expect that action. Another is that without some fairly complicated calculation I don't think you could easily determine the proper distance to continue past the VOR before turning back. Finally, depending on terrain you could come closer to obstructions than desirable if you were below the MORA.

 

[W. Stewart]

depending on terrain you could come closer to obstructions than desirable if you were below the MORA.

The MSA in the sector to the SE is actually 600 feet lower than that to the NW. I don't know at what altitude the OP was flying, but, with the procedure turn taking place at 3500, and the MSA to the SE at 3600, and no obstructions shown on the plate, I don't see a problem. The MEA on the V141 is 5000, and MOCA is 4400, so I would think that he would be approaching the VOR on the airway at or above 4400.

If the left turn teardrop is acceptable, I think that would occur at the 4400+, and then descend to 3500 once passing the VOR again on the 299 radial.

Wells

 

[John Collins]

Wells,

I would agree with Lance's post on ATC expectation. One can analyze a specific approach scenario and determine that the teardrop reversal in the opposite direction would be safe from obstacles on a case by case basis, but the TERPS procedure designer has made no considerations for it. It is not described anywhere that I know of as an acceptable method, so in my opinion, your instructor would be hard pressed to explain his actions at the proverbial "hearing".

 

[W. Stewart]

Wells,

I would agree with Lance's post on ATC expectation. One can analyze a specific approach scenario and determine that the teardrop reversal in the opposite direction would be safe from obstacles on a case by case basis, but the TERPS procedure designer has made no considerations for it. It is not described anywhere that I know of as an acceptable method, so in my opinion, your instructor would be hard pressed to explain his actions at the proverbial "hearing".

Thanks, John. Like I said, he is not a CFI-I, but he does have 12,000 hours. He also has never done a parallel entry--he makes a teardrop out of anything not direct.

The actual approach we were flying was at our home base, KZEF.
http://204.108.4.16/d-tpp/1112/05952NG25.PDF

Passing ZEF, having approached from the east, I turned right as I always do to intercept the 062 bearing from the NDB. He told me that he would have continued past ZEF on our 270 heading and turned left to teardrop back to the 062 course back to the beacon prior to proceeding outbound for the depicted course reversal. Given that he has been based out of KZEF for 30 years and has so many hours, I thought that was acceptable.

Wells

 

[poadeleted20]

First, if you fly far enough past the VOR to complete a teardrop on the "far" side of the VOR, you will have departed the airspace the controller planned for you to be in, with the potential for a loss of separation. Second, if you always use a teardrop entry when arriving at a holding fix from the fix end, it is entirely possible that a combination of speed near the holding speed limit and a bad but forseeable wind could put you outside the holding airspace, with both separation and obstruction clearance concerns. Thus, I'd have to question the wisdom of your buddy's techniques.

 

[midlifeflyer]

First, if you fly far enough past the VOR to complete a teardrop on the "far" side of the VOR, you will have departed the airspace the controller planned for you to be in, with the potential for a loss of separation. Second, if you always use a teardrop entry when arriving at a holding fix from the fix end, it is entirely possible that a combination of speed near the holding speed limit and a bad but forseeable wind could put you outside the holding airspace, with both separation and obstruction clearance concerns. Thus, I'd have to question the wisdom of your buddy's techniques.

Anyone with enough knowledge to calculate what amount of wind it would take to be out of protected airspace doing a teardrop entry for anything not parallel?

I'm not quite that extreme but when the boundary between the parallel and teardrop AIM entries are close, I opt for teardrop as the better operational choice for me.

But I'm trying to picture how turning an extra 30° beyond parallel from the non-holding side toward the holding side would take one out of protected airspace. It may be post-Turkey lethargy but I really have trouble visualizing it.

 

[HPNPilot1200]

Not too long ago, I flew some practice approaches with my original CFI (he is not a CFI-I), and one was very similar to this situation. What he would have done is to cross the VOR and continue essentially on the same course (150 degrees or so) then turn LEFT in a teardrop fashion to intercept the 119 radial INBOUND (299) back to the VOR prior to continuing outbound of the 299 and then the 45/180 turn as depicted on the barb.

I'm not saying this is wrong in every situation, but it doesn't seem right to me. I have the same concern that Ron mentions reference to departing the protected airspace while continuing past the VOR.

If I had GPS with turn anticipation capability, I would use that to help begin the turn to join the R-299 outbound. Without GPS, I would cross the VOR and then start a right turn to join R-299 outbound, correcting appropriately for wind.

...to intercept the 119 radial INBOUND (299) back to the VOR prior to continuing outbound of the 299

Also note that tracking the R-119 inbound, east of the VOR is not a published segment of the approach.

 

[CRLBernstein]

I still think the OP's question was:
"I'm coming in on a course of 150 degrees on the 330 radial. How do I turn around to the 299 radial outbound"?

not

"How do I do the course reversal once outbound on the 299 radial?"

That's correct.

Thanks everybody for the discussion - just make the turn in the shortest direction. It's my understanding that TERPS criteria protect the airspace up to a 179 degree turn.

 

[hindsight2020]

My students do this all the time. Even when a 45 180 is perfectly depicted, they go for the "hey sir, Im gonna do a holding procedure!" while I utter under my teeth "..here we go.. [again]". Tight and high after just one minute outbound, we're screaming at the FAF at -2k fpm like the Hindenburg with the 'afterburner' lit, as we blow past our FAF stepdown altitude, I take the aircraft and we do it again. I call it "fancying yourself into corners".

HILO where one is not depicted requires some situational awareness as to the distance you're developing for yourself in order to swing the reversal and stabilize the aircraft in order to effect a configuration change in time to not be behind the flow all the way to threshold crossing. Most people don't have that level of SA, particularly shooting the thing for the first time. So I'd say K-I-S-S.

Good question though. *dusts off the GK book*

 

[poadeleted20]

Anyone with enough knowledge to calculate what amount of wind it would take to be out of protected airspace doing a teardrop entry for anything not parallel?

I'm not quite that extreme but when the boundary between the parallel and teardrop AIM entries are close, I opt for teardrop as the better operational choice for me.

But I'm trying to picture how turning an extra 30° beyond parallel from the non-holding side toward the holding side would take one out of protected airspace. It may be post-Turkey lethargy but I really have trouble visualizing it.

Imagine being on the edge between parallel and direct (i.e., arriving from the holding side on a course nearly perpendicular to the holding course). Add in a big quartering wind from the nonholding side, fix end. Now work out the path flown at 200 KIAS if you try a "textbook" teardrop procedure and compare that to the protected area in TERPS.

 

[midlifeflyer]

Aren't you assuming zero correction to the 30° for the winds? Try zero correction for other entries while outbound and you might run into similar and other troubles. In fact, forget to correct for the wind in a parallel entry and change the big quartering wind to coming from the holding side and see what you get.

Sorry Ron, "if you do it all wrong you'll run into a problem" is not exactly the fault of the procedure.

OTOH, try a by-the-book parallel for the HILPT at BIZEN at KBJC
http://aeronav.faa.gov/d-tpp/1112/05612VD29LR.PDF

Since it's an intersection, you can't head direct back to the intersection using non-RNAV navaids and need to set up an intercept. A standard parallel will put you at the intersection if the winds are 0 and your turns are perfect. No "big winds" needed to mess up this one - just an inbound wind of any number unless you go steeper than standard rate.

 

[poadeleted20]

Aren't you assuming zero correction to the 30° for the winds?

Well, if you figure the wind into it, you're not doing it "by the book," which teaches pure headings. If you know the actual wind and employ the proper corrections, you'll never come close to the edges of the protected space.

Try zero correction for other entries while outbound and you might run into similar and other troubles.

Not unless the wind is really howling. TERPS protected space accounts for something like 90% worst case wind and a pure heading entry.

In fact, forget to correct for the wind in a parallel entry and change the big quartering wind to coming from the holding side and see what you get.

You may end up with a "reverse teardrop," but you won't depart the protected space.

 

[midlifeflyer]

Well, if you figure the wind into it, you're not doing it "by the book," which teaches pure headings.

The I guess we agree. If you put on blinders and eschew situational awareness in favor of blindly following a procedure without accounting for conditions, you will probably have a problem.

Not unless the wind is really howling.

Wasn't really howling the condition you added to show that the teardrop won't work?

I would still like to see the math and a graphic showing how much you would depart protected airspace under your scenario, not "if I add this fact to yours but not to mine I can say that yours won't work - that's how much I like to follow the FAA without question."

 

[RotorAndWing]

I would still like to see the math and a graphic showing how much you would depart protected airspace under your scenario, not "if I add this fact to yours but not to mine I can say that yours won't work - that's how much I like to follow the FAA without question."

 

[John Collins]

The side that the hold or PT is on, provides a greater amount of protection than the non holding side or that opposite the PT. So, I would assume the worst case situation is a hold conducted at the highest possible authorized KIAS and with the howling wind as a crosswind from the holding side to the non holding side. The FAA considers the wind effect based on a maximum of 50 Kts at 4000 MSL and increasing by 3 Kts per additional 2000 MSL. The initial difference between a parallel entry and a teardrop entry in lieu of the parallel entry will result in an additional 30 degrees of turn towards the holding side. The additional 10 seconds of turn is all in the direction of reducing the amount of drift over the parallel outbound course, so I don't see how it could make matters worse.

 

[poadeleted20]

Some folks have the mental math and spatial geometry skills to do all those drift and timing corrections in their head on the fly based on nothing but preflight winds aloft and a CDI needle. My experience as an instrument instructors suggests that most don't. If you can do it, mighty fine -- go ahead. If you can't, the canned solutions will keep you in the protected airspace. Choose wisely.

 

[midlifeflyer]

Thanks John - is that 50 kts a crosswind or a "worst-scenario" wind? For illustration, let's assume an approach with a HILPT at a VOR. The inbound course is 360. The HILPT is on the east side of the inbound course. You're approaching the VOR on a heading of 270 (using Ron's nearly perpendicular scenario).

The "pure" 30° uncorrected) teardrop entry would put you outbound on a heading of 150°. Does the 50 kt assumption assume winds from 330° - a 50 kt tailwind? Is that going to be enough to blow you outside of the protected airspace on the holding side?

And if it is, why wouldn't it also blow you outside of the protected airspace on the holding side if you were approaching the VOR from the northwest on a 150° heading and did a "proper" teardrop entry?

 

[midlifeflyer]

Some folks have the mental math and spatial geometry skills to do all those drift and timing corrections in their head on the fly based on nothing but preflight winds aloft and a CDI needle. My experience as an instrument instructors suggests that most don't. If you can do it, mighty fine -- go ahead. If you can't, the canned solutions will keep you in the protected airspace. Choose wisely.

You're welcome to answer my question about why it would be bad if it were an improper teardrop but ok for a proper teardrop.

I'm sorry Ron. I respect your opinion on most everything but, your repetitious refrain of "choose wisely - follow the recommended procedure and never question it" when you're at a loss for an explanation sounds like an invitation to rote learning and avoiding understanding.

And I definitely =don't= have the mental math and spatial geometry math to do any calculations in flight. Just have found holds where the teardrop is far superior to the recommended parallel and want to learn why it's a bad idea (if it is). Consider the HILPT for the missed at BIZEN in the KBJC VOR/DME 29 without RNAV equipment. A 100% perfect "book" parallel entry with zero will put you at the intersection. If you want to ensure that you intercept the inbound prior to BIZEN, you'll need to change the book (or do a teardrop).

 

[W. Stewart]

In this case, I would not do a HILPT, although it might be able to be accomplished, it would be very difficult to complete the descents in the time and distances available. Unless the minimum vectoring altitude is lower, the MOCA of 4400 feet along V141 (330 radial) would be applicable. The minimum altitude over the VOR outbound is 3500 feet and the inbound minimum altitude is 2100 feet, which is 1400 to 2300 feet to lose in the hold. Of this, descent below 3500 feet may not commence until established inbound on the 299 degree radial. Then once over the VOR, you have to descend another 940 feet over the 3.1 mile final segment and stabilize at the MDA, followed by a circle to land in the pattern. If you have a DME or an IFR GPS, I presume you could use a distance hold verses the timed hold, as long as you remained within the 10 NM limit, but this would not be my choice.

In my opinion, it would be better to just turn right around 180 degrees after the VOR to intercept the the 299 outbound, descend if needed to 3500 feet, do the procedure turn, and once established inbound descend to the 2100 foot intermediate leg minimum. If you fly the outbound so that the procedure turn will stay inside the 10 NM limit, this will keep you closer to the center of the protected area and allow sufficient time and distance to get established inbound at the proper altitude. You won't be able to commence your descent to the MDA until after you have passed the VOR and the CDI is within 50% of full scale, so I would not want to be high at the FAF inbound. I would want to use a good descent gradient to get down to the MDA with time and distance to spare, so I could locate the runway. Using the lowest practical and safe airspeed will help in regard to keeping the descent rate down.

John:

What would you do if you were already IN the holding pattern, say after a missed approach, now holding at 4,000. (In my home base example of KZEF, the same thing exists, with a hold at 4,000 and and inbound floor of 2,100 at the FAF, except that in our case there is the less-accurate guidance of an NDB (and, pre-GPS also no distance/time guidance).

If cleared for a second attempt, would you proceed outbound by DR in the hold for a longer time to decrease the required rate of descent once inbound? Or would you cheat the outbound holding course to the right to intersect the outbound PT course (299 for KCON, or 242 for KZEF) and then proceed to do the 45/180 procedure turn?

I almost started a new thread with the example of the NDB 25 at KZEF, as an ADF approach adds to the complexity and increases the chance for errors. At KZEF, one will typically be at 4,000 approaching the NDB from any direction. Approaching from the north or east, I can see why my instructor might have done his teardrop-at-the-beacon thing prior to beginning the actual approach, to get better alignment and a real position reference when the needle swings. We are talking about 30 or 40 years of survival in a non-radar non-RNAV non-precision environment. I think that one would be far less likely to exceed the 10NM limit if he knows where he IS at some point in time.

Also, does anyone have a reference for turning the shortest way upon beginning the approach? The only reference that I can find, and that requires some inference (from the term "outbound turn", is AIM 5-4-8 (a) (2) "Pilots should begin the outbound turn immediately after passing the procedure turn fix."

Thanks.

Wells

 

[dtuuri]

...when the boundary between the parallel and teardrop AIM entries are close, I opt for teardrop as the better operational choice for me.

The "safe harbor" is per the AIM. Opting out seems to me to require more math than it's worth, not to mention having an official Form 8260.2 in hand detailing which template was actually used for the pattern in question.

But I'm trying to picture how turning an extra 30° beyond parallel from the non-holding side toward the holding side would take one out of protected airspace. It may be post-Turkey lethargy but I really have trouble visualizing it.

Crossing the holding course at a steep angle that specifies a parallel entry, but doing a teardrop instead, causes a delay, while turning, until you can begin timing (when you cross the course again). That puts you further from the fix and elongates the racetrack pattern more than a parallel would.

dtuuri