Procedure Turn Question

azpilot

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azpilot
Reference this approach plate:

https://skyvector.com/files/tpp/2210/pdf/00074IL30C.PDF

Let's say I'm approaching KIWA from PXR. Per the approach plate I fly from PXR to SNOWL at 4600'. When I reach SNOWL, I turn outbound and track the localizer back course. At the same time, I start descending to 3700.

I think I have all of the correct. Here are my questions.

1) At what DME from IWA to I start the procedure turn? There is a note that says I need to remain within 10 DME of IWA. Does that mean I can start the PT at any point after SNOWL, as long as I stay within 10 DME of IWA?

2) When I make the procedure turn, I first turn right to 168 degrees. I fly for one minute, and then I turn to the North at 348 degrees. Is that second turn to the right, or the left? Does it matter? Is the only constraint that I remain within 10 DME of IWA?
 
1) As there is no intersection for the procedure turn, any point after SNOWL would be fine, staying w/in 10mi of SNOWL, not IWA. Note that the PT is shown after a DME of 9.9 in relation to IWA, so IWA is out as the 10mi reference, and note that the diagram references SNOWL intersection so the 10mi is in relation to the SNOWL intersection.

2) The direction of the second turn does not matter, it is your choice. A turn to the left, would give you more time to set up the approach, but a turn to the right would get you on the ground sooner.



edited to clarify that point 2 was in relation to the second turn. The first turn most definitely is to the right.
 
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Procedure Turns A procedure turn barbed arrow indicates the direction or side of the outbound course on which the procedure turn is made. [Figure 1-13] Headings are provided for course reversal using the 45° 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. Some of the options are the 45° procedure turn, the racetrack pattern, the teardrop procedure turn, or the 80°/260° course reversal. The absence of the procedure turn barbed arrow in the plan view indicates that a procedure turn is not authorized for that procedure. A maximum procedure turn speed of not greater than 200 knots indicated airspeed (KIAS) should be observed when turning outbound over the IAF and throughout the procedure turn maneuver to ensure staying within the obstruction clearance area. The normal procedure turn distance is 10 NM. This may be reduced to a minimum of 5 NM where only Category A or helicopter aircraft are operated, or increased to as much as 15 NM to accommodate high performance aircraft.

Instrument flying handbook: Page 1-20

Agree it is remain 10 miles from SNOWL

upload_2022-10-19_12-22-3.png
 
My G530W should tell me my distance from SNOWL. But what if I don't have a GPS? How do I know my distance from SNOWL? I could have DME, but that won't tell me how far away SNOWL is. I mean, 10 miles is a lots of room. But how do I know if don't have GPS?
 
My G530W should tell me my distance from SNOWL. But what if I don't have a GPS? How do I know my distance from SNOWL? I could have DME, but that won't tell me how far away SNOWL is. I mean, 10 miles is a lots of room. But how do I know if don't have GPS?

Timing? If you're doing 120 knots, and the wind isn't significant, you can safely give yourself (say) four minutes in any direction from SNOWL, five if you push it. It's not exact, but it doesn't need to be exactly exact. Alternatively, you could use TFD R-046 as a distance marker (exercise left to the reader :) ).
 
Reference this approach plate:

https://skyvector.com/files/tpp/2210/pdf/00074IL30C.PDF

Let's say I'm approaching KIWA from PXR. Per the approach plate I fly from PXR to SNOWL at 4600'. When I reach SNOWL, I turn outbound and track the localizer back course. At the same time, I start descending to 3700.

I think I have all of the correct. Here are my questions.

1) At what DME from IWA to I start the procedure turn? There is a note that says I need to remain within 10 DME of IWA. Does that mean I can start the PT at any point after SNOWL, as long as I stay within 10 DME of IWA?

2) When I make the procedure turn, I first turn right to 168 degrees. I fly for one minute, and then I turn to the North at 348 degrees. Is that second turn to the right, or the left? Does it matter? Is the only constraint that I remain within 10 DME of IWA?
The Procedure Turn starts at SNOWL. You must remain within 10 NM of SNOWL. You do not have to use DME to do that. DME is not required for the Approach. You do not have to fly the depicted 168/348 'barb.' You are required to do it on the side depicted by the barb.

AIM 5-4-9 a. 1.
1. 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.

EDIT: Well gee, that's already been done
 
1) As there is no intersection for the procedure turn, any point after SNOWL would be fine, staying w/in 10mi of SNOWL, not IWA. Note that the PT is shown after a DME of 9.9 in relation to IWA, so IWA is out as the 10mi reference, and note that the diagram references SNOWL intersection so the 10mi is in relation to the SNOWL intersection.

2) The direction of the second turn does not matter, it is your choice. A turn to the left, would give you more time to set up the approach, but a turn to the right would get you on the ground sooner.



edited to clarify that point 2 was in relation to the second turn. The first turn most definitely is to the right.
That 9.9 DME is HALIB and is there to identify the Missed Approach Fix for TACAN aircraft. It has nothing to do with the PT.
 
My G530W should tell me my distance from SNOWL. But what if I don't have a GPS? How do I know my distance from SNOWL? I could have DME, but that won't tell me how far away SNOWL is. I mean, 10 miles is a lots of room. But how do I know if don't have GPS?
Time, speed and distance. You know your airspeed. You should have a pretty good idea of what the winds are by then so can make a good guess as to your ground speed. And you have a clock.
 
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That 9.9 DME is HALIB and is there to identify the Missed Approach Fix for TACAN aircraft. It has nothing to do with the PT.

I never said it had anything to do with the PT, merely that at 9.9 DME, it would be hard to do the PT after HALIB if the 10nm was in relationship to IWA as the OP initially thought.

The relationship of HALIB to the PT is that on the chart the PT is shown to be further out than HALIB. Therefore, AS ILLUSTRATED ON THE CHART (emphasis added), it would have been 9.9+ miles from IWA, thus disqualifying IWA as the point to stay w/in 10nm when performing the PT.

While, yes, you could do the PT immediately after SNOWL and stay with in the 10nm of IWA, that is kind of pointless as everybody agrees that the 10nm was in relation to SNOWL, not IWA.
 
Timing? If you're doing 120 knots, and the wind isn't significant, you can safely give yourself (say) four minutes in any direction from SNOWL, five if you push it. It's not exact, but it doesn't need to be exactly exact. Alternatively, you could use TFD R-046 as a distance marker (exercise left to the reader :) ).
Hmm. IVVRY, the TFD 046r is 8.5 miles to SNOWL. With a little trigonometry you could calculate a Radial off of TFD to identify 10 miles. I'm a math dummy, but I'm sure someone here can do it.
 
If I'm reading this correct -
  • Fly PXR radial 109 FROM
  • Intercept SNOWL at 3700'
  • Fly IWA radial 123 FROM at 3700'
  • Fly it for 2 min
  • Turn right to 168 degrees for 1 min at 3700'
  • Right tear drop turn back on heading 368 to IWA radial 303 TO at 3700'
  • Left turn on heading 303 following IWA radial 303 TO
  • Switch to Localizer for ILS 30C
  • Descend to 3300' on ILS localizer until SNOWL FAF
Edited to correct barb PT timing
 
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If I'm reading this correct -
  • Fly PXR radial 109 FROM
  • Intercept SNOWL at 3700'
  • Fly IWA radial 123 FROM at 3700'
  • Somewhere on the radial (the turn is somewhere before IVVRY - odd that they don't make it a known fix) turn right to 168 degrees for 2 min at 3700'
  • Right tear drop turn back on heading 368 to IWA radial 303 TO at 3700'
  • Left turn on heading 303 following IWA radial 303 TO
  • Switch to Localizer for ILS 30C
  • Descend to 3300' on ILS localizer until SNOWL FAF
  • Get WAAS GPS and fly RNAV/GPS approach


FTFY
 
Or, this.......

Get vectors to final. A little simpler

upload_2022-10-19_17-20-58.png
 
Hmm. IVVRY, the TFD 046r is 8.5 miles to SNOWL. With a little trigonometry you could calculate a Radial off of TFD to identify 10 miles. I'm a math dummy, but I'm sure someone here can do it.

You could, but I seem to lose 20% of my IQ under the hood or in IMC and would probably botch a calculation like this on the fly (as it were), so I'd probably just use the TFD 046 radial as-is — what's 1.5NM in a context like this?!
 
When I reach SNOWL, I turn outbound and track the localizer back course.
FYI, that isn't the "back course", it's the front course and you want to fly it outbound. The back course is on the other side of the airport and can also be flown both inbound and outbound. See the Aspen (KASE) missed approach procedure for how not knowing the correct meaning of these terms can foul you all up someday.
At what DME from IWA to I start the procedure turn? There is a note that says I need to remain within 10 DME of IWA. Does that mean I can start the PT at any point after SNOWL, as long as I stay within 10 DME of IWA?
Yes, but you'll want to make sure you go far enough outbound to give you enough time to descend to your FAF crossing altitude.

When I make the procedure turn, I first turn right to 168 degrees. I fly for one minute, and then I turn to the North at 348 degrees. Is that second turn to the right, or the left? Does it matter? Is the only constraint that I remain within 10 DME of IWA?
Turning away from the airport helps ensure that you won't short-change yourself on maneuvering room to: intercept final, get established on course and descend to crossing altitude before reaching the fix. Do it that way, away from the airport.

For an in-depth discussion on this subject, see my tutorials Here and slides #53 through #56 here.

Good luck on your test, btw. :)
 
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You could, but I seem to lose 20% of my IQ under the hood or in IMC and would probably botch a calculation like this on the fly (as it were), so I'd probably just use the TFD 046 radial as-is — what's 1.5NM in a context like this?!
Yeah. I wasn't proposing doing it on the fly.
 
FYI, that isn't the "back course", it's the front course and you want to fly it outbound. The back course is on the other side of the airport and can also be flown both inbound and outbound. See the Aspen (KASE) missed approach procedure for how not knowing the correct meaning of these terms can foul you all up someday.

That is certainly an important distinction. Thanks for pointing that out. But I should be reverse sensing the Localizer, right? I think that was why I called it the back course.
 
If I'm reading this correct -
  • Fly PXR radial 109 FROM
  • Intercept SNOWL at 3700'
  • Fly IWA radial 123 FROM at 3700'
  • Somewhere on the radial (the turn is somewhere before IVVRY - odd that they don't make it a known fix) turn right to 168 degrees for 2 min at 3700'
  • Right tear drop turn back on heading 368 to IWA radial 303 TO at 3700'
  • Left turn on heading 303 following IWA radial 303 TO
  • Switch to Localizer for ILS 30C
  • Descend to 3300' on ILS localizer until SNOWL FAF
I'd be off of IWA and on I-IWA long before that. It's the Localizer I'd be intercepting inbound. Not the IWA radial and then change to Localizer after being inbound.
 
That is certainly an important distinction. Thanks for pointing that out. But I should be reverse sensing the Localizer, right? I think that was why I called it the back course.
Only half right, reverse sensing when you go in the opposite direction of the final approach course. The front course is before the airport, the back course is after the airport, always with respect to front course only.
 
I never said it had anything to do with the PT, merely that at 9.9 DME, it would be hard to do the PT after HALIB if the 10nm was in relationship to IWA as the OP initially thought.

The relationship of HALIB to the PT is that on the chart the PT is shown to be further out than HALIB. Therefore, AS ILLUSTRATED ON THE CHART (emphasis added), it would have been 9.9+ miles from IWA, thus disqualifying IWA as the point to stay w/in 10nm when performing the PT.

While, yes, you could do the PT immediately after SNOWL and stay with in the 10nm of IWA, that is kind of pointless as everybody agrees that the 10nm was in relation to SNOWL, not IWA.
You said "...Note that the PT is shown after a DME of 9.9 in relation to IWA..." The PT starts at SNOWL. The depicted 'barb' just happening to be Southeast of the HALLB Missed Approach Fix changes nothing. HALLB has no place even being discussed as pertains to the PT.
 
Most certainly. But I have my instrument checkride one week from today. Trying to make sure I know these things inside and out.
Ah. Smart to review and ask lots of questions. My checkride included one of those barbed PT, VORs, and VOR arc.
 
I'd be off of IWA and on I-IWA long before that. It's the Localizer I'd be intercepting inbound. Not the IWA radial and then change to Localizer after being inbound.

Can’t argue with that. It would work just fine.
 
Can’t argue with that. It would work just fine.
Yeah. The interesting thing is, if you joined the IWA 122r inbound first and then transitioned to the Localizer, you'd have used a PT to get established on the DALKY IAF NoPT Initial Approach Segment.
 
You said "...Note that the PT is shown after a DME of 9.9 in relation to IWA..." The PT starts at SNOWL. The depicted 'barb' just happening to be Southeast of the HALLB Missed Approach Fix changes nothing. HALLB has no place even being discussed as pertains to the PT.

What did I say that was factually incorrect?

The PT is shown after a DME of 9.9 in relation to IWA.

I have said in both of my posts in this thread that the PT was in relation to SNOWL. Here, I'll recap them for you.

First post:
1) As there is no intersection for the procedure turn, any point after SNOWL would be fine, staying w/in 10mi of SNOWL ...

Second post:
... everybody agrees that the 10nm was in relation to SNOWL ...

This is the last post I will make regarding HALLB and SNOWL.

If you still think I do not understand the depicted PT, then so be it.
 
What did I say that was factually incorrect?

The PT is shown after a DME of 9.9 in relation to IWA.

I have said in both of my posts in this thread that the PT was in relation to SNOWL. Here, I'll recap them for you.

First post:


Second post:


This is the last post I will make regarding HALLB and SNOWL.

If you still think I do not understand the depicted PT, then so be it.
You said "...1) As there is no intersection for the procedure turn, any point after SNOWL would be fine, staying w/in 10mi of SNOWL ..."
There IS an Intersection for the Procedure Turn. It is SNOWL. You are calling the Course Reversal part of the PT, the PT. The whole thing is the PT.
 
There is no specific fix to turn 168 degrees on the barbed PT.
 
You said "...1) As there is no intersection for the procedure turn, any point after SNOWL would be fine, staying w/in 10mi of SNOWL ..."
There IS an Intersection for the Procedure Turn. It is SNOWL. You are calling the Course Reversal part of the PT, the PT. The whole thing is the PT.

Let's try this for clarification. There is no intersection for the REQUIRED start of the PT. It is merely where it is permissible to start the PT (SNOWL), with the caveat that the PT must be remain within 10nm of that point (SNOWL). As the quote from the Instrument Flying Handbook below says:
the point at which the turn may be commenced ... is left to the discretion of the pilot

Procedure Turns A procedure turn barbed arrow indicates the direction or side of the outbound course on which the procedure turn is made. [Figure 1-13] Headings are provided for course reversal using the 45° 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. Some of the options are the 45° procedure turn, the racetrack pattern, the teardrop procedure turn, or the 80°/260° course reversal.

Instrument flying handbook: Page 1-20

I hope this suffices to explain my point of view.
 
My G530W should tell me my distance from SNOWL. But what if I don't have a GPS? How do I know my distance from SNOWL? I could have DME, but that won't tell me how far away SNOWL is. I mean, 10 miles is a lots of room. But how do I know if don't have GPS?
Pilots flew procedure turns for many, many years without DME or GPS. It's called "Rate-Time-Distance" navigation.
 
Let's try this for clarification. There is no intersection for the REQUIRED start of the PT. It is merely where it is permissible to start the PT (SNOWL), with the caveat that the PT must be remain within 10nm of that point (SNOWL). As the quote from the Instrument Flying Handbook below says:
the point at which the turn may be commenced ... is left to the discretion of the pilot



I hope this suffices to explain my point of view.
I already knew your point of view. You think that the 'course reversal' part of the PT is the PT. It is just a part of the PT. You said "...There is no intersection for the REQUIRED start of the PT. It is merely where it is permissible to start the PT (SNOWL)..." There is an intersection for the REQUIRED start of the PT. It is SNOWL. Yeah, you may just fly straight out bound for awhile before making any turns. You may decide not to fly outbound on the Localizer at all and do a teardrop method of PT. At SNOWL turn to heading of about say 150, fly that for a minute or so and then a left turn to join the Localizer inbound.
 
There is no specific fix to turn 168 degrees on the barbed PT.
Yup. Nor is there a requirement to use 168 degrees or any particular heading. Nor is there any requirement to fly the Barb at all.
 
Pilots flew procedure turns for many, many years without DME or GPS. It's called "Rate-Time-Distance" navigation.
Yes, but given how slow the Wright Flyer went, ………. :)
 
Yup. Nor is there a requirement to use 168 degrees or any particular heading. Nor is there any requirement to fly the Barb at all.
It’s on the plate. Must follow the plate……..
 
SNOWL is where the procedure turn begins. It is the anchor for the entry zone and maneuvering zone.

The following is a segment of an IAP that has a standard PT:

PT.jpg
 
Good luck on the checkride. You're gonna ace it. The examiner is going to know within 5 minutes it's going to be a pass.
 
I already knew your point of view. You think that the 'course reversal' part of the PT is the PT. It is just a part of the PT. You said "...There is no intersection for the REQUIRED start of the PT. It is merely where it is permissible to start the PT (SNOWL)..." There is an intersection for the REQUIRED start of the PT. It is SNOWL. Yeah, you may just fly straight out bound for awhile before making any turns. You may decide not to fly outbound on the Localizer at all and do a teardrop method of PT. At SNOWL turn to heading of about say 150, fly that for a minute or so and then a left turn to join the Localizer inbound.

Seems to me that we're debating over semantics.

Yes, I am looking at the TURN part of Procedure Turn as where the aircraft is TURNED to execute a course reversal for the purpose of rejoining inbound on the approach.

You, it seems, see the Procedure Turn as the area where the maneuver occurs, regardless of whether the aircraft is turning or not.

However, we're pilots. What does the FAA say?


  • PROCEDURE TURN- The maneuver prescribed when it is necessary to reverse direction to establish an aircraft on the intermediate approach segment or final approach course. The outbound course, direction of turn, distance within which the turn must be completed, and minimum altitude are specified in the procedure. However, unless otherwise restricted, the point at which the turn may be commenced and the type and rate of turn are left to the discretion of the pilot.

    (See ICAO term PROCEDURE TURN.)

  • PROCEDURE TURN [ICAO]- A maneuver in which a turn is made away from a designated track followed by a turn in the opposite direction to permit the aircraft to intercept and proceed along the reciprocal of the designated track.
https://www.faa.gov/air_traffic/publications/atpubs/pcg_html/glossary-p.html#$PROCEDURE TURN


In true FAA fashion it seems there are two recognized definitions but both refer to it being a maneuver to reverse course. The ICAO actually says
A maneuver in which a turn is made...

I understand your point of view, you say you know my point of view, so there is nothing further to add really.
 
Good luck on the checkride. You're gonna ace it. The examiner is going to know within 5 minutes it's going to be a pass.
Thank you for your kind words, and all the encouragement and guidance over the last few years. :)

Your recommendation for the CFII has been spot on. :)
 
When is the checkride? If you haven't already, grill everyone you can who used that DPE on what to expect, etc.
 
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