Changing RNAV TAA Concepts

[aterpster]

Attached is a JPEG of two TAA RNAV IAPs.

The first one is the way it has been done since the inception of TAAs.

The second one is a new concept, which appears to strain the requirements of the TAA order.

I would like to hear views from everyone about the new design concept vs. the long-standing design concept. Think in terms of a non-radar airport.

 

[EdFred]

Hate it. If I'm flying in the clag, and I am down to altitude, I don't want to have to fly a racetrack if I'm coming in from the left or right. If I'm at altitude, I want one turn, none of this fly the wrong way for 4 miles BS. All it does is clog up the system for the guy coming in behind me, or someone waiting to release, and give more time for something to go wrong.

Additionally, they should all be lowercase Ts and not capital Ts. Give us 4 IAFs instead of 3, the only time to fly a racetrack (terrain notwithstanding) is when coming in the "wrong" way to the IAF. If I'm straight in 30 miles away, I should just be able to continue straight in with no PT.

Edit: I hate Jepp charts, and the notes, I might be misreading the new proposal.

 

[Jaybird180]

 

[TMetzinger]

As I read this, if you come from the semicircle on the outside of the IAF (coming from the FAF "side" of the IAF) , you're expected to make a turn inbound (should be no more than 90 degrees). If you come from the other semi circle then you're supposed to do an HILPT to come back in.

I can work with it.

 

[John Collins]

Hate it. If I'm flying in the clag, and I am down to altitude, I don't want to have to fly a racetrack if I'm coming in from the left or right. If I'm at altitude, I want one turn, none of this fly the wrong way for 4 miles BS. All it does is clog up the system for the guy coming in behind me, or someone waiting to release, and give more time for something to go wrong.

Additionally, they should all be lowercase Ts and not capital Ts. Give us 4 IAFs instead of 3, the only time to fly a racetrack (terrain notwithstanding) is when coming in the "wrong" way to the IAF. If I'm straight in 30 miles away, I should just be able to continue straight in with no PT.

Edit: I hate Jepp charts, and the notes, I might be misreading the new proposal.

If you are arriving from the left or the right and the turn to final is 90 degrees or less, you just make one turn and don't fly the hold. If you are arriving from the airport side of the IAF, pass over the IAF, left 80, right 260, or just enter the hold outbound and turn back inbound, what is the big deal, you don't have to fly the full 4 NM. If you are straight in 30 miles away, you just continue straight in with no PT.

 

[dell30rb]

As I read this, if you come from the semicircle on the outside of the IAF (coming from the FAF "side" of the IAF) , you're expected to make a turn inbound (should be no more than 90 degrees). If you come from the other semi circle then you're supposed to do an HILPT to come back in.

That's what I got, and it seems reasonable to me.

 

[EdFred]

As I read this, if you come from the semicircle on the outside of the IAF (coming from the FAF "side" of the IAF) , you're expected to make a turn inbound (should be no more than 90 degrees). If you come from the other semi circle then you're supposed to do an HILPT to come back in.

I can work with it.

If that's the case, I have no issue with the new way of doing things.

 

[azure]

I don't see how this changes which directions require the HILPT. Even the old way, it doesn't look like the NoPT is omni-directional. If you're on the airport side of the perpendicular line through the center IAF or IAF/IF, you do the HILPT, if not you're NoPT. That's how it is on the RNAV into my field. In the old concept the perpendicular line dividing the two regions includes the "T" IAFs. In the new concept there are no "T" IAFs, so you have to go by whether your turn would be > or < 90*.

What am I missing? Like Ed I hate Jepp charts, so there's probably something...

 

[Alexb2000]

I wonder how the new format will be handled if being flown by the autopilot or just following the FD?

Having the NoPT waypoints before made for easy approach loading.

 

[HPNPilot1200]

I wonder how the new format will be handled if being flown by the autopilot or just following the FD?

Having the NoPT waypoints before made for easy approach loading.

On the G1000, it will ask you when loading the approach if you want to complete the course reversal. It does this currently when you load the approach with the center fix (IAF/IF) in the T as the IAF.

 

[n12365]

I like the old format better than the new format, but either one will work. The only time I have been cleared to the center of the T was when I actually had to hold. All of the other times I get cleared to one side of the T and don't have to waste time in the race track. Under the new format, you would have to waste time in the hold approximately half of the time. Maybe I am missing something, is there some advantage to the new format I am not seeing?

Ryan

 

[azure]

I wonder how the new format will be handled if being flown by the autopilot or just following the FD?

Having the NoPT waypoints before made for easy approach loading.

On the 480 I think I'm not going to like it. Currently unless your IAF is one of the NoPT ones, to avoid the HILPT you have to manually suspend at the IF or do a flyleg to the intermediate segment at the last moment, which I personally consider a pain. So if I know I won't need the HILPT, I load one of the NoPT IAFs even if I'm not actually going to cross it, and then bypass it if needed, which is easy and painless. Apparently if they get rid of the NoPT IAFs, the way I hate will be the only one.

 

[flyingcheesehead]

I don't see how this changes which directions require the HILPT. Even the old way, it doesn't look like the NoPT is omni-directional.

The "old" (current) way, if you are coming from the airport side, you simply request the closer of the two IAF's at the ends of the T and fly the appropriate base leg. NoPT is possible from any direction.

 

[gismo]

On the 480 I think I'm not going to like it. Currently unless your IAF is one of the NoPT ones, to avoid the HILPT you have to manually suspend at the IF or do a flyleg to the intermediate segment at the last moment, which I personally consider a pain. So if I know I won't need the HILPT, I load one of the NoPT IAFs even if I'm not actually going to cross it, and then bypass it if needed, which is easy and painless. Apparently if they get rid of the NoPT IAFs, the way I hate will be the only one.

I'm not liking this change for the same reason. If they could add one more IAF slightly further from the runway with a short NoPt segment and a 90° restriction on the turn at that fix I think the 480 problem would be eliminated.

 

[Chip Sylverne]

Hate it. If I'm flying in the clag, and I am down to altitude, I don't want to have to fly a racetrack if I'm coming in from the left or right. If I'm at altitude, I want one turn, none of this fly the wrong way for 4 miles BS. All it does is clog up the system for the guy coming in behind me, or someone waiting to release, and give more time for something to go wrong.

Additionally, they should all be lowercase Ts and not capital Ts. Give us 4 IAFs instead of 3, the only time to fly a racetrack (terrain notwithstanding) is when coming in the "wrong" way to the IAF. If I'm straight in 30 miles away, I should just be able to continue straight in with no PT.

Edit: I hate Jepp charts, and the notes, I might be misreading the new proposal.

I agree with Ed.

 

[RotorAndWing]

Like Ed I hate Jepp charts, so there's probably something...

If you think Jeppesen is bad, you should try Lido charts.

 

[Captain]

Here's another issue to think about,

When doing a holding pattern type course reversal ICAO procedure is to do two turns in the hold if it's a parallel entry. You fly over the fix, fly outbound for a minute and turn in same as the US. But the US we just continue in while ICAO would then do ANOTHER circuit before proceeding inbound.

We all know how ICAO has a way of creaping in to the FAA way of doing things. I'd be for procedures that incorporate as much NoPT as possible for that reason alone.

 

[dtuuri]

When doing a holding pattern type course reversal ICAO procedure is to do two turns in the hold if it's a parallel entry. You fly over the fix, fly outbound for a minute and turn in same as the US. But the US we just continue in while ICAO would then do ANOTHER circuit before proceeding inbound.

ICAO makes you fly the procedural track twice? Got a reference for that?

EDIT: You mean ICAO has you fly the track just ONCE, but the US doesn't? Got a reference for THAT?

dtuuri

 

[dell30rb]

I was taught that ATC does not expect you to make more than one lap around the racetrack. That is, you hit the fix, make your entry, and when you cross back over the fix, you continue on the approach.

I take Captain's statement to mean that ICAO requires you to hit the fix, make an entry, cross back over the fix, and take one more lap around the track before crossing the fix again and continuing on the approach

 

[Captain]

ICAO makes you fly the procedural track twice? Got a reference for that?

EDIT: You mean ICAO has you fly the track just ONCE, but the US doesn't? Got a reference for THAT?

dtuuri

Nope. Every FMS I've flown though when you fly the full approach and the procedure turn is a parallel entry the box flies the turn twice. The reason I've always been given is thats ICAO procedure. We (the US) just do the single reversal.

I'd imagine a reference is out there though. I've just never looked. Maybe someone on PPRUNE would know.

 

[Captain]

I was taught that ATC does not expect you to make more than one lap around the racetrack. That is, you hit the fix, make your entry, and when you cross back over the fix, you continue on the approach.

I take Captain's statement to mean that ICAO requires you to hit the fix, make an entry, cross back over the fix, and take one more lap around the track before crossing the fix again and continuing on the approach

That is correct. 3 total passes over the fix.

 

[EdFred]

I never parallel entry. I just keep my turn coming and teardrop it.

 

[aterpster]

Here's another issue to think about,

When doing a holding pattern type course reversal ICAO procedure is to do two turns in the hold if it's a parallel entry. You fly over the fix, fly outbound for a minute and turn in same as the US. But the US we just continue in while ICAO would then do ANOTHER circuit before proceeding inbound.

We all know how ICAO has a way of creaping in to the FAA way of doing things. I'd be for procedures that incorporate as much NoPT as possible for that reason alone.

I'd like to see your ICAO reference.

In the U.S., it is one lap around the HILPT unless you obtain an amended clearance from ATC to do more than one lap.

 

[Captain]

Okay, I've been doing a little snooping around. From what I've found ICAO annex 2 rules of the air would be the govening body.

This is echoed in Jeppessen's ICAO Airway Manual Gerneral and I'll post a photo below with the relavent section highlighted. Hope it helps...

Again: Holding Patten Procedure turn when Parallel Entry is correct;

US: Fly over once, proceed out, turn toward the hold and proceed over the fix and proceed inbound for the approach. Total times crossing holding fix: 2

ICAO: Fly over once, proceed out, turn toward the hold and proceed over the fix and turn right for one more circuit in the hold. Upon crossing the fix again proceed inbound for the approach. Total times crossing the holding fix: 3

 

[dtuuri]

Okay, I've been doing a little snooping around. From what I've found ICAO annex 2 rules of the air would be the govening body.

This is echoed in Jeppessen's ICAO Airway Manual Gerneral and I'll post a photo below with the relavent section highlighted. Hope it helps...


Again: Holding Patten Procedure turn when Parallel Entry is correct;

US: Fly over once, proceed out, turn toward the hold and proceed over the fix and proceed inbound for the approach. Total times crossing holding fix: 2

ICAO: Fly over once, proceed out, turn toward the hold and proceed over the fix and turn right for one more circuit in the hold. Upon crossing the fix again proceed inbound for the approach. Total times crossing the holding fix: 3

Nothing new there. Same in both places. Your conclusion escapes me.

dtuuri

 

[Everskyward]

Okay, I've been doing a little snooping around. From what I've found ICAO annex 2 rules of the air would be the govening body.

This is echoed in Jeppessen's ICAO Airway Manual Gerneral and I'll post a photo below with the relavent section highlighted. Hope it helps...

Again: Holding Patten Procedure turn when Parallel Entry is correct;

US: Fly over once, proceed out, turn toward the hold and proceed over the fix and proceed inbound for the approach. Total times crossing holding fix: 2

ICAO: Fly over once, proceed out, turn toward the hold and proceed over the fix and turn right for one more circuit in the hold. Upon crossing the fix again proceed inbound for the approach. Total times crossing the holding fix: 3

The page you quoted has instructions for entering and staying in the hold, which is the same as in the US. It doesn't mention using the hold as a course reversal during an approach.

 

[Captain]

Yeah, I see that now. I got so excited when I saw that I posted here without reading it close enough.

Don't worry, I'm back to the drawing board. I've got a few people looking too. That's where I got what I posted. I'm not smart enough to come up with this stuff. Hang on and I'll let ya know what I find...

 

[W. Stewart]

I like the current design better. Having multiple IAF's allows the versatility of providing different altitudes in different sectors. Even if terrain is not a concern, it is nice to be on an established segment of an approach, and having the floor defined for the segment, so one has more peace of mind in descending from one's cruise altitude. Also, losing altitude on a defined straight segment (with one 90 degree turn) is conceptually easier than having to lose altitude in a holding pattern.

Wells
(generally resistant to any changes, but able to adapt)

 

[AdamZ]

Good discussion. What gets me is why the change? Was there a need? Does someone thing this is perhaps safer or less work for ATC in certain areas? Also I note in the second chart ( new ) that depending on the angle that you approach OSBAJ ( IAF) from there is still a no procedure turn option. So looks like all they did was get rid of the two IAFs that were lateral of course, is that correct? Again the question is why?

 

[John Collins]

Good discussion. What gets me is why the change? Was there a need? Does someone thing this is perhaps safer or less work for ATC in certain areas? Also I note in the second chart ( new ) that depending on the angle that you approach OSBAJ ( IAF) from there is still a no procedure turn option. So looks like all they did was get rid of the two IAFs that were lateral of course, is that correct? Again the question is why?

I don't know for sure, but I would guess it has to do with taking up a smaller volume of airspace, particularly as the T style base legs have grown longer. With 6 NM base legs, the TAA would be 72 NM across, whereas without base legs, the TAA is 60 NM across.

 

[aterpster]

I don't know for sure, but I would guess it has to do with taking up a smaller volume of airspace, particularly as the T style base legs have grown longer. With 6 NM base legs, the TAA would be 72 NM across, whereas without base legs, the TAA is 60 NM across.

That is correct because the base legs have grown as a result of Order 8260.54A (lots of other chaos has been created by that order as well as some improvements).

But, I am told that a memo is forthcoming that will relax the requirements and supposedly restore the T configuration in TAA IAPs. I'm not holding my breath.