GPS Approach Peculiarities

[Peter Grey]

Well this has generated a lot of discussion.

The cleared route of flight was KWANG direct CMA. I don't know where V27 got into this discussion but V27 was not part of the flight plan. Note that KWANG direct CMA is not V27.

Now what ended up happening is that Todd requested the RNAV 8 approach, and I cleared him direct DEANO for that approach. He was near KWANG when that happened but wasn't cleared direct DEANO after KWANG. By happenstance he ended up near a direct path from KWANG to DEANO.

My measurement had the turn at 90 degrees and therefore legal by ATC rules. Based on PE aware he arrived on a track of around 85 which would be a 82 degree intercept (if he had arrived from KWANG we would see a track of 70 which would be a 97 degree intercept). It's worth noting that with KWANG only 5 NM from DEANO small cross track differences make large angular differences. I will mention that the pilot does not need to worry about these rules, they are quite complex and relate to very specific circumstances. However in this case per ATC rules the max intercept is 90 degrees.

To answer the specific questions brought up:

I planned my route to go direct to DEANO (that's amore?). Since I was given DIRECT Deano I wasn't technically on the V27 Airway so I got to disregard the "Procedure NA for V27 Eastbound" note. First peculiarity (deviation?).

No deviation here, and even if it was an illegal clearance (it wasn't), it's not a rule a pilot can be busted on (show me the reg that you would be violating).

Anyway, 90 degree right turn south out of DEANO to HATLI ensues. When I briefed the approach I Read "No PT" from this FEEDER Fix and interpreted that to mean no PT/ HOLD to turn to Final approach course 073. Another 90 degree turn left to 073 and FAC.

Having hand flown those somewhat ugly turns, I'm thinking that maybe that's not what the FAA really wants you to be doing...

Nope you flew the track correctly, NoPT means NoPT, you don't fly the course reversal. This is standard fare on RNAV approaches.

Oh, as an aside I filed KWANG DEANO and that was modified into KWANG CMA...I'm pretty sure I don't have to file to a VOR, any ideas why my intersection got axed on the routing?

KWANG CMA is the TEC route.

I assume "Procedure NA for arrivals at DEANO via V27 eastbound" is because that would require a 96 degree turn. I'm still not clear if Todd was on V27. I understand that he was given "direct DEANO", but PEaware seems to indicate that he was given that instruction after reaching KWANG. Isn't he still arriving at DEANO on V27?

This is where that small lateral distance = large angular distance matters. He was very close to the KWANG to DEANO path, but that difference = 15 degrees making it a legal clearance.

I was monitoring PE last night and heard some of the radio exchanges between a pilot who was unable to navigate direct to KWANG. Apparently there was another plane in the area also needing to go through KWANG and this was creating a "traffic jam". Same pilot? Not sure but it seems likely. Perhaps the navigation error was so "gross" that it was only happen stance the flight path was near KWANG.

Todd was not this pilot. Todd was affected by this pilot but the end result was that Todd did get cleared direct KWANG and properly navigated there.

"N123AB, you are 8 miles from HALTI, turn right heading 130, cleared RNAV GPS runway 8 approach"

This isn't legal as the max intercept on a vector to final is 30 degrees.

Ryan has the correct details on other ways to do this approach, however the way that was done was legal.

[Ryan B]

Ryan,

Small point, but the distance from HATLI is not required in the clearance since he's not being vectored to the final app course, correct? Only the altitude would be required since he'd be on a random route to HATLI.

There's a debate at my facility on this. I can't find a solid part in the book that allows me to skip the distance in the approach clearance. If you can find one let me know where. We've scoured the 65 in search of how to omit that.

I think a lot of controller just omit it because it seems redundant right? Now I'm going to look at it again hehe.
EDIT: I looked at it again. I think the confusion area is 7110.65 5-9-4a: ARRIVAL INSTRUCTIONS.

If you believe this paragraph is only about VTF then you're right, you wouldn't need the distance from the fix or airport if you cleared someone direct the IAF. People in my facility are hard headed and hate change hehe. The way I was taught is that you still need the distance because of 5-9-4a (meaning that section isn't just referring to VTF). But it certainly seems that the .65 is only meaning when vectoring to final.
Example 1 really makes the thing gray hehe. The aircraft was being vectored to FAC, but then the clearance was omitted. He was ALREADY established on the FAC and the example STILL gives the distance from the FAF.
Then see 5-9-5 example a page further... (GOLLF FORRE FAF) - this example is more realistic to what is being done here (assuming the pilot went direct HATLI instead of DEANO anyway)... the example issues distance from the IF.

After reading through all that again. I have a solid answer for you: I'm not sure what the rule is!

Peter, do you mean to say the pilot was on a track that would create a turn from PPOS to DEANO at less than 90 degrees? I presume this is what was done...

[Peter Grey]

Peter, do you mean to say the pilot was on a track that would create a turn from PPOS to DEANO at less than 90 degrees? I presume this is what was done...

Yes, the pilot turned around 80 degrees at DEANO.

By chance that track was close to the KWANG to DEANO track which generated the discussion here.

[Ryan B]

Thanks for that.

[Peter Grey]

With regards to the "distance from the FAF" side discussion.

Here's what the book says:

Issue all of the following to an aircraft before it
reaches the approach gate:

a. Position relative to a fix on the final approach
course. If none is portrayed on the radar display or if
none is prescribed in the procedure, issue position
information relative to the navigation aid which
provides final approach guidance or relative to the
airport.

The example is weird because it splits the distance into a later transmission, but that's ok as long as it's issued before the approach gate.

While it's common to give everything in that list in 1 transmission (Distance, vector, clearance, and altitude) you can actually split them up legally.

Technically this sequence is legal (if not a waste of radio time).

"Cessna 12345 maintain 5000' till established on the localizer"

"Cessna 12345 fly heading 300"

"Cessna 12345 cleared ILS 28R approach"

"Cessna 12345 5 miles from FINLE"

In terms of this only being applicable to a VTF approach. This is in the "radar arrivals" section of the .65. A radar arrival is defined as (From the P/CG):

An aircraft arriving at an
airport served by a radar facility and in radar contact
with the facility.

So that read does seem to imply you always need to give a distance for an approach clearance when radar is involved (aka you aren't using procedures that would also work if the radar went out).

So I'm going to agree with Ryan on this one.

[Ryan B]

Difficult to nail it down for certain though.

I'm trying to ask the guys at the FSDO this question... we'll see what they say.

[Peter Grey]

So my math in the description I gave was wrong (thanks Ken!) so ignore that part of it (I'll edit it out).

The theory is still correct, just that 750' deviation note is off by a factor. The actual amount isn't relevant to the discussion so I'm not going to go into details on that calculation.

[Talan2000]

Wow, another great discussion, I really feel like we are bringing the band back together! And of course my chest swells with pride at being vindicated, on multiple fronts, by none other than Peter himself -- definitely a worthwhile training flight!

Keith, as always thanks for helping improve precision in terminology. DEANO is definitely an Initial approach fix (IAF) and not a "feeder fix". The funny thing is, even though it is an IAF, it sure kinda looks & acts like a "feeder fix" would since it is pointing at another IAF (transformed into an IF once you use DEANO as an IAF), has a defined segment, procedure guidance (No PT), and altitude. Probably just getting too into the weeds.

Also glad to hear that my initial briefing of the approach and execution of it was correct before I started post flight second guessing. No PT means no HOLDING entry in this case. It's just seems funny that the FAA isn't exactly being super precise here in terminology since a procedure turn (PT) isn't exactly the same thing as a Hold. I assumed, correctly, that No PT would include holds in this instance. Probably just getting too into the weeds. My ancient training predated GPS so their conventions are still somewhat foreign.

Funny thing about turns isn't it - sometimes 90 is ok, 91 is not. Guess a man has to know his limitations. 10 NM is plenty of time to get your "stuff" together on the FAC at 90-100kts. I look forward to watching your video of doing it in a more challenging environment. My airmanship wasn't really all that bad - exempting the 200 ft altitude loss heading S out of DEANO for foolishly looking at my iPad for too long and I find the default 172 to be a pain to hand fly but as my RW training resumes in similar though easier to trim 172 I'll stick with it.

As to Ken and Mr Burns V27 questions - Peter pretty much handled that. As for my understanding, as soon as I am cleared DIRECT, I am NOT on an airway even if my track exactly overlays that airway. For example, in the past, I've considered asking for DIRECT APLES on an I-rating test when heading to VCV and its arcing approach for this reason -- the airway MEA is WAY high once you are north of the mountains and the controller can't get you lower because of it. But I believe if one got a Direct clearance to APLES he could give you lower...

Anyway, also glad that everyone knows I wasn't the cause of any aerial traffic jam. There was an "adventurous" kid flying about that evening, and I was cheering him on until he started arguing that he was already descending when Peter twice requested him to do so and shortly thereafter broadcast that he was "losing control of the airplane"...in any case all this amusement took place before I ever even turned east departing KSBA. I broadcast, "we have control of our aircraft and will head to KWANG" when Peter directed that. I thought it was funny anyway

Steve - great question about the circling - what was I thinking? Well, I was thinking there was a howling wind out of the west and no way I was landing on RWY 8 and also thinking there was no way I was going to fly ALL THE WAY around to set up for an approach into Rwy 26. The solution - the wonderful circling to land option - fly the approach to one runway then visually orbit the field to land on another runway. It can get you into trouble or it can save you. I knew the wx was pretty good so I was comfortable circling even at night/dusk even at min altitude (below Traffic Pattern Altitude). All legal.

As to the TEC routes, mea culpa, you are right the "monster got me." I never even considered looking for a TEC route for a 39 NM flight. It's a foreign practice to those of us in the Great State of Texas. That said, filing IFR without using a TEC route is 100% legal. On PE, your routing will probably just get changed 100% of the time, too! I was caught off guard and stumbled on the readback for this reason...and also because i was trying to scribble with my iPad running WingX and it's "notepad" function and I couldn't squeeze in "camarillo" wiht my fingernail. I'm not good enough right now to copy a serious clearance without pen and paper - as my customary practice is to print out Ken's CRAFT form from the fantastic website of his. This troubles me for RW flying as I try to eliminate paper...

Peter and Ryan B - I do enjoy looking behind the ATC curtain and seeing the plethora of details and minutia you gentlemen have to master.

Thanks for the feedback. Looking forward to the next set of approaches!

Todd

[stevekirks]

The solution - the wonderful circling to land option - fly the approach to one runway then visually orbit the field to land on another runway. It can get you into trouble or it can save you. I knew the wx was pretty good so I was comfortable circling even at night/dusk even at min altitude (below Traffic Pattern Altitude). All legal.

That's the part I'm not sure of from a training standpoint. In the real world, it would seem that you would be expected to terminate the approach by landing or going missed. Maybe once you were visual on final and with tower, you could request to enter the pattern. If the winds weren't right, then real world, you would have been denied the approach and give something for runway 26.

Overall, with the busy world of SoCal, it doesn't seem you would have been able to get yourself into this situation. Clearance delivery would have forced the TEC route, SoCal approach would have denied your request for the approach procedure and vectored you to the IAF of one of the GPS rwy 26 versions.

What does everyone think?

[Keith Smith]

Todd,

You're calling it a 'hold', and are implying there's might be ambiguity regarding the NoPT. In fact, it's a Hold In Lieu of Procedure Turn (HILPT). As the name implies, it is used in place of a procedure turn, so the NoPT label applies equally.

This approach is as standard as it gets for RNAV, with an IAF leading to an IF.