Holding Patterns WIP?

[ryanbatc 12,786]

Holding Pattern/Course Reversal/Procedure Turns... are these going to be worked on for SP1? The reason I ask is because I let the A/P fly the ILS Z Ry 08 into KBUR this morning. I arrived at SILEX from LAX318R (so I arrived from the SE). If I were to fly this in real life, it would be direct SILEX, HOLD PARALLEL, then inbound. Granted, there seems to be some debate even in the real world about satisfying the requirements for a course reversal/PT. IRL, per the diagram, my flight path would be the red one, a parallel entry, then intercept the 076 course inbound and continue the approach. The NGX flew the parallel entry, but then entered the complete hold (green line), then proceeded inbound (blue line). This is redundant. What are other people's opinions on this sorta thing. Like I said, I expect pilots do just make one turn, and not enter a full loop, if I'm working traffic. If they need to descend because my MVA is higher than the altitude required in the hold then legally, yes, they can use the hold to get down. We don't have much terrain in Duluth so I don't run into circumstances such as that...

[trisager 2]

Just so I understand - your topic title is "Holding Patterns WIP" - did you program a hold into the CDU, or did you just load the approach, which includes a course reversal? How exactly was the FMC programmed?

[ryanbatc 12,786]

It was programmed by selecting the APP from the list, and then selecting SILEX as the transition. Do I need to manually skip the hold or something after it's flown the parallel entry?

[ZachLW 37]

Correct me if I'm wrong, but I recall that the NGX cannot properly do course reversals (procedure turns and holds in lieu of procedure turns) because of a short coming of the nav database, but this shortcoming was going to be fixed. Again, I could be wrong. EDIT: I think I'm missing the point. The hold is required for course reversal in your presented case, unless otherwise instructed by ATC (ie radar vectors). I'm missing the redundancy, but I'll try harder! Okay, I see your point. I'll try a similar approach.

[ryanbatc 12,786]

But this hold/PT/CR is mandatory, as depicted by the solid oval.

[trisager 2]

Correct me if I'm wrong, but I recall that the NGX cannot properly do course reversals (procedure turns and holds in lieu of procedure turns) because of a short coming of the nav database, but this shortcoming was going to be fixed. Again, I could be wrong. EDIT: I think I'm missing the point.

No, I think you hit the nail. Looking in the navdata I see: TRANSITION SILEX HOLD AT FIX SILEX RIGHT TURN INBOUNDCOURSE 076 ALT 3700 LEGTIME 1This would cause the FMC to make the plane enter the hold and remain there until told to exit. So yes, the workaround would be to exit the hold manually when the course reversal has been flown.

[ZachLW 37]

But this hold/PT/CR is mandatory, as depicted by the solid oval.

Radar vectors override that, I'm sure you're awares.

No, I think you hit the nail. Looking in the navdata I see: TRANSITION SILEX HOLD AT FIX SILEX RIGHT TURN INBOUNDCOURSE 076 ALT 3700 LEGTIME 1This would cause the FMC to make the plane enter the hold and remain there until told to exit. So yes, the workaround would be to exit the hold manually when the course reversal has been flown.

That makes sense, then! Unfortunately I'm not sure what the correct behavior should be in this scenario for the NG's FMC, but manually leaving the hold is barely an inconvenience.

[PIC007 82]

Cancel your clearance Clarence, or have Victor get a vector :-)

[badderjet 181]

The hold is required for course reversal in your presented case, unless otherwise instructed by ATC (ie radar vectors).

Not directly related to the OP, but since I never ran across this case IRL (IIRC), I think I never really understood this concept, could someone plase enlighten me. I know the usual PT, but I never got how a holding would serve as a course reversal and how it would be flown correctly. Do I fly the entry, a holding and then continue (what would I fly the holding for then)? Do I just fly the entry (which would be sufficient as far as reversing the course goes)? Of course ATC could instruct anything, but I'm rather curious about the "standard", theoretical side here.

[ZachLW 37]

Not directly related to the OP, but since I never ran across this case IRL (IIRC), I think I never really understood this concept, could someone plase enlighten me. I know the usual PT, but I never got how a holding would serve as a course reversal and how it would be flown correctly. Do I fly the entry, a holding and then continue (what would I fly the holding for then)? Do I just fly the entry (which would be sufficient as far as reversing the course goes)? Of course ATC could instruct anything, but I'm rather curious about the "standard", theoretical side here.

Good point (which is Ryan's point of contention with the NGX). To reverse course in this instance, one can opt to either do only the entry into the hold or do the full circuit and then start inbound. Both will satisfy "course reversal requirements". I'll refer you to the AIM, but it basically comes down to the given scenario, rather or not you are ready to begin the inbound portion, and lastly rather or not ATC will be ###### you're taking so long to close the flight plan.

[trisager 2]

You just fly the entry - direct or parallel as required - and continue inbound from the fix. You see this type of holding patterns quite a lot instead of procedure turns with RNAV approaches. In this particular procedure the hold over SILEX is also the end of the published missed approach procedure.

[ryanbatc 12,786]

Radar vectors override that, I'm sure you're awares.

But I'm not getting vectors, I came off the LAX316R direct SILEX.

[ZachLW 37]

But I'm not getting vectors, I came off the LAX316R direct SILEX.

I was just clarifying for others that they are not, in all cases, mandatory. I wasn't so much responding to you as much as I was elaborating on your statement. As for the OP. I was under the understanding that yes, this was going to be fixed. I'll find the post. EDIT: http://forum.avsim.n...__fromsearch__1 Unfortunately holds in lieu of a PT aren't mentioned there. Sorry that's about the most I can "contribute". Edited September 1, 2011 by ZachLW

[ryanbatc 12,786]

Perhaps it was in my post where Ryan wrote they were going to have "ARC L" in the FMS etc...

[JC75 22]

Here an interesting one for you to try - delete the hold out and approach out of your FMC - then manually enter the points including the HOLD then BUDDE etc. then fly the route again and see if the NGX then does the correct entry and hold - once it flown around in circles(whereever that may be) select exit HOLD from the FMC HOLD page - Do you get exit armed? does it navigate to next point correctly? does it do the correct join? does it hold in the correct place?