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Leaving a holding pattern

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Old 12th Dec 2010, 09:52
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Quote:
The REUTL FOUR ALPHA is inbound to TGO on R163
which is a 90 degree left turn on reaching TGO. If you're prepared to make a 90 degree turn transitioning at the IAF from STAR to initial approach segment, why wouldn't you make a 154 degree turn from the hold to the initial approach segment?
Good question. Could it be that 90 degrees is the limit?

3 INITIAL APPROACH SEGMENT
3.1 GENERAL
3.1.1 Purpose
3.1.1.1 The initial approach segment begins
at the initial approach fix (IAF) and ends at the intermediate
fix (IF). In the initial approach, the aircraft has
left the en-route structure and is manoeuvring to enter
the intermediate approach segment.

. . . .

3.1.2 Maximum angle of interception of
initial approach segment
Normally track guidance is provided along the initial
approach segment to the IF, with a maximum angle
of interception of:
a. 90° for a precision approach; and
b. 120° for a non-precision approach.

(Doc. 8168)

348 (inbound to IAF) - 254 (outbound after IAF) = 89 degrees.
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Old 12th Dec 2010, 09:57
  #22 (permalink)  
 
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This thread is a little bit like those Bizantin arguments about angel's sex.

First, we have to estate wether we are supposed to be under radar coverage (which is the most likely scenario) or it would be "conventional" ATC.

If in radar control the left turn is probably the thing to do, but better do it considering TGO as a fly by and not as a fly over intersection and fly slow enough so as not to invade the airspace overhead the airfield.

In in conventional control, they should tell you what to do.

As long as you are above the MSA and you don't make an incursion in someone else's path, you can do whatever you want.
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Old 12th Dec 2010, 11:04
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Let's not mix things up, the Standard Instrument Arrival has nothing to do with it:
3.1.2 Maximum angle of interception of
initial approach segment
Normally track guidance is provided along the initial
approach segment to the IF, with a maximum angle
of interception of:
a. 90° for a precision approach; and
b. 120° for a non-precision approach.
This 90/120 deg requirement is for the transition between the initial and intermediate segment. The IF is 11.4 DME TGO on radial 254. Hence the incept angle in this case is 0 degs.

P.s.
Splendid, you are of course right about the radial, don't know what I was thinking when I wrote that
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Old 12th Dec 2010, 11:16
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One more thing. Just one advice for your check, not just relating to this question in paticular. Bear in mind that no checkers knows everything. Just look how different answers you get on this question. (30 deg, 90 deg, whatever you like, can't do it from that holding at all!)

Hence, if the checker is the stubborn and nit-picking type (that at the same time is not aware of the above paragraph), you may do it one way or the other and he will say what you are doing is wrong anyway.

Beware of this kind of personality type. In this case, just have a good explanation ready for what you did if it will ever become an issue. If you show that you thought about what you were doing you might save the check anyway (even if you did it the right way, and he doesn't agree). Big discussions and hitting the checker in the head with the books is not the way forward in a hiring situation. Even if you are right, perhaps he'll get annoyed and fail you on some other mistake that you did, or tell that you have a bad personality.

No normal thinking checker would fail you for turning left or right out of that holding anyway. He is probably more interested in seeing that you are able to make the correct entry. In fact he would probably give you a vector when he feel that he have seen enough holding stuff.

Be consistent, do the same every time. In the unlikely event that you have to exit that holding twice (or any other situation where you are in doubt), do it the same way both times. It's easy to teach you to do something different once you get the job. But if you do thing differently with each maneuver it make you appear that you are uncertain of what you are actually doing.
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Old 12th Dec 2010, 12:15
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All I can find on the subject is this:
1.5.3 Departing the pattern

When clearance is received specifying the time of departure from the holding point, the pilot should adjust the pattern within the limits of the established holding procedure in order to leave the holding point at the time specified.
I could interpret this to back up the right turn view, just keep the turn in the hold going until on a suitable intercept course.

Last edited by Sciolistes; 12th Dec 2010 at 13:12.
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Old 12th Dec 2010, 12:53
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when hold over TGO and cleared for the approach you leave via the fix and then turn preferably right, not left . of course only leave holding when cleared for APP and report "passing fix". turning left would mean a sharp turn . the TGO VOR is pretty close to the airport and you must look not to shoot through the final segment. due to law you left the hold after last time passing the fix and even turning left is nothing wrong as long aircraft performance permits. - you in every case have to position yourself on R254 TGO and follow the published procedure. the second important thing is to keep 5000ft until established on radial and the decend to 4000ft. descend point on final is VATER out of 4000.

but i must say i was x times in EDDS and always had been vectored, never did the standart procedure. what can happen is that radar tells you "cleared for ILS 07, position yourself 10miles final and report established".

when someone can help how to insert a screenshot here i can provide you with the very last ILS 07 chart since i am sitting on a boring standby duty in the crewroom now.
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Old 12th Dec 2010, 13:06
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1.5.3 Departing the pattern

When clearance is received specifying the time of departure from the holding point, the pilot should adjust the pattern within the limits of the established holding procedure in order to leave the holding point at the time specified.
...refers to that you should adjust your timing and inbound turn in the hold to exit the hold over the fix at the cleared time. If you are making one more turn to the right you are still in the holding and are leaving it on the outbound leg.

I guess you could also adjust your timing that it will fit that you can make the turn to the right and then immediately further right that you that you hit the fix again and leave. But what would be gained by that? By making a 360 over the fix, you nose will still be pointed in the wrong direction, and you would have to make a left turn anyway.

If making a right turn and go directly for the radial, without overflying TGO - when and where did you leave the holding?

I'll agree to the fact that it's academical with the procedure in question, due to the similar distance and time to be flow to get established on the 254 radial.
Microburst2002 has the right answer in my opinion:
As long as you are above the MSA and you don't make an incursion in someone else's path, you can do whatever you want.
As an side note I flew the said TGO holding pattern last winter when they were clearing the runway from snow. We left the holding on a radar vector. Only case I can think about where to leave that holding in the without instructions from ATC would be by com failure. In that case I would definitely go for the shortest direction left turn, because it clearly shows ATC without doubt that you are about to leave the holding pattern.
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Old 12th Dec 2010, 13:42
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If you are making one more turn to the right you are still in the holding and are leaving it on the outbound leg.
factually you indeed in the first time do the same you would do still inside the holding , but due to law i think you left tgo holding after passing fix last time and reporting it - the next right turn is then not turning outbound but positioning yourself on the published radial- even when it is here nearly the same manouver as turning outbound.
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Old 12th Dec 2010, 16:08
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Having looked at the approach chart I hereby withdraw my previous answer.
Somehow I got my own drawing wrong.

Using TGO as an IAF, exit the holding via TGO, right turn, intercept Radial 254 outbound.
This keeps you in the protected area, away from the visual circuit (even though you´re at 5000´) and gives you an alignment towards the outbound.

Haven´t flown this one yet, unfortunatly.

Cheers,

Thomas
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Old 14th Dec 2010, 01:13
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Bookworm,
That doesn't seem consistent with what you write above. It is, as you say, just an initial approach segment. Why is there a requirement to "keep your turns on the side of the hold"? After passing TGO inbound for the final time, the hold is irrelevant.
You will have explain where I was inconsistent. Regardless, ICAO says stay within the limits of the pattern. To me that means stay within the pattern as much as possible. In terms of airmanship, given that the hold is designed for 230kts, it is fairly obvious that a 737/A320 turning left would end up over or passing the airfield/approach area, that seems like an odd choice and even may take you outside of the buffer zone.
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Old 24th Dec 2010, 19:47
  #31 (permalink)  
 
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When looking at the chart you could see that the TGO holding is for the missed approach only (dashed line as explained in the legends?? section).

Also, if part of the procedure it would be depicted in the vertical profile of the approach.

When part of the procedure, the holding line would be of the same thickness as the approach track itself.
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Old 25th Dec 2010, 06:37
  #32 (permalink)  
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bookworm:

which is a 90 degree left turn on reaching TGO. If you're prepared to make a 90 degree turn transitioning at the IAF from STAR to initial approach segment, why wouldn't you make a 154 degree turn from the hold to the initial approach segment?
No doubt the TGO hold is not part of the ILS Rwy 07 IAP. It is a general purpose hold, which could be used to absorb an arrival delay for the conventional arrival route over TGO. It is probably more likely used to park a missed approach although it is not a part of the missed approach, per se.

Let's say I am parked there on arrival or after a missed approach and am going to proceed on the south downwind leg for an approach (or another approach after a missed approach hold). This gets into technique as much as procedure since this is not a course reversal hold. What I would do, assuming approach control leaves me to my own devices, when cleared via the south downwind track, I would return to TGO in the hold, then do a right turn around to incercpet the TGO 254 radial (heading 300 would be a good choice), and not leave 5,000 until established on the 254 radial westbound. You will be within the holding pattern protected airspace until you are within the downwind track protected airspace.
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Old 26th Dec 2010, 12:08
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This gets into technique as much as procedure since this is not a course reversal hold.
But doesn't this miss the point a bit? Pilots aren't supposed to have to consider where protected airspace is in deciding which way to turn (granted, it's a useful thing to know about to stay alive, but the system doesn't require it). There are supposed to be only two methods of assuring terrain clearance under IFR. Either:

A) I'm radar identified and either on a vector or on a direct clearance where ATC is assuring the terrain clearance

or

B) I'm following a procedure that has been designed to be safe.

I find it hard to believe that having missed an approach, the only way out of the TGO hold is by radar vectors or an ATC-assured direct. In that case either:

1) It's up to the procedure designer to check that I can make a left turn from TGO with adequate terrain clearance

or

2) It's not up to the procedure designer to check that I can make a left turn from TGO, and the "procedure" requires me to make a right turn of the sort that you describe.

If the procedure requires a right turn, I'd like to see where in PANS-OPS that's described (I'm not challenging you, aterpster). If the procedure allows me to make a left turn, surely the appropriate "technique" is to make a left turn, because it's shorter -- I don't normally make 270 degree turns just for fun.

In this particular case, the MVA in the area of a left turn is only 3500 ft, so it is a terrain-safe manoeuvre. But I don't know if it would be in general.
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Old 26th Dec 2010, 12:23
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By the way EDDM has a similarly oriented hold, inbound axis 082 at MIQ, with a downwind leg of 227 to position for the ILS 08L. But on the AIP chart, there is a dotted line extending east of MIQ on 082, and at a particular DME the dotted track turns left to pass over MIQ again and out on 227.

The dotted line makes an appearance elsewhere where the holding axis and initial segment are significantly misaligned, but apparently not at EDDS.
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Old 26th Dec 2010, 14:35
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bookworm:
 
But doesn't this miss the point a bit? Pilots aren't supposed to have to consider where protected airspace is in deciding which way to turn (granted, it's a useful thing to know about to stay alive, but the system doesn't require it). There are supposed to be only two methods of assuring terrain clearance under IFR.


I don't see that I am missing the point at all. In the context of this thread the point is: how does a pilot get onto the approach from the charted TGO holding pattern without ATC providing radar vectors.?

A) I'm radar identified and either on a vector or on a direct clearance where ATC is assuring the terrain clearance

or

B) I'm following a procedure that has been designed to be safe.

I stated that there is some procedure and some technique aspects. The procedural aspect is that the holding pattern is a right turn holding pattern. The technique part is: what is the point in that right-turn holding pattern where you turn to intercept the TGO 254 radial? Further, there are two procedural minimum altitudes for this transition from the holding pattern to the TGO 254 radial; 5,000 for any portion of the holding pattern and 4,000 once tracking westbound on the TGO 254 radial. The MVA chart has no application whatsoever in this case; in fact, it appears to me that a portion of the holding pattern is in radar airspace of 5,000.

I find it hard to believe that having missed an approach, the only way out of the TGO hold is by radar vectors or an ATC-assured direct.


As well you should find it hard to believe because your premise is incorrect.

1) It's up to the procedure designer to check that I can make a left turn from TGO with adequate terrain clearance


There is no such requirement. The holding pattern is a right-turn pattern and the inbound course of that pattern melds with the centerline of the TGO VOR at the VOR.

At EDDM, the procedure designer did design an alignment turn to depart the holding pattern. This could be because of separation requirements set forth to the designers by Munich ATC; or it could have been a better designer at Munich, or Stuttgart ATC didn't want such a left turn maneuver because it would impinge on critical airspace. we have no way of knowing.


It's not up to the procedure designer to check that I can make a left turn from TGO, and the "procedure" requires me to make a right turn of the sort that you describe.


Repeating myself, it is procedurally a right-turn holding pattern. That means all turns to the right to remain within holding pattern protected airspace.

If the procedure requires a right turn, I'd like to see where in PANS-OPS that's described (I'm not challenging you, aterpster). If the procedure allows me to make a left turn, surely the appropriate "technique" is to make a left turn, because it's shorter -- I don't normally make 270 degree turns just for fun.


Neither PANS-OPS nor TERPS permits a left turn in these circumstances. The technique part is whether you elect to return to first return to TGO to make the requisite right turn, then continuing around to intercept the 254 radial (two separate maneuvers, procedurally), or whether you turn right to intercept while already established outbound in the holding pattern (a more economic maneuver if already outbound when approach clearance is received, rather than returning to TGO.)

In this particular case, the MVA in the area of a left turn is only 3500 ft, so it is a terrain-safe manoeuvre. But I don't know if it would be in general.


The MVA chart is not a pilot navigation chart and, in any case, the MHA is 5,000 and a portion of the pattern is in three different MVA sectors, the highest of which is 5,000.
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Old 26th Dec 2010, 16:02
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Bookworm,
I'd like to see where in PANS-OPS that's described (I'm not challenging you, aterpster).
Where indeed? You know how difficult the relevant documentation is to read, you've commented as such in the past. It is a case of joining the dots. But there are statements relating to hold buffer aeras. My take on these things is that the very mention of which makes it absolutely obvious that the expectation is that aircraft are to remain within.
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Old 27th Dec 2010, 11:28
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I don't see that I am missing the point at all.
I'm sorry, the way I phrased that was unnecessarily confrontational. The point is that a left turn from the inbound to TGO is either protected or not. In your later post, you unequivocally state:

Neither PANS-OPS nor TERPS permits a left turn in these circumstances.
which addresses the question, in this case, quite directly.

But the more general case (and how it applies to this one) is not clear to me. Under what circumstances is a "short" turn from the hold into the initial approach segment not permitted?

Turning to the "technique" aspect:

What I would do, assuming approach control leaves me to my own devices, when cleared via the south downwind track, I would return to TGO in the hold, then do a right turn around to incercpet the TGO 254 radial (heading 300 would be a good choice), and not leave 5,000 until established on the 254 radial westbound.
But hang on a moment, once you pass through the holding axis on a heading of 300, that leaves you at 5000 ft on the wrong (NW) side of the hold tracking up without course guidance to intercept the initial segment. Why is making up that manoeuvre (which is not depicted on the chart) guaranteed to keep you above terrain, while a left turn after TGO is not?

Originally Posted by Sciolistes
My take on [statements relating to hold buffer aeras] is that the very mention of which makes it absolutely obvious that the expectation is that aircraft are to remain within.
Originally Posted by aterpster
The procedural aspect is that the holding pattern is a right turn holding pattern.
But I've left the hold after passing TGO, haven't I?
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Old 27th Dec 2010, 12:52
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bookworm:

But I've left the hold after passing TGO, haven't I?
If you turn left at TGO, you most certainly have departed the holding pattern.
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Old 27th Dec 2010, 12:59
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But I've left the hold after passing TGO, haven't I?
Good question. Your intention is to leave the hold, but you're clearly still in the protected area/buffer zone (whatever it is best called) whilst you turn right. I suppose that technically, during that right turn then you still are in the hold until such time as you have crossed the inbound leg on your way to intercept the intermediate.
But hang on a moment, once you pass through the holding axis on a heading of 300, that leaves you at 5000 ft on the wrong (NW) side of the hold
I think aterpster means that you continue a right turn until a track of 300º is achieved, that would place you in the with hold pattern area for most of the manoeuvre and WSW of TGO.
Why is making up that manoeuvre (which is not depicted on the chart) guaranteed to keep you above terrain, while a left turn after TGO is not?
It seems to me that turning left would probably take you 4nm away from TGO over the runway and short final and over the 2,000' spots for the intermediate intercepts. Conversely turning right should keep you with the 1000' clearance buffer zone of the hold and within 5º of the intermediate (or much closer and for much longer than a left turn) and away from the 2,000' spots.
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Old 27th Dec 2010, 18:09
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I think aterpster means that you continue a right turn until a track of 300º is achieved, that would place you in the with hold pattern area for most of the manoeuvre and WSW of TGO.
For "most" of it, yes. But you cross the axis and move to unprotected side before intercepting the 254 radial. So there's no more guarantee of terrain clearance than there is with a left turn from TGO. In practice, of course, there is terrain clearance in both cases, but as aterpster says, the pilot shouldn't use the MVA chart to make decisions about the correct procedure.

It seems to me that turning left would probably take you 4nm away from TGO over the runway and short final and over the 2,000' spots for the intermediate intercepts. Conversely turning right should keep you with the 1000' clearance buffer zone of the hold and within 5º of the intermediate (or much closer and for much longer than a left turn) and away from the 2,000' spots.
In practice, in this particular case, it does look as if a left turn takes you close to the airfield, but that should be no more a consideration in which way to turn in a charted procedure than the MVA chart. In practice the controller will be vectoring you, or, more likely these days, telling you to fly to DS430!

I'm sorry for labouring this one, but it does seem that there's still an ambiguity. If I'm inbound on track 343 to TGO on the REUTL4A arrival and cleared for the approach with no mention of the hold, surely I'm supposed to make a 90 degree left turn on to 254, and the procedure designer is supposed to check that I can do so safely, because it's part of the classic arrival-approach depicted in PANS-OPS fig I-4-1-1 "Segments of instrument approach". But because there's a hold depicted there turning left from the inbound leg is suddenly unprotected?!

What about the other IAF, LBU? That's a left-hand hold, inbound on 178, with the initial approach segment on the 233 radial. That's a 55 degree right turn. Leaving that hold, am I really supposed to turn 305 degrees left (or more likely 330 with an intercept)?
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