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greg765
1st Nov 2019, 18:34
Hi guys,

I have some doubts about how to fly properly a full procedure with a racetrack such as the one depicted on the attached plate.

It's been a long time I haven't flown a full procedure racetrack and now I have a doubt...

I prefer not to influence the answers, so for now I will not specify what my exact interrogation is, but I would like to know how you would fly it to see if it matches what I would do.

Let's take two scenarios:
1 - You are coming from the north tracking "southbound" towards the OEM NDB. Let's say that you are not on the dotted line but within 30° in track from the FAT of 183°. ATC clears you for the full approach, what do you do ?
2 - You are now coming from the south tracking "northbound" towards the NDB, so well outside from the 30° arrival sector. Again, ATC clears you for the full procedure approach. How do you fly it ?

Actually I am going to say what I would do in this spoiler section...But I may be wrong !
Scenario 1 : Being within 30° of the FAT, I would just shoot the approach without entering the racetrack or the holding pattern (provided the altitude allow it of course). So basically it would be a straight in approach (I would only overfly the NDB once).
Scenario 2 : Being outside the 30°, I would need to reverse my course. I would enter the racetrack (entry like for an holding pattern), fly the racetrack and finally descend with the approach (so I would overfly the NDB twice in total). I would not use the holding pattern, only the racetrack.

Am I right ? Am I wrong ?

Thanks !


Thank you !

Check Airman
1st Nov 2019, 22:14
Under US rules, regardless of where you’re coming from on that approach, unless you’re cleared for a straight-in approach, you have to do the course reversal. No matter how illogical it may seem...

Tomaski
2nd Nov 2019, 02:30
Keep in mind that for some of these procedures, the racetrack is for descending to the FAF altitude as well as aligning with the final approach course. You could be perfectly aligned but still too high to safely commence the final segment.

Platypus
2nd Nov 2019, 08:34
case 1: I would overfly OEM, start a RT to a heading which is outbound +/- 3xWCA, then at 10DME reintercept inbound track to OEM and commence approach...

case 2: I would cross OEM and fly a parallel entry (as you would do in a holding), do one turn in the race track, and then commence approach.

That‘s what we were taught at our school, and we actually also went to Kristianstad for training once... However, we got vectors to final

a5in_the_sim
2nd Nov 2019, 10:54
Whatever the semantics (right or wrong answer) I would want to make sure ATC’s expectations were consistent with my plans. Modern aircraft flight guidance systems cope well with turning on to tracks well outside the 30 degrees normally regarded as limiting and many operators take a pragmatic view and simply do it to save time. When this becomes a habit at a particular airfield then ATC may wrongly assume that’s your intent as well even when you choose to do otherwise. If in a procedural (non radar) environment this could lead to an inadvertent loss of separation. Even if ATC seem perplexed by your explanation of intent, other aircraft listening in may appreciate the heads up!

Banana Joe
2nd Nov 2019, 11:58
From PANS-OPS Doc 8168 volume 1, Section 4 section 3:

3.2.3.2 Entry into a racetrack procedure
Normally a racetrack procedure is used when aircraft arrive overhead the fix from various directions. In these cases, aircraft are expected to enter the procedure in a manner similar to that prescribed for a holding procedure entry with the following considerations:

offset entry from Sector 2 shall limit the time on the 30° offset track to 1 min 30 s, after which the pilot is expected to turn to a heading parallel to the outbound track for the remainder of the outbound time. If the outbound time is only 1 min, the time on the 30° offset track shall be 1 min also;
parallel entry shall not return directly to the facility without first intercepting the inbound track when proceeding to the final segment of the approach procedure; and
all manoeuvring shall be done in so far as possible on the manoeuvring side of the inbound track.


Note.— Racetrack procedures are used where sufficient distance is not available in a straight segment to accommodate the required loss of altitude and when entry into a reversal procedure is not practical. They may also be specified as alternatives to reversal procedures to increase operational flexibility (in this case, they are not necessarily published separately).

So in case one, I would request a straight in approach if altitude permits it.

Banana Joe
2nd Nov 2019, 12:24
I think he meant the outbound heading would be corrected by three times the WCA applied on the inbound leg, but that might not be correct if you overfly OEM not coming from the inbound track.

Empty Cruise
2nd Nov 2019, 13:11
Coming from the N - easiest option would be clearance to establish for a straight-in, intercepting the final outside 13DME. As the Initial Approach Altitude is above the MSA, you'd be able to descend with the procedure. Otherwise, direct entry from the sector you described, fly the racetrack to 10DME, turn inbound and fly the approach....

aterpster
2nd Nov 2019, 14:30
Scenario 2 : Being outside the 30°, I would need to reverse my course. I would enter the racetrack (entry like for an holding pattern), fly the racetrack and finally descend with the approach (so I would overfly the NDB twice in total). I would not use the holding pattern, only the racetrack.

Thank you !

I thought the 30 degree limit applied only to base-leg entries.

Banana Joe
2nd Nov 2019, 15:00
The entry into the recetrack has to be treated as holding entries with the aforementioned considerations.
In the OP's case two, if coming from sector 2 I would join the racetrack by flying 30° offset for 1 minute and 30 seconds, and if the altitude is good I would shoot the approach.

FlightDetent
2nd Nov 2019, 16:04
I do not really remember seeing what "Full procedure approach" clearance from ATC means. Not PANS-ATS (Doc 4444), nor Annex 10 ICAO.

for A) the procedure has IAF at 13 miles out, +2600. If ATC needs you to racetrack they need to say so, otherwise, all you need to do is stay inside the splay areas and withing assured radio coverage and are free to go. Moreover, from the plan view, the racetrack is not a part of the 13D IAF procedure anyway.

for B) I was trained that if a racetrack is the reversal pattern, joining the shape and establishing inbound is not enough and you must do one full spin after having arrived overhead the fix. A rule I questioned silently but accept, having not taken the time to study in-depth. Lack of authoritative material being a major reason (ICAO / EU rules) [Banana's 3.2.3.2. "2" is a strong hint my gut against the absolute statement might be right]

thread drift: Modern aircraft flight guidance systems cope well with turning on to tracks well outside the 30 degrees normally regarded as limiting and many operators take a pragmatic view and simply do it to save time. When this becomes a habit at a particular airfield then ATC may wrongly assume that’s your intent as well even when you choose to do otherwise. If in a procedural (non-radar) environment this could lead to an inadvertent loss of separation. !!! hear hear!!! Imagine the first non-native, "international" language of ATC being French/Spanish and it gets tough even to explain where you actually are so they can start sorting the mess out. Not funny when it happens.

gearlever
2nd Nov 2019, 16:55
It's ILS / LOC 19.
Not an ADF approach....

SR-22
3rd Nov 2019, 03:54
The +/- 30 degrees is irrelevant to a racetrack. That only applies to a baseturn, 80/260 and 45/180 (the other three reversal procedures).

1. Fly straight to OEM for a direct entry, could descend to MSA before reaching OEM. Once passing OEM you can start descending to the platform altitude of 2500ft and enter the racetrack.
or..
Request to intercept QDM 183 for a straight in approach. You can descend to the IAF altitude once within the 25nm as it's above the MSA.

2. If coming from the south, but east of QDM 003, fly straight to OEM for a teardrop entry, where you can start descending to the platform altitude (2500ft), track 30 degrees off for 60-90 seconds (max 90sec) then turn right and continue outbound track 003 to 10dme, make a right turn and straight in.
If coming in from south, but west of QDM 003, fly straight to OEM for a parallel entry, where you can start descending to the platform altitude (2500ft), track outbound (track 003) parallel to the inbound track to 10dme, turn left to intercept the localiser inbound and go straight in. You cannot go below 2500ft until established inbound on the localiser. Only then can you descend to 2200ft which most likely will be just inside of the IF. You do NOT have to fly the whole circuit in a parallel entry unless being way too high for the final approach segment.

greg765
17th Apr 2020, 13:09
for B) I was trained that if a racetrack is the reversal pattern, joining the shape and establishing inbound is not enough and you must do one full spin after having arrived overhead the fix. A rule I questioned silently but accept, having not taken the time to study in-depth. Lack of authoritative material being a major reason (ICAO / EU rules) [Banana's 3.2.3.2. "2" is a strong hint my gut against the absolute statement might be right]


I remember something similar but I cannot find any official reference to it. Can anybody help with this one ?

The way I understand SR-22 latest message would be that we should join the racetrack, do whatever entry is required depending on the entry sector, and shoot the approach straight away (if altitude allows). But it makes a huge difference if I have to enter the racetrack, then fly over the beacon again without shooting the approach, fly a full racetrack before I can shoot the approach.

How many times are we supposed to overfly the beacon ? (Haha I know, a straight in approach would be much easier, but that's not the purpose of the question ;) )

aterpster
17th Apr 2020, 13:45
Under US rules, regardless of where you’re coming from on that approach, unless you’re cleared for a straight-in approach, you have to do the course reversal. No matter how illogical it may seem...
To use FAA terms, I would interpret the segment from the north (D 13.0, 2,500 to D 9.3) to be "NoPT." The fact it is an initial approach segment from an IAF to IF tells me that.

Check Airman
17th Apr 2020, 17:34
To use FAA terms, I would interpret the segment from the north (D 13.0, 2,500 to D 9.3) to be "NoPT." The fact it is an initial approach segment from an IAF to IF tells me that.

I’ll tread lightly, as I’m taking a knife to a gunfight, but wouldn’t the NO PT technically have to be published? I agree with your logic that if you’re following through from the IAF to IF you shouldn’t need it, but can’t remember seeing that written anywhere.

aterpster
18th Apr 2020, 00:24
I’ll tread lightly, as I’m taking a knife to a gunfight, but wouldn’t the NO PT technically have to be published? I agree with your logic that if you’re following through from the IAF to IF you shouldn’t need it, but can’t remember seeing that written anywhere.

ICAO PANS-OPS doesn't have "NoPT." That is an FAA term. Then again, at the airport in question, MSAs are operational altitudes. Plus, the airport has two LPV IAPs with TAAs for reference (I know, that is cheating).