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C.M
4th May 2019, 19:27
There is a certain issue faced on some occasions when given the clearance to follow an approach . As an example pls refer the attached instrument chart

Suppose you are on an arrival route toward waypoint RIMEX by having been cleared to follow a STAR which ends at RIMEX at 4000 ft , and you are given the following clearance “ Bigjet 123 descent to 4000 ft , clear for VOR-DME S rwy 04 .” What would be correct thing to assume ? ( you have been cleared to descent to 4000ft beforehand by following the STAR)

Descent and maintain 4000ft and follow the lateral part of the approach till you are cleared for lower ?
Disregard the fact you were told to descent to 4000ft , from the moment you are cleared for an approach it means follow the procedure both laterally and vertically as published .

mike current
4th May 2019, 23:50
There is a certain issue faced on some occasions when given the clearance to follow an approach . As an example pls refer the attached instrument chart

Suppose you are on an arrival route toward waypoint RIMEX by having been cleared to follow a STAR which ends at RIMEX at 4000 ft , and you are given the following clearance “ Bigjet 123 descent to 4000 ft , clear for VOR-DME S rwy 04 .” What would be correct thing to assume ? ( you have been cleared to descent to 4000ft beforehand by following the STAR)

Descent and maintain 4000ft and follow the lateral part of the approach till you are cleared for lower ?
Disregard the fact you were told to descent to 4000ft , from the moment you are cleared for an approach it means follow the procedure both laterally and vertically as published .


I would expect Bigjet 123 to descend to 4000ft and then to follow the lateral and vertical part of the approach, since they've been cleared for it.

Do you really expect them to be able to complete a successful approach by maintaining 4000ft?

RAC/OPS
5th May 2019, 00:51
Looks like the approach commences at RIMEX so follow that both laterally and vertically.

C.M
5th May 2019, 04:37
Do you really expect them to be able to complete a successful approach by maintaining 4000ft?
If you maintain 4000 after RIMEX you can make a normal approach if you are cleared lower 4 miles after RIMEX. As a matter of fact ( not seen easily on this chart ) the real life approach is coded in the database as a descent from 4000 over RIMEX , to 2000 arriving level at the FAF which is at 6.9 miles from TDN .Anyway mt point is the following . If you have already been cleared to descent to 4000 ft and then the controller repeats “ descent 4000 ft , Clear for the approach “ isn’t the repetition meant as a level restriction , thereby you expect to follow the lateral part till you are cleared for lower ?

poldek77
8th May 2019, 09:01
If you maintain 4000 after RIMEX you can make a normal approach if you are cleared lower 4 miles after RIMEX. As a matter of fact ( not seen easily on this chart ) the real life approach is coded in the database as a descent from 4000 over RIMEX , to 2000 arriving level at the FAF which is at 6.9 miles from TDN .Anyway mt point is the following . If you have already been cleared to descent to 4000 ft and then the controller repeats “ descent 4000 ft , Clear for the approach “ isn’t the repetition meant as a level restriction , thereby you expect to follow the lateral part till you are cleared for lower ?

Looking at the chart I would say that we should pass D13.2 fix at or above 4000' too. Unless this fix is LIDO-produced, not existing in AIP.

Pera
9th May 2019, 01:54
The controller is simply reiterating the starting height for the approach. You are cleared for the approach.

C.M
9th May 2019, 07:34
Looking at the chart I would say that we should pass D13.2 fix at or above 4000' too. Unless this fix is LIDO-produced, not existing in AIP.
it is Indeed a Lido chart. Can you expand on what Lido seems to be systematically doing ?

poldek77
11th May 2019, 06:23
Here you are:

I cannot find AIP chart for this approach (I failed to register to on-line version), but we can compare the LIDO chart with the one published by Jeppesen (by the way the chart that you attached was revised last December).


https://cimg0.ibsrv.net/gimg/pprune.org-vbulletin/2000x1370/lclk_vordme_s_rwy04_lido_6b6c2db5d13e56ef12aadd312e0bed1981e b331b.jpg


https://cimg2.ibsrv.net/gimg/pprune.org-vbulletin/1033x1747/lclk_vordme_s_rwy04_f08874c4fdd380ed91f7fe0310581087678cdd38 .jpg


The LIDO profile has that additional fix – D13.2. It is marked with white letter “D” in a black circle. According to Legend and Tables it depicts descent point for constant descent.

https://cimg9.ibsrv.net/gimg/pprune.org-vbulletin/623x84/lido1_73a2dcac9abf24d9fe3b208f286b906e3f64fdf0.jpg
https://cimg1.ibsrv.net/gimg/pprune.org-vbulletin/624x195/lido2_591ce5d56be0f6e436b85442f70fd7fd3ebf506a.jpg


As I understand such fixes are calculated by LIDO to avoid ‘dive and drive’ approaches. FMS navigation database comes from another provider that’s why these waypoints are not coded in FMS and – as you described - VNAV commands earlier descent, for this approach right after passing RIMEX.

And back to your original question – I agree with the other responders, the phraseology used by ATC is correct, when you are cleared to 4000’ via STAR and for the approach as well you should follow the published profile to be at IAF at or above 4000’ and after RIMEX continue laterally and vertically as charted.
Hope it helps.

Capt Scribble
11th May 2019, 10:36
The grey ‘boxes’ on the Lido vertical profile shows the minimum descent alt if you wish to dive and drive, so you can descend to 2000 after Rimex. I think most operators use constant descent, so the FMGC will have 13.2 coded as the suggested descent point.

OhNoCB
13th May 2019, 00:19
Personally I think LIDO complicate things with their calculated (bold an italics) 'D' point at 13.2 miles. CDFA applies from the FAF, which most know was the Maltese cross point as per the Jepp, which is depicted as the 'F' point on LIDO. Therefore you are not diving and driving by going to 2000' after Rimex. LIDO tries to be overly clever here and confuses things in my opinion. There are some approahces for example which use a 2.8 degree descent, but LIDO will depict a level segment after the FAF and then show a calculated 3 degree one.

poldek77
13th May 2019, 05:27
so the FMGC will have 13.2 coded as the suggested descent point.

Not in my outfit unfortunately

https://cimg4.ibsrv.net/gimg/pprune.org-vbulletin/1200x1600/lclk_vordme_s_rwy04_fms_jpg_3042c59574ac91cfd82abe1abc96a91c 9c6fa9a6.jpeg