Visual Approach
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CR, I'm still a little confused - which is not good, as I should know this stuff. I refer specifically to your comment "But there's a little bit more to say about that - when cleared visual approach, your previous level requirement of 2000 is removed, and you can in fact descend IAW DME/GPS arrival steps."
We're talking about operations in CTA here - obviously OCTA you can descend on the DGA profile and when you're within the circling area, conduct the approach to landing as required. In CTA though, I thought descent below the last assigned altitude (in this case 2000) was not permitted until within the circling area - the level requirement is not actually removed. I've re-read the law as posted by Renurpp on the previous page:
11.6.5 Minimum Altitude Requirements. During the conduct of a visual
approach, a pilot must descend as necessary to:
b. by night:
(1) for an IFR flight:
− maintain an altitude not less than the route segment
LSALT/MSA or the appropriate step of the DME/
GPS Arrival procedure, or 500FT above the lower
limit of the CTA, if this is higher; or
− if receiving an ATS surveillance service, operate not
below the last assigned altitude;
until the aircraft is:
− within the prescribed circling area for the category
of aircraft or a higher category, where the limitations
of the higher category are complied with, and the
aerodrome is in sight; or
And the rest applies when you're aligned with the centreline, which we're not. So if we're receiving an ATS surveillance service, we can't operate below the last assigned altitude (2000) until within the prescribed circling area. Which I read as saying that although it'd be perfectly safe with regard to terrain clearance, descent on the DGA steps below the last assigned altitude is not permitted until within the circling area.
Sorry if missed something completely obvious here.
We're talking about operations in CTA here - obviously OCTA you can descend on the DGA profile and when you're within the circling area, conduct the approach to landing as required. In CTA though, I thought descent below the last assigned altitude (in this case 2000) was not permitted until within the circling area - the level requirement is not actually removed. I've re-read the law as posted by Renurpp on the previous page:
11.6.5 Minimum Altitude Requirements. During the conduct of a visual
approach, a pilot must descend as necessary to:
b. by night:
(1) for an IFR flight:
− maintain an altitude not less than the route segment
LSALT/MSA or the appropriate step of the DME/
GPS Arrival procedure, or 500FT above the lower
limit of the CTA, if this is higher; or
− if receiving an ATS surveillance service, operate not
below the last assigned altitude;
until the aircraft is:
− within the prescribed circling area for the category
of aircraft or a higher category, where the limitations
of the higher category are complied with, and the
aerodrome is in sight; or
And the rest applies when you're aligned with the centreline, which we're not. So if we're receiving an ATS surveillance service, we can't operate below the last assigned altitude (2000) until within the prescribed circling area. Which I read as saying that although it'd be perfectly safe with regard to terrain clearance, descent on the DGA steps below the last assigned altitude is not permitted until within the circling area.
Sorry if missed something completely obvious here.
It may well have been.
He does mention it has happened a couple of times, and although the rules are fairly straight foward there maybe other options depending on where the situation occurs.
He does mention it has happened a couple of times, and although the rules are fairly straight foward there maybe other options depending on where the situation occurs.
As i have been put in this situation a couple of times at a controlled aerodrome, where they have cleared me to the VOR and then at 20ish miles said "cleared visual approach"... I know that the final/localiser is just there...
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So Renurpp, is that your interpretation of the rules? That at a controlled aerodrome, when cleared visual approach and not established on centreline/slope, you cannot descend below the last assigned altitude (2000 in the example) until within the circling area, regardless of DGA procedures applicable to the aerodrome? Or is there an instance where you can legally descend below 2000 outside the circling area when not established on centreline/PAPI/etc., when cleared visual approach?
My interpretation, as above, is that although you may be assured of terrain clearance by flying the DGA steps, you cannot legally descend below your assigned altitude until within the circling area - i.e. being cleared visual approach does not remove the level requirement of 2000 beyond the circling area (unless established on final as per the rules).
My interpretation, as above, is that although you may be assured of terrain clearance by flying the DGA steps, you cannot legally descend below your assigned altitude until within the circling area - i.e. being cleared visual approach does not remove the level requirement of 2000 beyond the circling area (unless established on final as per the rules).
RENURPP,
How about in a non-radar CTA?
How about in a non-radar CTA?
Its a huge concern, although not supprising, the number of posters not aware of the requirements of a visual app. Geez this is bread and butter stuff.
Its not a very steep descent unless you want it to be.
In the question given, you are not on the centrelines of any runway, so you do need to wait until you are in the circling area before you descend.
Descend in a holding pattern if you want to preserve your passengers' ears. It is a circling area: so circle!
In the question given, you are not on the centrelines of any runway, so you do need to wait until you are in the circling area before you descend.
Descend in a holding pattern if you want to preserve your passengers' ears. It is a circling area: so circle!
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ZappBrannigan,
Excellent post - from the point of view of throwing in something about which, it would appear, none of us are too sure. The spanner you have thrown in, as you are aware, is this part:
So what, exactly is an "ATS surveillance service"? I have been doing some research on that question this morning. At first, it would appear that just being radar identified constitutes being under an "ATS surveillance service".
But, from looking at an old copy of the AIP book, it appears that "being radar vectored" is what it actually means. And this would make perfect sense, as, if being radar vectored, then the controller should have the responsibility for terrain clearance (and getting the aircraft down to the MVA (minimum vectoring altitude)).
And, the descent to the MVA should be the last instruction to the pilot before the "cleared visual approach" (when being radar vectored). (I came across this statement somewhere during my research.)
Here is the same passage, quoted from my old AIP book (page ENR 1.1-23, para 11.5.5 b. (1). The page is dated 24 NOV 2005):
for an IFR flight:
- maintain an altitude not less than the route segment LSALT/MSA or the appropriate step of the DME/GPS Arrival procedure, or 500FT above the lower limit of the CTA, if this is higher; or
- if being radar vectored, operate not below the last assigned altitude;
until the aircraft is: ...
So, it would appear that, for an arrival in CTA when radar vectoring has not commenced, Counter-rotation is correct in his statement that the visual approach clearance constitutes clearance to descend below an assigned level.
It was my understanding, also, that this descent authorisation was implicit in the visual approach clearance.
Excellent post - from the point of view of throwing in something about which, it would appear, none of us are too sure. The spanner you have thrown in, as you are aware, is this part:
− if receiving an ATS surveillance service, operate not
below the last assigned altitude;
below the last assigned altitude;
But, from looking at an old copy of the AIP book, it appears that "being radar vectored" is what it actually means. And this would make perfect sense, as, if being radar vectored, then the controller should have the responsibility for terrain clearance (and getting the aircraft down to the MVA (minimum vectoring altitude)).
And, the descent to the MVA should be the last instruction to the pilot before the "cleared visual approach" (when being radar vectored). (I came across this statement somewhere during my research.)
Here is the same passage, quoted from my old AIP book (page ENR 1.1-23, para 11.5.5 b. (1). The page is dated 24 NOV 2005):
for an IFR flight:
- maintain an altitude not less than the route segment LSALT/MSA or the appropriate step of the DME/GPS Arrival procedure, or 500FT above the lower limit of the CTA, if this is higher; or
- if being radar vectored, operate not below the last assigned altitude;
until the aircraft is: ...
So, it would appear that, for an arrival in CTA when radar vectoring has not commenced, Counter-rotation is correct in his statement that the visual approach clearance constitutes clearance to descend below an assigned level.
It was my understanding, also, that this descent authorisation was implicit in the visual approach clearance.
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So what, exactly is an "ATS surveillance service"? I have been doing some research on that question this morning. At first, it would appear that just being radar identified constitutes being under an "ATS surveillance service".
Para 1.9.5.1 (Jepps) of the relevant section says as an IFR flight at night you can be given a visual approach clearance within 30nm OR when receiving an ATS surv. service, have been assigned the MVA and given heading/tracking instructions to intercept final or place the aircraft within the circling area.
So I still believe if you're given an assigned altitude, cleared visual approach and given no further clearances or instructions, you cannot descend below that assigned altitude (whether it happens to be the MVA or not) until within the circling area, regardless of DGA procedures etc.
Of course, this doesn't stop you requesting further descent on the DGA profile, or tracking to intercept final etc. as discussed earlier - but the issue here is whether you can descend below last assigned altitude at a Class C aerodrome before the circling area - and I don't believe you can.
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Just to add my two cents.
When i fly into townsville at night i often get the following:
"Descend and maintain 1900ft, when in the circling area, cleared visual approach runway 07"
This is how I thought it was supposed to work.
When i fly into townsville at night i often get the following:
"Descend and maintain 1900ft, when in the circling area, cleared visual approach runway 07"
This is how I thought it was supposed to work.
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Av8tr, sounds spot on. They clear you to the MVA (1900'), and you're only permitted to descend below this in the circling area.
If the visual approach clearance removed the altitude restriction, then there'd be no need for the clearance to 1900'.
If the visual approach clearance removed the altitude restriction, then there'd be no need for the clearance to 1900'.
G'day Zapp, and sorry for so long in responding...
Yeah, I must say it seems far from obvious. Maybe I am actually recalling from earlier days (I have a few grey hairs) when it used to say "radar vectors" - as pointed out by FGD135. This "ATC surveillance service" bizzo definitely leaves me a bit cold...
I still stand by my belief though, that once you are cleared for a visual approach, your altitude restrictions are as I stated earlier, ie. unless you are on a vector, you have the option to descend IAW... (all that DGA step / MSA / lower CTA limit stuff) If you've been given a vector and a level, maintain that level until in the circling area OR you intercept final (where VASIS / PAPI / ILS GP all come into things...) Remember you may be given a vector to intercept, say, a 5 or 8 mile final - well outside most circling areas, and at 5 miles a normal 3 degree approach has you at 1500ish feet AGL. 8 miles is 2400ish AGL.
Where I fly, we almost always get progressive descent, tracking inbound to the aid, with the last assigned level being 3000. Soon after that, I usualy can and do tell them I'm visual (otherwise it would be IAFs and a whole other discussion). Inbound track is often very close to a straight in approach too, so it is quite similar to the original poster's hypothetical. OK so I tell 'em "visual" (at about 15nm), and get "cleared visual approach"... I don't want to be at 3000 (my last assigned level) on a 2.66 (Cat B) final, so I use the DGA steps to allow further descent, and once in the circling area, I can commence manoeuvering somewhat as required to gain the centre line, and continue on the PAPI. If I want to manoeuver earlier, I ask for it ie. request direct to 5 nm final, from present position - otherwise my tracking is restricted to as previously cleared, regardless of the subsequent clearance for visual approach - ie. straight to the aid.
This reminds me a bit of an earlier thread where people were debating whether "cleared visual approach" required a readback - based on whether it was in fact a clearance, or a statement removing a previous restriction / limitation. Sounds pedantic, but there were some good arguments put forward.
Working from memory (sorry no reference stuff to hand) there is a bit in the Jepp also about criteria for when ATC may authorise a visual approach, and it talks about "the aircraft has been given a vector to intercept final" or something like that... I think?!
The Townsville example offered by av8trflying is just a variation on all of this, in my opinion. 1900 is the last level, and in the same statement the guy is telling you that you are cleared a visual approach once you are in the circling area... You can still ask for something else ie. manoeuvering or what not. The relevance of that to this discussion requires more information. It is very similar to what I used to hear going into Brisbane too.
Last thing, apologies all I tend to be a bit verbose!
But I would rather labour the point a little, than leave out detail which might be important to another's understanding of what I am driving at!
CR.
Yeah, I must say it seems far from obvious. Maybe I am actually recalling from earlier days (I have a few grey hairs) when it used to say "radar vectors" - as pointed out by FGD135. This "ATC surveillance service" bizzo definitely leaves me a bit cold...
I still stand by my belief though, that once you are cleared for a visual approach, your altitude restrictions are as I stated earlier, ie. unless you are on a vector, you have the option to descend IAW... (all that DGA step / MSA / lower CTA limit stuff) If you've been given a vector and a level, maintain that level until in the circling area OR you intercept final (where VASIS / PAPI / ILS GP all come into things...) Remember you may be given a vector to intercept, say, a 5 or 8 mile final - well outside most circling areas, and at 5 miles a normal 3 degree approach has you at 1500ish feet AGL. 8 miles is 2400ish AGL.
Where I fly, we almost always get progressive descent, tracking inbound to the aid, with the last assigned level being 3000. Soon after that, I usualy can and do tell them I'm visual (otherwise it would be IAFs and a whole other discussion). Inbound track is often very close to a straight in approach too, so it is quite similar to the original poster's hypothetical. OK so I tell 'em "visual" (at about 15nm), and get "cleared visual approach"... I don't want to be at 3000 (my last assigned level) on a 2.66 (Cat B) final, so I use the DGA steps to allow further descent, and once in the circling area, I can commence manoeuvering somewhat as required to gain the centre line, and continue on the PAPI. If I want to manoeuver earlier, I ask for it ie. request direct to 5 nm final, from present position - otherwise my tracking is restricted to as previously cleared, regardless of the subsequent clearance for visual approach - ie. straight to the aid.
This reminds me a bit of an earlier thread where people were debating whether "cleared visual approach" required a readback - based on whether it was in fact a clearance, or a statement removing a previous restriction / limitation. Sounds pedantic, but there were some good arguments put forward.
Working from memory (sorry no reference stuff to hand) there is a bit in the Jepp also about criteria for when ATC may authorise a visual approach, and it talks about "the aircraft has been given a vector to intercept final" or something like that... I think?!
The Townsville example offered by av8trflying is just a variation on all of this, in my opinion. 1900 is the last level, and in the same statement the guy is telling you that you are cleared a visual approach once you are in the circling area... You can still ask for something else ie. manoeuvering or what not. The relevance of that to this discussion requires more information. It is very similar to what I used to hear going into Brisbane too.
Last thing, apologies all I tend to be a bit verbose!
But I would rather labour the point a little, than leave out detail which might be important to another's understanding of what I am driving at!CR.
In the Definitions and Abbreviations section, "ATS surveillance service" is defined as "Term used to indicate an air traffic service provided directly by means of an ATS surveillance system" - i.e. the term is not specific to being radar vectored.
When i fly into townsville at night i often get the following:
"Descend and maintain 1900ft, when in the circling area, cleared visual approach runway 07"
"Descend and maintain 1900ft, when in the circling area, cleared visual approach runway 07"
Kind of strange, as they should, according to the rules, be able to clear you the visual approach immediately. This in itself would only allow you to descend once in the circling area. The "once established in the circling area" (as they seem to say it in Melbourne) part of the visual approach clearance is pointless, it would seem.
However, I guess emphasising it in the circumstances the rule applies helps, because once again the rules are so poorly written. It never ceases to amaze me how anal CASA can be in certain areas, yet then leave certain rules and definitions so unclear.
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I thought ATS surveillance was simply RADAR identified (RADAR control - not necessarily RADAR vectors). If you're in RADAR controlled airspace, you have to maintain the last instruction (all of it) until within the circling area, or on the centreline.
Obviously, it would be a lot easier if controllers were more in the habit of saying (at appropriate airports) "descend to [2000], track as required for final, cleared visual approach" !!
Obviously, it would be a lot easier if controllers were more in the habit of saying (at appropriate airports) "descend to [2000], track as required for final, cleared visual approach" !!
Last edited by *Lancer*; 11th May 2009 at 01:08.
It never ceases to amaze me how anal CASA can be in certain areas, yet then leave certain rules and definitions so unclear
"Oh that bag of feckin worms!"
Regards,
BH.
I have to say the Survellance thing is a little confusing. 
Considering the requirements pre the introduction of the Surveillance systems
I would consider the surveillance system to be a "new term" to basically have the same meaning. i.e. if we are operating into a radar environment then we maintain assigned altitude (which should be the MSA/MVA) until we are established in the circling area, or the other options for final.
If that didn't suit, we could always ask to carry out a DME arrival which would basically allow us to do a visual approach as we used to.
glekichi
I don't understand what you are specifically getting at.
If any one can find a definition of ATS Surveillance System I would like to see it.
You would think one of the ATC guys would know exactly what that meant.
Considering the requirements pre the introduction of the Surveillance systems
for an IFR flight:
- maintain an altitude not less than the route segment LSALT/MSA or the appropriate step of the DME/GPS Arrival procedure, or 500FT above the lower limit of the CTA, if this is higher; or
- if being radar vectored, operate not below the last assigned altitude;
until the aircraft is: ...
- maintain an altitude not less than the route segment LSALT/MSA or the appropriate step of the DME/GPS Arrival procedure, or 500FT above the lower limit of the CTA, if this is higher; or
- if being radar vectored, operate not below the last assigned altitude;
until the aircraft is: ...
If that didn't suit, we could always ask to carry out a DME arrival which would basically allow us to do a visual approach as we used to.
glekichi
I don't understand what you are specifically getting at.
How about in a non-radar CTA?
You would think one of the ATC guys would know exactly what that meant.
I suspect "radar vectoring" was changed to "Surveillance service" to cater for ADS-B use by ATC to control the aircraft.
For the same reason, "radar identified" was changed to "identified" some time ago.
Counter-Rotation,
I do not agree. If you are using the DME Arrival steps in anger ie to operate below the MSA at night (it doesn't matter whether you can see the runway or not), then you must do a proper DME Arrival ie FAF at 5nm and straight tracking thereafter until you can satisfy the Visual Approach requirements.
The "Visual Approach" to which you refer only commences when you go eyeballs out: ie in the circling area or on the straight-in Glideslope/VASI as previously mentioned by others.
For the same reason, "radar identified" was changed to "identified" some time ago.
Counter-Rotation,
Ignore anyone babbling about manoeuvering inside 5 miles etc - YOU ARE NOT CONDUCTING THE DGA, just using it to guide further descent during a VISUAL APPROACH - none of the approach speed restrictions apply, and that tracking restriction similarly does not apply.
The "Visual Approach" to which you refer only commences when you go eyeballs out: ie in the circling area or on the straight-in Glideslope/VASI as previously mentioned by others.
Last edited by Capn Bloggs; 11th May 2009 at 02:30.
Hey Bloggs,
I suspect what you say is correct. How ever if we literally take "radar vectoring" to mean the same as "Surveillance service", and are tracking under our own steam then we would not currently be being radar vectored, however we may be under surveillance??
A slight but definite difference.
I take it from the AIP that if we are identified, we cannot descend below last assigned altitude until we are within circling area, established on final etc
It should not be so grey
I suspect what you say is correct. How ever if we literally take "radar vectoring" to mean the same as "Surveillance service", and are tracking under our own steam then we would not currently be being radar vectored, however we may be under surveillance??
A slight but definite difference.
I take it from the AIP that if we are identified, we cannot descend below last assigned altitude until we are within circling area, established on final etc
It should not be so grey
I take it from the AIP that if we are identified, we cannot descend below last assigned altitude until we are within circling area, established on final etc
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Straight from AIP definitions.
ATS Surveillance Service: Term used to indicate an air traffic service
provided directly by means of an ATS surveillance system.
ATS Surveillance System: A generic term meaning variously, ADS-B, PSR,
SSR or any comparable ground-based system that enables the identification
of aircraft.
Basically if you are identified you are in receipt of an ATS Surveillance Service.
ATS Surveillance Service: Term used to indicate an air traffic service
provided directly by means of an ATS surveillance system.
ATS Surveillance System: A generic term meaning variously, ADS-B, PSR,
SSR or any comparable ground-based system that enables the identification
of aircraft.
Basically if you are identified you are in receipt of an ATS Surveillance Service.