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Lantirn
22nd Oct 2018, 20:54
This question is for pilots but also ATCO's could help alot.

We were flying to Corfu (CFU) airport. While enroute looking the metar there the wind was blowing gusts of 30 knots from the south, so we had to plan for runway 17.

They have procedures for runway 35, such as VOR W 35 which is one of the most commonly used, but no procedure for 17. For 17 the ATC uses LCTR A circling procedure which is again an offset approach, but from the south like the others.

The minima are another story. VOR W 35 procedure has 2000ft minimums with 2000ft for circling. LCTR A has 1700ft circling only minima as it is an offset procedure. RNAV 35 (LNAV only) has 770ft minumums.

Since the weather there has regularly low cloud, we planned to execute RNAV runway 35, to break the clouds and then enter visual east downwind for runway 17.

But the controller didnt allow us to fly because RNAV 35 procedure does not have published circling minima. Well that was ackward, because we were not asking to circle, but to execute visual approach if we were to see the whole area below clouds, which is another story.

Anyway we were not planning to go very low, but something like 1500ft or 1200ft in worst case scenario, and then get the visual to fly the visual pattern, which is way lower than the 2000ft or 1700ft minima.

Finally we flew straight in RNAV 35 since the wind was from east and landed with 4 knots tailwind component.

In a discussion after landing with the TWR they said that they do not allow this since RNAV 35 doesnt qualify for circling minima. We said that we didnt want to fly circling approach, but a visual approach. What they said is that they handle both the same way since both are visual approaches. This is just ridiculous, it makes no sense, how a circling approach is the same as a visual approach? How they allow visual approaches from VOR W 35 to enter left hand downwind runway 17, down to traffic pattern altitude below circling minimums? Theoretically its the same path.

So, it is allowed to break an RNAV and fly a visual approach? In my opinion you can break any procedure and fly visualy, if patterns are not prohibited from this side of course. I cant find anything usefull in my books. Also some RNAV visual approaches are used throughout the world, but this is also another type of procedure.

Really interested in the technical aspect!

Please any thoughts about this, any opinions are welcomed.

Cyclone733
22nd Oct 2018, 22:01
Hi Lantirn,
My understanding of the term 'Circling' is the visual part of an approach to a runway after you've broken off from the instrument part of the approach. The controller's 'Circling' is in effect your 'Visual approach'
EASA Annex 1 - Definitions States " ‘Circling’ means the visual phase of an instrument approach to bring an aircraft into position for landing on a runway/FATO that is not suitably located for a straight-in approach"

The EASA documents go into some depth on the way circling minima are calculated. One of the take home points is that the minima for circling can't be lower than the minima for the instrument approach it's based on.
So for the VOR35 I'd imagine the hills to the West of the approach are a factor in the higher than normal minimums
I don't know why the RNAV35 doesn't include a Circling minima as well.
My guesses would be:
1. Cost/Time in calculating the minima
2. Higher minima for circling due to the approach path being closer to the hills to the South of the field
3. An interim procedure to be replaced with future LNAV/VNAV to 17 or RNP-A approaches
4. Issues with any go around due to terrain and airspace issues (the high ground to the North and close proximity to another FIR)

Question for you, if you weren't intending to 'Circle' how were you intending to fly the visual approach?

All the best

rak64
23rd Oct 2018, 02:44
Are you talking about Kerkia? It is an old airport with a challenging approach, fitted between the coast and the city of Kerkia. The local staff is amiable, doing all possible what the small apron could give esp. during the busy summer period.There is not only a 1500 feet hill direct left of the approach 35, north of the airport is another huge mountain with MSA of 5300 feet. Additionally is the boundary to Albania about 4 NM northeast of ref point. During approaching for RWY 17, it is easy to enter the Tirana FIR, what is to my knowledge not coordinated by the controller. As advise, if in doubt get the AIP documents for that airport. The controller for that airport has more regulations to follow than Jeppesen can indicate. Thatswhy always follow the controller.Jeppsen shows no approach for RWY 17. The only hint is on the plate for VOR W, say; not west of the airport and MDA 2000'.

FlyingStone
23rd Oct 2018, 06:13
Circling minima are there for a reason. If you have commenced (i.e. crossed the FAF) an instrument spproach procedure, you can’t just “break off” and do a visual approach to another runway. This is called a circling approach and certain rules are required to be adhered to.

Just a hypothetical question... How low were you willing to go on the RNAV approach before you would have to have the runway in sight for the visual approach?

763 jock
23rd Oct 2018, 07:44
The LIDO chart is quite clear on this. The RNAV 35 specifically prohibits circling. The minimums are there for a reason.

My operator had a very serious event at CFU with somebody attempting a low level visual circuit. Much easier to follow the rules. They are for your benefit.

It is also worth reviewing the required visibility and distance/heights required clear of cloud in order to be able to carry out a visual approach.

gravityf1ghter
23rd Oct 2018, 09:23
The LIDO chart is quite clear on this. The RNAV 35 specifically prohibits circling. The minimums are there for a reason.

My operator had a very serious event at CFU with somebody attempting a low level visual circuit. Much easier to follow the rules. They are for your benefit.

It is also worth reviewing the required visibility and distance/heights required clear of cloud in order to be able to carry out a visual approach.

Exactly this. If youíre trying to think of a way around the rules, have a think about what youíre doing.

Look at at the options you have, assess each one on there merits, donít start inventing your own.

RVF750
23rd Oct 2018, 09:26
I concur with previous replies. If you don't know the difference, or are not familiar with Kerkia, then stay away from it. The Hills and wind affects from them can be challenging. Our company dictates a visit in daylight before a night arrival, strict adherance to procedures as it is most definitely a CAT C aerodrome. Once you go on a nice clear day, the terrain is obvious.

It's most certainly not a place to much about at low level.......

Capt Scribble
23rd Oct 2018, 12:11
If you find VFR conditions on the approach and they exist to touchdown, you would be free to ask the controller for a visual approach. A circling approach can normally be flown with a lower cloudbase and so long as you can keep the touchdown point visual you can continue without VFR conditions.

LeadSled
23rd Oct 2018, 12:47
If you find VFR conditions on the approach and they exist to touchdown, you would be free to ask the controller for a visual approach. A circling approach can normally be flown with a lower cloudbase and so long as you can keep the touchdown point visual you can continue without VFR conditions.

Folks,
Captain Scribble is on the right track.
Visual circling is the visual segment of a non-precision instrument approach.
A VISUAL APPROACH is NOT the same, and the rules for a visual approach vary somewhat from state to state. A VISUAL Approach might require a circuit, which is NOT circling.
Make certain you know the difference, the ceiling and visibility required for a visual approach will be (generally) much higher than for a circling minima, and if an instrument approach (of any kind) has no minima for same, can't be done ---- but that does not preclude visual approach, having abandoned, with ATC clearance, the instrument approach.
Make very very certain you understand the definitions, difference and the local rules.
Tootle pip!!

Lantirn
23rd Oct 2018, 14:02
It seems I found references guys, will copy copy/paste them here, it seems we were right.

But first of all I would like to share that in my company visual approaches are allowed both day and night, plus we didn’t want to fly anything illegal, neither do something unsafe. My question was regarding the legality of the decision.

So here we are:

Circling approach definition (ICAO PANS-OPS doc 7168)

Circling approach. An extension of an instrument approach procedure which provides for visual circling of the aerodrome prior to landing.

Visual approach definition (ICAO ATM manual doc 4444)

Visual approach. An approach by an IFR flight when either part or all of an instrument approach procedure is not completed and the approach is executed in visual reference to terrain.

6.5.3 Visual approach LIDO users look General 1.6.4.1.8

6.5.3.1 Subject to the conditions in 6.5.3.3, clearance for an IFR flight to execute a visual approach may be requested by a flight crew or initiated by the controller. In the latter case, the concurrence of the flight crew shall be required.

6.5.3.2 Controllers shall exercise caution in initiating a visual approach when there is reason to believe that the flight crew concerned is not familiar with the aerodrome and its surrounding terrain. Controllers should also take into consideration the prevailing traffic and meteorological conditions when initiating visual approaches.

6.5.3.3 An IFR flight may be cleared to execute a visual approach provided the pilot can maintain visual reference to the terrain and:

a) the reported ceiling is at or above the approved initial approach level for the aircraft so cleared; or

b) the pilot reports at the initial approach level or at any time during the instrument approach procedure that the meteorological conditions are such that with reasonable assurance a visual approach and landing can be completed


Cyclone733, it seems that a circling and a visual approach are 2 different things in terms of air law. Practically could be the same (but not always), but may not for a pilot, depending on the airport, and with some variability in different flown altitudes.
As for your assumptions about why RNAV 35 doenst have circling is beyond my question, they said that they are going to implement soon RNAV for 17!
Of course we would “circle” the same way as we would fly a close “visual pattern”.

Rak64, yes, Kerkira!

Flyingstone, it seems that 6.5.3.3 b) paragraph sorts it clearly. Yes you can
“break” anytime, even below, assuming the conditions are met.
Of course 6.5.3.2 is a good reason for ATC do deny any visual approach. But i have flown many visual approaches there.

763Jock, LIDO takes minimums from the authorities and fits them there. If they don’t publish circling minima, LIDO will not. But there are circling minima for VOR W 35 as you can see. So there is not something extraordinary to fly a pattern to the east. Nice point through the minima for visual approach, my company has the same criteria with 6.5.3.3 but also RVR has to be not less than 800m. (EASA CAT OP MPA 110) Now that’s very low but should be there for legislative reasons plus the possibility of shallow fog. To fly such a pattern with comfort you need at least 5-6 kilometers of visibility. Check also LIDO General 1.6.8.16 and 1.7.3.5 and don’t confuse VFR minima with Visual approaches, totally different story.

Gravityfighter, sure, that’s why I discuss it. If ATC doesn’t approve it, I cant execute it neither. But my question was towards if my idea had a legal application, and it does. We discussed very politely with ATC later on. But the idea of circling and visual pattern being treated the same by ATC got me surprised. Its not the same thing.

RVF750, yes mate, Greece has many very challenging NPA’s.

Capt Scribble, that’s right.

Leadsled, I don’t know which rules you are referring to, but in Europe you don’t have to keep VMC/VFR minima to execute a visual, however its your responsibility to stay in visual contact and stay out of cloud. Thats how i at least understand it.

FlyingStone
23rd Oct 2018, 14:49
You’ve answered your own question with point 6.5.3.2 as everyone else has tried to explain as well. In my honest opinion, flying a visual approach with ceilings below 1500ft AND below circling MDA is not a very smart idea, especially considering the sorrounding terrain. Take it as you wish.

ATCos have gone to prison in the past for issuing visual approach clearances in less than optimal weather conditions, suggest you read this article (https://www.skybrary.aero/index.php/C550,_vicinity_Cagliari_Sardinia_Italy,_2004).

Sleepybhudda
23rd Oct 2018, 14:51
Excellent own answer Lantirn! Sensible considered opinion backed up with ICAO PANS. Cant fault it. Well okay just make sure Greece has no differences to ICAO filed in their AIP.

Lantirn
23rd Oct 2018, 14:53
Flyingstone, yep, I agree. Itís a good reason to deny a visual approach.

However the the reason of denying a visual because the specific RNAV procedure doesnít have circling minima is at least ridiculous.

Also take a look at circling procedures, at sometime, somehow, when you can maintain runway environment you will have to descend to normal visual altitude, treaffic pattern, say it as you wish.

Starting from a VOR/DME, then circling, when landing at adjacent runway, would will have to get low to 1500ft at least! I donít get why an RNAV instrument procedure wonít allow a visual pattern. Not really valid.

172_driver
23rd Oct 2018, 14:54
If I remember the EASA-OPS rules correctly, and provided they haven't changed, there was only a visibility requirement of 800 meters to conduct a visual. The normal caveat of visual with terrain also applies of course.

That said, in a place like Corfu I would definitely respect the circling minima. There isn't much terrain clearance as it is within the 4,2 nm circle and when you leave MDA there is none. Starting out below MDA cloud scudding. I like the creativeness, but no thanks.

Lantirn
23rd Oct 2018, 15:14
That said, in a place like Corfu I would definitely respect the circling minima. There isn't much terrain clearance as it is within the 4,2 nm circle and when you leave MDA there is none. Starting out below MDA cloud scudding. I like the creativeness, but no thanks.

Well respected reply.

But again, you canít deny a visual pattern because a procedure doesnít have circling minima.

When in visual approach you fly visual.

Circling MDA assumes that you maintain that altitude at weather limiting conditions and that you will descend MDA and break only when you will be visual there.

Here I was talking about a visual pattern from the beginning early in the procedure assuming you have visual contact.

The option not to fly it is a pilots discretion and it is well understood. ATC prohibition is well understood due to weather conditions or other reasons. However ATC prohibition because RNAV doesnít have circling minima is just not valid.

gravityf1ghter
23rd Oct 2018, 16:05
Well respected reply.

But again, you canít deny a visual pattern because a procedure doesnít have circling minima.

When in visual approach you fly visual.

Circling MDH assumes that you maintain that altitude at weather limiting conditions and that you will descend MDH and break only when you will be visual there.

Here I was talking about a visual pattern from the beginning early in the procedure assuming you have visual contact.

The option not to fly it is a pilots discretion and it is well understood. ATC prohibition is well understood due to weather conditions or other reasons. However ATC prohibition because RNAV doesnít have circling minima is just not valid.

Iím curious as to the robustness of being cleared, and then established, on one type of approach (in this case RNAV) and then requesting another approach (in this case visual). Essentially this seems to me like youíre using the benefits of one approach to get to a lower minima, and then asking to change the type of approach onto another, more beneficial one to you, where you can operate outside of the approved minima of the approaches (descending below circling minima).

Whether the approach has circling minima I agree is not relevant as to whether you can fly a visual pattern, but then in my view if you were truly visual in terms of doing the visual pattern, you wouldnít have commenced the RNAV to run into a circling vs visual debate.

None of this is meant in a critical way, simply for conversations sake.

172_driver
23rd Oct 2018, 16:34
Well respected reply.

But again, you can’t deny a visual pattern because a procedure doesn’t have circling minima.

I agree with you that there is some leeway for conducting an instrument approach with a visual break (be it IFR or VFR). It's not an uncommon procedure in the US and have done it myself. But that was iin a Cessna and I was familiar with the area.

Kerkira in a 737 or similar, I am not so sure I'd do it on paper. Though I guess it depends on what you see out window. There and then.

m39462
23rd Oct 2018, 17:48
A picker of nits might focus on when either part or all of an instrument approach procedure is not completed and the approach is executed in visual reference to terrain.
The approach, not some other approach. If you begin an IAP that only serves 35 and end up on 17, you have not executed "the approach".

Paulm1949
23rd Oct 2018, 18:43
Youíre still under IFR flight rules irrespective. Cancel IFR and then you can do your visual approach on any runway. Doubtful however your OMA would allow that though!😜

A Squared
23rd Oct 2018, 19:11
Of course 6.5.3.2 is a good reason for ATC do deny any visual approach.

It looks more like a reason for a controller to not initiate a controller initiated visual. I don't see any reference to denying a pilot requested visual.


but in Europe you donít have to keep VMC/VFR minima to execute a visual, however its your responsibility to stay in visual contact and stay out of cloud.

Really? Hmm that's different. In the US, you must have basic VFR minima (ceiling 1000 ft or higher, and visibility 3 miles or greater) in order to (legally) request a visual

A Squared
23rd Oct 2018, 19:17
ATCos have gone to prison in the past for issuing visual approach clearances in less than optimal weather conditions,

Can you give me an example of a controller who has gone to prison and what specifically the "less than optimal" weather conditions were? In the US, at least, if the reported weather is at least 1000/3sm, and the pilot states that he has the field in sight, the controller can issue a clearance for a visual approach. If the pilot subsequently screws things up, that's on the pilot.

FlyingStone
23rd Oct 2018, 19:35
Night visual turned into CFIT. Read here. (https://skybrary.aero/bookshelf/books/2579.pdf)

As a result visual approaches were forbidden for years at many Italian airport (even in daytime CAVOK).

A Squared
23rd Oct 2018, 19:47
Night visual turned into CFIT. Read here. (https://skybrary.aero/bookshelf/books/2579.pdf)

As a result visual approaches were forbidden for years at many Italian airport (even in daytime CAVOK).


Interesting, thanks for that. I didn't see any mention of the controllers legal woes in that first link you posted, that's why I was wondering. Interesting discussion on the judicial decision regarding what the controller's obligations are. I think If I were an Italian controller, I'd have given my last visual approach clearance, ever, once that came out.

edit: although reading that, it seems to me that it wasn't exactly a case of "less that optimal weather conditions". it's a little vague, but my interpretation was that the weather conditions were fine, it was that because of the aircraft's position, and the intervening terrain, the pilot couldn't have seen the airport from there. And the controller should have known that, somehow.

Jonty
23rd Oct 2018, 19:49
I have no problem with what the OP has tried to do here. Having done visual approaches into CFU myself many times it’s one of those places that as long as you’re sensible it can make the difference between getting in and diverting to Athens.

Think about it in a different way. If you were to commence the RNAV approach to runway 35, and at 1500ft tower report the tailwind is out of limits, yet you are fully visual, and in visual contact with the airport and surrounding terrain, would you do a full go around, missed approach, followed by another approach to the wrong runway, just so you could fly the circle to land? Which is pretty much what you would have done the first time round having broken off from your RNAV to fly a visual circuit to 17. One could argue that going around would be the least safe option, as 2 engine go around a seem to be the most screwed up procedure in the book. You would also save your company over a ton of fuel and about 15 mins of flying.

To my mind, as long as to can satisfy the visual criteria, then a visual approach can be commenced from any part of the instrument approach in use. Indeed we would brief this. If the VOR/ILS/GPS/NDB signal is lost and we are visual we would continue. Also, Larnica has a published RNAV to visual approach.

To me, if there is doubt, there is no doubt. Safety has to be absolutely paramount. However, we also have to practical about what we’re doing.

p.s. Just last month I broke off an ILS in TFS to fly a visual circuit to the other runway. As did about 5 other aircraft.

763 jock
23rd Oct 2018, 21:17
That's common sense Jonty. But forbidden in most airlines these days....

My own outfit prohibits visual approaches at night (1500'agl) but allows a circle to land off any crappy offset NDB approach down to a minimum of 1000' agl.

Rules is rules....

Check Airman
24th Oct 2018, 00:54
That's common sense Jonty. But forbidden in most airlines these days....

My own outfit prohibits visual approaches at night (1500'agl) but allows a circle to land off any crappy offset NDB approach down to a minimum of 1000' agl.

Rules is rules....



No visual approaches at night? That's pretty extreme.

Lantirn
24th Oct 2018, 01:55
Jonty this was my second thought. I tried to be honest with ATC but didnít helped in hindsight.

Next time will do exactly that. When in final he canít deny a visual pattern to the other runway. So if they donít like it in one way, they will like it the other way. You have to be gentle

Crazy, but true. They would accept, I am sure.

As for the legality on the visual patterns, are allowed day and night in my company, no restrictions on circling procedures or wherever.

A squared, yes, in EASA OPS you can check the minimum requirements for visual approach, provided the RVR is more than 800m, and has nothing to do with VFR minima. In USA I know it is done differently. Cheers

Lantirn
24th Oct 2018, 02:36
Iím curious as to the robustness of being cleared, and then established, on one type of approach (in this case RNAV) and then requesting another approach (in this case visual). Essentially this seems to me like youíre using the benefits of one approach to get to a lower minima, and then asking to change the type of approach onto another, more beneficial one to you, where you can operate outside of the approved minima of the approaches (descending below circling minima).

Whether the approach has circling minima I agree is not relevant as to whether you can fly a visual pattern, but then in my view if you were truly visual in terms of doing the visual pattern, you wouldnít have commenced the RNAV to run into a circling vs visual debate.

None of this is meant in a critical way, simply for conversations sake.

Yes of course you benefit of the lower minima to get lower down safely. If by 1500 ft you have everything in sight, I donít see anything wrong here to execute a visual pattern to the other runway. You donít operate outside of the approved minima of the approach when you are visual!
The only common here is the wording ďcircleĒ that confuses many people. Circling minima have other reasons to be there, such as technical reasons, either high terrain not justifying straight in minima or offset procedures, but also practical reasons when you really need to circle in marginal weather, with safe obstacle clearance in a large radius from thresholds and safe escape manueuvering towards the runway during a missed approach, and all of this is called an instrument approach.

But all those above are not required when you fly a visual approach. Because you are not flying any instrument, you just revert to visual.

Of course you can be truly visual when the clouds are OVC016 and you continue a visual pattern. It can make huge difference by hitting TOGA at 2000ft in VOR or 1700ft in LCTR

Everything is TEM management. You give something you take something. 1500ft is not so low. Itís the standard pattern altitude. A visual approach at night with terrain has to be considered and also the familiarity with the airport. Also look at plus points, minus points, sacrifices/benefits of all available resources (like instrument approaches and minimums) and select a course of action. Something working well for someone could feel dangerous for another pilot. Everything is acceptable but we have to be thinking with common sense. Doing this and flying a visual pattern at 800 ft is almost a recipe for a CFIT.

hkgfooey
24th Oct 2018, 06:44
Why not simply ask for radar vectors for downwind 17 which will bring you to the MVA of 2900 ft or fly the LCTR A approach with a CAT C/D circling minma of 1700 ft and then left base for 17. I would see that as better than the RNAV 35 anyway as you join a left downwind with the runway in sight out to the left all times.

AviatorTB
26th Oct 2018, 05:25
Does EASA not have a Contact Approach procedure? It is in 5.4.25 of the AIM but I don't know how to include a link. Candidly, at least one of our controllers here did not know about this...

sonicbum
26th Oct 2018, 09:24
Out of curiosity : is the local Authority considering the implementation of an RNP (AR) approach for Rwy 17 ? I understand that throughout the year the usage ration between runway 35/17 is probably an 80/20 % or so, in that case does it mean it is not worth it ? It it just one of the many examples where an RNP (AR) would be highly beneficial.

172_driver
26th Oct 2018, 14:38
Does EASA not have a Contact Approach procedure? It is in 5.4.25 of the AIM but I don't know how to include a link. Candidly, at least one of our controllers here did not know about this...

No such thing. But in practice it's pretty much what the OP asked to do - clearance for a IAP through the cloud followed by a visual break once in the clear, with obstruction clearance left to himself.

aterpster
26th Oct 2018, 15:13
What's the ICAO ID?

A Squared
26th Oct 2018, 15:19
What's the ICAO ID?

LGKR
.....................

FlyingStone
26th Oct 2018, 17:30
The only common here is the wording ďcircleĒ that confuses many people. Circling minima have other reasons to be there, such as technical reasons, either high terrain not justifying straight in minima or offset procedures, but also practical reasons when you really need to circle in marginal weather, with safe obstacle clearance in a large radius from thresholds and safe escape manueuvering towards the runway during a missed approach, and all of this is called an instrument approach.


This part confuses me a bit. So, circling minima are there for when the weather is marginal, I get that. But when the ceiling is below such MDA (designed for marginal weather), itís fine because you are visual at one point of the straight-in approach?

Why do we even have circling minima then? Why not be practical and every time instead of applying the circling minima, shoot a straight in approach, and ask for a visual once youíre out of the clouds?

Jonty
26th Oct 2018, 17:42
Because circling minima is usually a lot lower than the height a visual circuit would be flown at.

A Squared
26th Oct 2018, 17:46
Because circling minima is usually a lot lower than the height a visual circuit would be flown at.

I don't think you understood the question.

Jonty
26th Oct 2018, 17:48
I don't think you understood the question.

ok, what did you think the question was?

763 jock
27th Oct 2018, 09:09
When you are circling to land you can have the top of the tail in the cloud base at circling altitude. You need the required visibility and be able to keep the runway in site. You must remain within the circling area, 4.2nm for CAT C, 5.28NM for CAT D.

In EASA, to fly a visual approach you need to be VMC. That requires 1000' clear of cloud vertically and 1500M horizontally. A circling approach and a visual approach are fundamentally different.

You can't just fly an instrument approach to one runway (to that approaches minima) then declare "visual" and self manoeuvre to land on the opposite end.

If you took this argument to extremes, you could decide that you'll fly to CAT 1 minima, declare visual at 250' AGL and then call it a visual and fly a low level circuit to the other end.

There is no circling minima on the RNAV 35 procedure. Unless you are able to maintain VMC (as above), the only option is to fly one of the other approaches to its associated circling minima.

Simples.

A Squared
27th Oct 2018, 09:44
In EASA, to fly a visual approach you need to be VMC. That requires 1000' clear of cloud vertically and 1500M horizontally. A circling approach and a visual approach are fundamentally different.

OK, now I'm confused, because up the thread, someone said that a visual was legal as long as the visibility was 800m, with no ceiling requirements. The 800 m and no ceiling requirements sounds more like the US minimums tor a Contact approach, (1/2 SM vis) which is a different animal than a visual approach. which requires 1000 ft sealing and 3 sm vis in the US

Vessbot
27th Oct 2018, 10:02
There is no circling minima on the RNAV 35 procedure. Unless you are able to maintain VMC (as above), the only option is to fly one of the other approaches to its associated circling minima.

Simples.

This isn't the OP's scenario, but for the sake of argument let's say the ceiling was something high like 2500 and you're 1000 below it maintaining required cloud clearance, what's wrong with getting cleared for a visual approach and executing it, regardless of what you were cleared for before? How is that different from the routine multitude of times we are cleared for an IFR procedure and then (partway through it) cleared for a different one?

Edit: come to think of it, this is not a counting the number of angels that can dance on the head of a pin exercise, I've done exactly this in the past. (USA).

sabenaboy
27th Oct 2018, 10:03
Dear Lantirn,

I'm very familiar with CFU airport and I share your feelings. I go there regularly. It's indeed ridiculous that ATC would not allow you to do a visual after breaking clouds on the RNAV35.
Anybody familiar with the airport will know that there are no close in obstacles on downwind or base leg for RWY17. You're flying over the water! So as long as you're VMC below the clouds and have the terrain in sight north and west of the airport, flying the visual approach as you intended is a perfectly safe and sensible thing to do!

763 jock
27th Oct 2018, 10:18
Also very familiar with CFU. Been flying there every Summer for the last 25 years.

I'm not an ATC expert. But the chart says "not authorised" for the RNAV circling. So I would imagine ATC can only offer the RNAV approach when 35 is in use. What you choose to do on the day is up to you. Just don't screw it up if you are bending or flexing the rules.

I've seen at least two careers come to an abrupt end when things went wrong operating outside the rules on "visuals". One involved actual damage, the other very nearly ended up in the water at CFU.

sabenaboy
27th Oct 2018, 11:24
Of course 6.5.3.2 is a good reason for ATC do deny any visual approach. But i have flown many visual approaches there.

6.5.3.2 is only about the case where ATC initiates the visual approach, not when it's the pilot asking for one.
(A Squared already gave that reply in post#20)

Night visual turned into CFIT. Read here. (https://skybrary.aero/bookshelf/books/2579.pdf)
That proves that it's not a good idea to let a civil judge with zero aviation expertise make the judgement in such a case. It's absolutely ridiculous that an ATCO gets blamed for a stupid pilot flying into terrain after requesting and getting a visual approach!
Why not simply ask for radar vectors for downwind 17 which will bring you to the MVA of 2900 ft or fly the LCTR A approach with a CAT C/D circling minma of 1700 ft and then left base for 17. I would see that as better than the RNAV 35 anyway as you join a left downwind with the runway in sight out to the left all times. Because CFU airport often has a thin stratus cloud layer at around 1600' but with great visibilty as soon as you get under it. The OP wouldn't be asking the question if he could see the runway at 2900 ft. :ugh:

TOGA Tap
7th Nov 2018, 08:14
During the circle to land part on an instrument approach pilot must :

1) see the landing runway at at all times during the circle and
2) stay within the prescribed distance radius as per aircraft category.
3) maintain prescribed MDA
4) keep speed bellow max for aircraft category

The combination of MDA, distances and speed during level part of a circling app protects you from all obstacles and terrain.
You are not obliged to see them - you just look for the landing runway - just as you do in a straight in approach.

It is an instrument approach as any other.

Visual approach s quite different - you must see the surrounding terrain and obstacles all the time and be able to safely avoid or overfly them. Speeds and altitudes are up to you.

So the determining factor is the ability to see enough of terrain and obstacles.

Now the question is: can you follow a straight-in segment of a published instrument approach until breaking out of clouds and then require visual approach instead of continuing with circle to land as published?

It is possible providing the pilot can see the terrain and obstacles.

ATC person is not aware how familiar ( or non-familiar ) is the pilot with the surrounding terrain nor what pilot actually sees from the aircraft.

By night with some rain showers acting as curtains terrain and obstacles are simply not visible.

Also Calgari accident shows that the ATC can be found to be partly responsible in case of an accident - depending on what the particular judge thinks about it.

I am not expert for procedure design but I suppose that something in the particular RNAV approach makes circle to land impossible.

So in this situation where there is no published circle to land, wx not ideal, night, foreign crew etc... ATC should be very reluctant to issue a visual approach clearance.

And pilots should not press them for one.

Day time may be different.