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RNAV and visual approach

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RNAV and visual approach

Old 23rd Oct 2018, 18:17
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Originally Posted by FlyingStone
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.
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Old 23rd Oct 2018, 18:35
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Night visual turned into CFIT. Read here.

As a result visual approaches were forbidden for years at many Italian airport (even in daytime CAVOK).
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Old 23rd Oct 2018, 18:47
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Originally Posted by FlyingStone
Night visual turned into CFIT. Read here.

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.
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Old 23rd Oct 2018, 18:49
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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.
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Old 23rd Oct 2018, 20:17
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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....

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Old 23rd Oct 2018, 23:54
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Originally Posted by 763 jock
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.
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Old 24th Oct 2018, 00:55
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Jonty this was my second thought. I tried to be honest with ATC but didn’t helped in hindsight.

Next time will do exactly that. When in final he can’t deny a visual pattern to the other runway. So if they don’t 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

Last edited by Lantirn; 24th Oct 2018 at 01:07.
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Old 24th Oct 2018, 01:36
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Originally Posted by gravityf1ghter


I’m 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 you’re 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 wouldn’t 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 don’t see anything wrong here to execute a visual pattern to the other runway. You don’t operate outside of the approved minima of the approach when you are visual!
The only common here is the wording “circle” 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. It’s 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.
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Old 24th Oct 2018, 05:44
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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.
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Old 26th Oct 2018, 04:25
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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...
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Old 26th Oct 2018, 08:24
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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.
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Old 26th Oct 2018, 13:38
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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.

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Old 26th Oct 2018, 14:13
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What's the ICAO ID?
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Old 26th Oct 2018, 14:19
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Originally Posted by aterpster
What's the ICAO ID?
LGKR
.....................
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Old 26th Oct 2018, 16:30
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Originally Posted by Lantirn
The only common here is the wording “circle” 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), it’s 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 you’re out of the clouds?

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Old 26th Oct 2018, 16:42
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Because circling minima is usually a lot lower than the height a visual circuit would be flown at.
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Old 26th Oct 2018, 16:46
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Originally Posted by Jonty
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.
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Old 26th Oct 2018, 16:48
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Originally Posted by A Squared
I don't think you understood the question.
ok, what did you think the question was?
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Old 27th Oct 2018, 08:09
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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.
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Old 27th Oct 2018, 08:44
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Originally Posted by 763 jock

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
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