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RNAV and visual approach

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RNAV and visual approach

Old 22nd Oct 2018, 19:54
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RNAV and visual approach

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.

Last edited by Lantirn; 22nd Oct 2018 at 20:24.
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Old 22nd Oct 2018, 21:01
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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
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Old 23rd Oct 2018, 01:44
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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'.
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Old 23rd Oct 2018, 05:13
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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?
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Old 23rd Oct 2018, 06:44
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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.

Last edited by 763 jock; 23rd Oct 2018 at 07:03.
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Old 23rd Oct 2018, 08:23
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Originally Posted by 763 jock
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.
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Old 23rd Oct 2018, 08:26
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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.......
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Old 23rd Oct 2018, 11:11
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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.
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Old 23rd Oct 2018, 11:47
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Originally Posted by Capt Scribble
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!!
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Old 23rd Oct 2018, 13:02
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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.
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Old 23rd Oct 2018, 13:49
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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.
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Old 23rd Oct 2018, 13:51
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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.
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Old 23rd Oct 2018, 13:53
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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.
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Old 23rd Oct 2018, 13:54
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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.
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Old 23rd Oct 2018, 14:14
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Originally Posted by 172_driver
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.

Last edited by Lantirn; 24th Oct 2018 at 01:16. Reason: MDH corrected to MDA. Fast typo
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Old 23rd Oct 2018, 15:05
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Originally Posted by Lantirn


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.
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Old 23rd Oct 2018, 15:34
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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.
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Old 23rd Oct 2018, 16:48
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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".

Last edited by m39462; 23rd Oct 2018 at 18:23.
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Old 23rd Oct 2018, 17:43
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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!😜
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Old 23rd Oct 2018, 18:11
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Originally Posted by Lantirn
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.


Originally Posted by Lantirn
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
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