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Circling approach for the straight in runway

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Circling approach for the straight in runway

Old 26th Mar 2019, 16:55
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Circling approach for the straight in runway


There was a big discussion several times with friends and colleagues about this scenario:

Hypothetical airport for the sake of conversation OLBA Beirut. Only the KAD VOR is operational and all the ILS’s of the airport are U/S. For the VOR DME 16 2400m vis is required.

Assuming that you are executing the straight in approach VOR DME 16. Due to bad visibility 4000m you don’t see at straight in minimums, so you go around. However at this visibility we know that approaching the runway at circling minimums, as you approach you will see the runway but you would be very high to land straight in. (Hence the old VDP)

So the question arises, is it legal to execute the VOR DME 16, maintain altitude at circling minimums and when visual with the runway, when above the airport at the circling minimums, maneuver the aircraft to position for right hand downwind 16 and land at 16?

Set aside the airmanship which is really obvious that you are taking a big risk doing a circling in these conditions...the conversation is only for the sake of the legality.
Talking about European regulations.

The variability of responses I have received by professionals is tremendous...

I strongly disagree since according to air ops when doing a circling approach you have to have in sight and “maintain”, “at all times” the runway or the runway environment “during the entire circling procedure”. For me this is a recipe for a CFIT

For me is black and white. Flying overhead to position for the downwind you lose the runway once you turn your tail so you are illegal.

Flying an approach, either circling, either straight in is a different cake than the published minimums in the plate. The obvious restriction is that you cannot fly a circling approach when you execute straight in minimums but the opposite is possible, however restrictions apply to remain visual with the runway.

To avoid further unnecessary conversations, “runway environment” is a very specific term, and it does not include known features around such as obstacles, hills, cities, houses, bridges or whatever, unless you are flying circling with prescribed tracks with well defined features.

Would love to listen to you guys


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Old 26th Mar 2019, 19:35
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Originally Posted by Lantirn View Post

There was a big discussion several times with friends and colleagues about this scenario:

Hypothetical airport for the sake of conversation OLBA Beirut. Only the KAD VOR is operational and all the ILS’s of the airport are U/S. For the VOR DME 16 2400m vis is required.

Assuming that you are executing the straight in approach VOR DME 16. Due to bad visibility 4000m you don’t see at straight in minimums, so you go around. However at this visibility we know that approaching the runway at circling minimums, as you approach you will see the runway but you would be very high to land straight in. (Hence the old VDP)

So the question arises, is it legal to execute the VOR DME 16, maintain altitude at circling minimums and when visual with the runway, when above the airport at the circling minimums, maneuver the aircraft to position for right hand downwind 16 and land at 16?

Set aside the airmanship which is really obvious that you are taking a big risk doing a circling in these conditions...the conversation is only for the sake of the legality.
Talking about European regulations.

The variability of responses I have received by professionals is tremendous...

I strongly disagree since according to air ops when doing a circling approach you have to have in sight and “maintain”, “at all times” the runway or the runway environment “during the entire circling procedure”. For me this is a recipe for a CFIT

For me is black and white. Flying overhead to position for the downwind you lose the runway once you turn your tail so you are illegal.

Flying an approach, either circling, either straight in is a different cake than the published minimums in the plate. The obvious restriction is that you cannot fly a circling approach when you execute straight in minimums but the opposite is possible, however restrictions apply to remain visual with the runway.

To avoid further unnecessary conversations, “runway environment” is a very specific term, and it does not include known features around such as obstacles, hills, cities, houses, bridges or whatever, unless you are flying circling with prescribed tracks with well defined features.

Would love to listen to you guys


Hi,

don't have Beirut charts handy but that sounds really really messy. The main purpose of a circling approach is to allow You to land on a runway that has more than 30 degrees offset with the published final approach course, like opposite QFU and/or non opposite runways, for which a straight in IAP is not published. I would just tell to Your peers that the scenario You have described is potentially so unsafe that a deep discussion about legality is completely useless as there is not a single valid reason that would lead You to try and fly this kind of approach, and if You find one, the legal aspect would be the least of my concerns.
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Old 26th Mar 2019, 19:40
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When runway visible sidestep to the right ( upwind leg) and fly a visual pattern staying within the confines of the circling criteria.
And the landing runway may be briefly obstructed by airplane structures.
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Old 26th Mar 2019, 19:43
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Well, I'm not familiar with OLBA, but I looked at the charts.
The VOR DME 16 has straight in minima of 800 ft and circling minima of 1070 ft.The MAP is D3 KAD. There would be nothing wrong with maintaining 1070' until 3DME (= aprox. 1,2 NM before the RWY 16 threshold. ) At D3 KAD, whatever altitude you are at, you MUST start the missed approach.
The charts says that circling is only allowed W and N of AD and only to RWY 03/21, so executing a 'circle to land' to join right hand downwind for rwy 16 over the sea would be illegal.
BUT..., I would think that if, during the missed approach procedure you see the airport, and you request and obtain clearance to perform a visual approach (Don't call it 'circle to land') via right hand downwind over the sea, THAT would be legal.
Easa requires a 800 m RVR for visual approaches, and you must be able to keep visual separation from terrain. (It's not a legal requirement to have the rwy in sight at all times.)
So, yes, I would think it's LEGAL to perform a 'visual approach'. Would it be wise and safe to do it if you wouldn't have the rwy in sight at 800' during a straight in approach?
That's an other question? I wouldn't be trying it, but maybe, just maybe, somebody who is thoroughly familiar with the airport and the obstacles around it could do it safely.
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Old 26th Mar 2019, 21:26
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It's not a legal requirement to have the rwy in sight at all times.)
It is requirement to have the runway environment (features such as the runway threshold or approach lighting aids or other markings identifiable with the runway) in sight at all times. How else would you know where you are, when to turn and descend? It’s also important if you have to manoeuvre for a go around.
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Old 26th Mar 2019, 23:23
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Sabenaboy, well yes OLBA is not a good example. You are right. Disregard the limitations on the circling sectors, it’s my fault on the selection of the airport.
Assume there are no limits on the circling maneuver.

Main question is if you are legal to fly overhead for a circling assuming you haven’t reached the MAP yet. Asking for visual is another option, but the original question is by staying on the circling procedure. Nevertheless, airport environment is again required to continue.

B2N2, that’s tricky to master a CAT C jet in 4000m but I think it’s the only way to do it legally.
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Old 27th Mar 2019, 15:04
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Originally Posted by sonicbum View Post
Hi,

don't have Beirut charts handy but that sounds really really messy. The main purpose of a circling approach is to allow You to land on a runway that has more than 30 degrees offset with the published final approach course, like opposite QFU and/or non opposite runways, for which a straight in IAP is not published. I would just tell to Your peers that the scenario You have described is potentially so unsafe that a deep discussion about legality is completely useless as there is not a single valid reason that would lead You to try and fly this kind of approach, and if You find one, the legal aspect would be the least of my concerns.
What about this approach which has zero offset and no straight-in minimums?



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Old 27th Mar 2019, 15:08
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Main question is if you are legal to fly overhead for a circling assuming you haven’t reached the MAP yet. Asking for visual is another option, but the original question is by staying on the circling procedure. Nevertheless, airport environment is again required to continue.
There is no general prohibition against circling back.

For me is black and white. Flying overhead to position for the downwind you lose the runway once you turn your tail so you are illegal.
For me it is not black and white. I don't see why with 20 - 25° bank you cannot maintain line of sight to the runway environment. To my mind it is legal to circle back. It may not be wise. There is an example in this article at Fig 4.
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Old 27th Mar 2019, 16:21
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Originally Posted by Small cog View Post


It is requirement to have the runway environment (features such as the runway threshold or approach lighting aids or other markings identifiable with the runway) in sight at all times. How else would you know where you are, when to turn and descend? It’s also important if you have to manoeuvre for a go around.
No, you are wrong. According to ICAO and EU ops, It is not a requirement to have the runway environment in sight at all times.

ICAO doc 4444 says:
Originally Posted by ICAO doc4444
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.
EU OPS adopted this in OPS 1.435 by defining a visual approach as
Originally Posted by OPS 1.435
An approach when either part or all of an instrument approach procedure is not completed and the approach is executed with visual reference to the terrain.
While the FAA has adopted an other definition, in most of the world, you can legally ask for and fly a visual approach without having the airport or runway in sight. You could ask for a visual approach (and get it) from 100 miles out, if you know that you will be able to visually find and navigate to the runway.
One example: If the pilot is familiar enough with the airport he could follow visually consecutive landmarks that he knows will bring the airplane on final in a position to land. Or, other example, During 'downwind' the runway might still be obscured by a ridge or hill, but the pilot can still position himself visually around the hill to final.

Don't confuse a visual approach during an IFR flight with a standard visual circuit in VFR!
For EU ops a minimum RVR of 800 m is required.
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Old 27th Mar 2019, 16:41
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Originally Posted by Lantirn View Post
Main question is if you are legal to fly overhead for a circling assuming you haven’t reached the MAP yet. Asking for visual is another option, but the original question is by staying on the circling procedure. Nevertheless, airport environment is again required to continue.


I would think it is legal to do so. I don't consider not being able to see the runway behind you while turning onto downwind as 'losing visual reference'.
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Old 27th Mar 2019, 19:12
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Latirn
if you have had an approach and cannot get the required visual reference at DA/DH for r/w 16 (1.1nm from the threshold), then I think you are unlikely to achieve anything by trying to circle (or visual approach either). There circling procedures that specify that the circling starts at or after passing the r/w threshold. However, those I have flown also require that visual contact with specific landmarks be maintained while turning ‘downwind’ and up until r/w threshold becomes visible again.

Sabenaboy
Your not familiar with OLBA are you? Steep rising ground to the east and south that you don’t want to take liberties with. The OP posed the question that what if the r/w wasn’t seen until starting the go around; vis must be bad eh? Aside the no-no of thinking “it’s a good idea to stop the missed approach and position visually down wind”, just how far will your turn downwind take you from the airfield? If the OP has failed to see the r/w at 788 ft & 1.1 nm, what chance have YOU got by flying a visual circuit. And how would you plan you position your aircraft for base/final? You don’t want to be flying through the c/l at OLBA.

The circling approach is perhaps the most challenging manoeuvre the pilot is asked to fly. Some airlines have even prohibited their crews from flying them. They need to be well planned and brief, not a last minute decision. In the case in question, the usual procedure would be for the right hand seat pilot fly and maintain visual contact. Is your RHS pilot up to speed on flying circling approaches/ visual circuits in poor visibility?

As for scraping around low level in poor visibility over the sea without surface features to aid you to getting where you want to go ... that’s just unprofessional and asking for trouble.

Last edited by Small cog; 27th Mar 2019 at 20:21.
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Old 27th Mar 2019, 19:46
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Originally Posted by aterpster View Post
What about this approach which has zero offset and no straight-in minimums?


That's because of the descent gradient. It's a TERPS thing, don't have the figures handy, but if the descent gradient is more than (400 ?) ft per NM You have only circling minimums. I don't fly a lot in TERPS land so have a look.
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Old 27th Mar 2019, 19:52
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Originally Posted by Small cog View Post

As for scraping around low level in poor visibility over the sea without seurface features to aid you to getting where you want to go ... that’s just unprofessional and asking for trouble.
Exactly... OP forget about asking the legality of turning a straight in into a circling or a visual approach because of weather, it's just a way to understand if You can legally try the EGPWS.
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Old 27th Mar 2019, 20:32
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Originally Posted by Small cog
Latirn
if you have had an approach and cannot get the required visual reference at DA/DH for r/w 16 (1.1nm from the threshold), then I think you are unlikely to achieve anything by trying to circle (or visual approach either). There circling procedures that specify that the circling starts at or after passing the r/w threshold. However, those I have flown also require that visual contact with specific landmarks be maintained while turning ‘downwind’ and up until r/w threshold becomes visible again.

Sabenaboy
Your not familiar with OLBA are you? Steep rising ground to the east and south that you don’t want to take liberties with. The OP posed the question that what if the r/w wasn’t seen until starting the go around; vis must be bad eh? Aside the no-no of thinking “it’s a good idea to stop the missed approach and position visually down wind”, just how far will your turn downwind take you from the airfield? If the OP has failed to see the r/w at 788 ft & 1.1 nm, what chance have YOU got by flying a visual circuit. And how would you plan you position your aircraft for base/final? You don’t want to be flying through the c/l at OLBA.

The circling approach is perhaps the most challenging manoeuvre the pilot is asked to fly. Some airlines have even prohibited their crews from flying them. They need to be well planned and brief, not a last minute decision. In the case in question, the usual procedure would be for the right hand seat pilot fly and maintain visual contact. Is your RHS pilot up to speed on flying circling approaches/ visual circuits in poor visibility?

As for scraping around low level in poor visibility over the sea without seurface features to aid you to getting where you want to go ... that’s just unprofessional and asking for trouble.
Small cog
The OP poster did not ask if it was wise to fly the scenario he was describing, he was asking about legality:
Originally Posted by Lantirn
So the question arises, is it legal to execute the VOR DME 16, maintain altitude at circling minimums and when visual with the runway, when above the airport at the circling minimums, maneuver the aircraft to position for right hand downwind 16 and land at 16?

Set aside the airmanship which is really obvious that you are taking a big risk doing a circling in these conditions...the conversation is only for the sake of the legality.
Talking about European regulations.
And I had already said:
Originally Posted by sabenaboy
Well, I'm not familiar with OLBA, but I looked at the charts.
...
...
It's not a legal requirement to have the rwy in sight at all times
...
...
Easa requires a 800 m RVR for visual approaches, and you must be able to keep visual separation from terrain. (It's not a legal requirement to have the rwy in sight at all times.)
So, yes, I would think it's LEGAL to perform a 'visual approach'. Would it be wise and safe to do it if you wouldn't have the rwy in sight at 800' during a straight in approach?
That's an other question? I wouldn't be trying it, but maybe, just maybe, somebody who is thoroughly familiar with the airport and the obstacles around it could do it safely.
So, I think it's pretty obvious that the OP and myself are well aware of the risks involved in circling or visual approaches in low vis conditions. We are talking about legality here, not airmanship. Why do you find it necessary to start lecturing us about that?
I just reacted to you correcting me for saying that it's not a legal requirement to have the rwy in sight at all times during a visual approach in EASA rules.
I provided proof of what I claimed and you were wrong about that.
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Old 27th Mar 2019, 22:08
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Sabenaboy

In the case of the OP’s scenario he would have made an approach to land so would aircraft have been configured to land. Missed approach requires an early turn during the climb to 2,000ft. While reconfiguring the aircraft and flying the missed approach, you ask to make a visual approach and stop before your below your cleared altitude? During all this you claim to be ‘visual’. Doesn’t sound too well organised to me.

Really? You have briefed for this eventuality? What’s the plan Ace? What’s is your Legal responsiblity when flying visually
Flying visually in the OP’s aircraft ... what speed ... what required visibility? No doubt the Op’s OP’s Manual part C will (should) have something to say on OLBA and what not to do.

Is is it Legal? Perhaps the question should be whether it’s reckless? You say that airmanship wasn’t the question. I’ve known a few people who crashed and died along with their innocent passengers doing some dum flying because it was ’Legal’. No. Airmanship should require a higher standard than ‘just because it’s Legal’. So when the OP enters into discussions about what the situation he should point out that he a sets higher standard and won’t entertain such a stupid idea - Legal or not.



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Old 28th Mar 2019, 03:56
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Thank you for this fine example of preaching to the choir...
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Old 28th Mar 2019, 07:36
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The question was:
So the question arises, is it legal to execute the VOR DME 16, maintain altitude at circling minimums and when visual with the runway, when above the airport at the circling minimums, maneuver the aircraft to position for right hand downwind 16 and land at 16?
No. Having been cleared to fly the procedure, unless otherwise cleared, if not visual by the MAP, you are required to fly the missed approach procedure so as to ensure terrain clearance.

Last edited by Small cog; 28th Mar 2019 at 08:12.
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Old 28th Mar 2019, 08:02
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Not sure if I have missed the point here but I see that in the OLBA example, the viz required for circle to land off VOR DME 16 is 4800m ( and the 1070ft minima you mention) . So, no. , not legal IFR in your declared conditions of 4000m viz. (assuming cat C/D aircraft)
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Old 28th Mar 2019, 09:12
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IFR to VFR



lets agree that circling approach is a continuation of an instrument approach and visual circuits are Visual flights off the instruments and its rules ... whenever IFR pilots like to do visual circuits they should cancel their IFR and declare VMC then if the airports minimums is within VFR limits then he can carry the visual approach either coming overhead to join downwind leg or adjust to join downwind leg and so on ...
for your scenario at OLBA VOR approach MDA is less than circling minima so which is better to fly 800’ or 1100’ ???
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Old 28th Mar 2019, 09:27
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Not sure if I have missed the point here but I see that in the OLBA example
The OP said this:

Sabenaboy, well yes OLBA is not a good example. You are right. Disregard the limitations on the circling sectors, it’s my fault on the selection of the airport.
Assume there are no limits on the circling maneuver. Main question is if you are legal to fly overhead for a circling assuming you haven’t reached the MAP yet
If you read the from the beginning it is clear that he is talking about the general case even though he picked OLBA and came up with a scenario with a vis where you could not even proceed beyond the FAF let alone the MAP.
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