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Circling approach for the straight in runway

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Circling approach for the straight in runway

Old 28th Mar 2019, 09:14
  #21 (permalink)  
 
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Originally Posted by oggers View Post
The OP said this:



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.
Thanks, I did read from the beginning. The OLBA example was held to be bad as the suggested circle to land was not authorised in the circling restrictions. But, my point was, circle to land viz exist for a reason, and in the example given the circle to land viz precluded a circle to land. To answer the general case, one would need to compare the circle to land viz with the actual viz. If we are considering a case where they are equal or not limiting then the answer comes down to the points made, eg obtaining an amended clearance to break off from the missed approach. But, circling minima are higher in general than approach minima for obvious reasons, so its likely that in the general case of a marginal approach viz circling wouldn't be an option.

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Old 28th Mar 2019, 10:42
  #22 (permalink)  
 
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...yes the vis in the scenario was below circling minima as you rightly point out. However, the whole question is moot based on that vis because you are not permitted to continue beyond the FAF anyway with visibility below the minima. Not much point debating what is legit at the MAP when it's not even legal to fly past the FAF. The bottom line is you either have the circling minimums or you don't. But the OP posited that it is illegal to circle, not because of the vis or other restriction at OLBA, but simply because: "Flying overhead to position for the downwind you lose the runway once you turn your tail so you are illegal." I think if that were the case TERPs/PANSOPS would spell it out.

Last edited by oggers; 28th Mar 2019 at 19:39.
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Old 28th Mar 2019, 11:27
  #23 (permalink)  
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First of all thanks for your participation in this discussion.

Originally Posted by aterpster View Post
What about this approach which has zero offset and no straight-in minimums?
I dont fly TERPS but in PANS OPS when a procedure doesnt satisfy for a straight in minimums, they publish circling minimums usually due to offset, steep angles, or protruding obstacles nearby. This doesnt mean that you cant fly a straight in approach, but: Always respecting circling minimums.

Originally Posted by oggers View Post
There is no general prohibition against circling back.



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.
Very nice input. Althought TERPS thats something that i was searching for. Also there are some other maneuvers to make you stay with the runway is sight at all times but it would require to offset in the beginning, then parallel the landing runway and then make a turn when passing the opposite threshold to join downwind.

Originally Posted by sabenaboy View Post
According to ICAO and EU ops, It is not a requirement to have the runway environment in sight at all times.

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.
Sabena boy, well said about the visual approach. Although that was a new chapter popping in the thread, it wasnt my intention to merge also a visual approach for the sake of conversation because when ATC grants a visual approach you can fly as you want.

Originally Posted by sabenaboy View Post
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'.
I think this is the cone of confusion for the law. If losing visual reference due to "airplane structures" is permissible, and for how long. Losing the runway for a second due to wings roll movement could be acceptable but could be different than losing the runway below when overflying the runway for many seconds untill turning downwind.

Originally Posted by Small cog View Post
Lantirn
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.
Of course you can achieve and you can see it with mathematics. The straight in minimums calculating for the VDP require more than 4000m in many NPA's. (disregard the approach lights for simplicity). Although you are legal to start the approach, you can expect that unless the lighting system is very long and powerfull, you will see nothing there. Approaching from above at circling minimums (1000ft minimums = 328m < 4000m visibility), although higher, at some point you will see the runway but you will be too high to land, so you will have to plan for a circling approach. And this is the basis of this thread.

Originally Posted by Small cog View Post
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.
The conversation was for the sake of legality. I didnt say that i would change plan over the minimums and execute another type of approach.
I said that after a missed approach on the straight in, you comeback for a circling approach and briefed.
This was to discuss the legality of this type of circling and not the quality of the decision making, its obvious that its a very very risky approach.

Originally Posted by sonicbum View Post
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.
​​​​​​
Sonicbum,
As i wrote in my opening post, you will find out that I agree with this. I dont think its legal since the beggining. But thats what we are discussing here, to let others justify and get something. What i believe is that you are not allowed and if i was 100% sure i wouldnt be discussing here.
I say again, the amount of responses i get by professionals outside vary alot...and thats scary guys.

Originally Posted by sabenaboy View Post
Small cog
The OP poster did not ask if it was wise to fly the scenario he was describing, he was asking about legality:

And I had already said:
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.
Sabenaboy, well said again regarding my legal-bound focus.

Originally Posted by Small cog View Post
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.
Small cog I agree with you when flying OLBA. But I already mentioned OLBA was a bad example by me. There is no point in finding out another approach plate, they are dozen out there.
1)Assume you are cleared for a circling approach same runway.
2)Assume MAP is over the runway.
3)Disregard all circling sector prohibitions limitations


Originally Posted by custardpsc View Post
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)
Really? My minimums for this plate on circling are 2.4V. Lido provider. Strange.

Originally Posted by custardpsc View Post
But, circling minima are higher in general than approach minima for obvious reasons, so its likely that in the general case of a marginal approach viz circling wouldn't be an option.
Well, look in this post above for further explanation why you would benefit with visual cues.
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Old 28th Mar 2019, 12:55
  #24 (permalink)  
 
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Lantirn,

Is then your question “is it permissible to make a visual approach to a r/w if you see it when the vis is below the instrument approach minima?”

If so, NO. A visual approach to a r/w for which there is an approach in force (ie working) is not permitted when the required approach minima are below that required for the instrument procedure. The 800 metres does not apply in such cases either.

Back in the 1970s/80s it used to happen often when transometers were under shallow layer of fog. Pilots would call “visual” and continue to land. Rules tightened to prevent such occurrences decades ago.
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Old 28th Mar 2019, 13:50
  #25 (permalink)  
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Originally Posted by Small cog View Post
Lantirn,

Is then your question “is it permissible to make a visual approach to a r/w if you see it when the vis is below the instrument approach minima?”

If so, NO. A visual approach to a r/w for which there is an approach in force (ie working) is not permitted when the required approach minima are below that required for the instrument procedure. The 800 metres does not apply in such cases either.

Back in the 1970s/80s it used to happen often when transometers were under shallow layer of fog. Pilots would call “visual” and continue to land. Rules tightened to prevent such occurrences decades ago.
Hi small cog,

No, I am not referring to any visual approach, neither to any bust of approach ban minima. Disregard OLBA.

Achieving the visual reference above the runway at an NPA (behind any MAP point, at circling minima altitude, when coming planned for circling approach) and position/maneuver to land to any runway, is not a visual approach. It’s just the visual maneuver part of the circling approach. It’s an IFR procedure with a visual maneuvering that remains a strictly IFR procedure. Visual approach is a different story with other visual references required which I don’t question at.

The question is:

Are you allowed to execute a circling approach for the straight in runway? More specifically, are you allowed to lose contact with the runway environment (due to aircraft movement-and not due to external weather conditions) when maneuvering for the downwind?

Some say yes, some say no. That’s the discussion.
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Old 28th Mar 2019, 14:29
  #26 (permalink)  
 
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Originally Posted by Lantirn View Post



Some say yes, some say no. That’s the discussion.
EU Ops Definitions:
Circling: the visual phase of an instrument approach to bring an aircraft into position for landing on a runway which is not suitably located for a straight-in approach.

The flight maneuvers should be conducted within the circling area, and in such a way that a visual contact with the runway, or the runway environment, is maintained at all times.

To me it is pretty clear Your example is not allowed.
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Old 28th Mar 2019, 15:01
  #27 (permalink)  
 
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Originally Posted by sonicbum View Post
EU Ops Definitions:
Circling: the visual phase of an instrument approach to bring an aircraft into position for landing on a runway which is not suitably located for a straight-in approach.

The flight maneuvers should be conducted within the circling area, and in such a way that a visual contact with the runway, or the runway environment, is maintained at all times.

To me it is pretty clear Your example is not allowed.
So tell me why this guy is wrong:

Circling to land straight-in Figure 4 [Fig 4 shows circling 180° to the D/W before landing on the stright-in runway as per the OP] is the method I recommend for handling a situation like the MFR IAP, where you aren’t comfortable landing straight-in. The first reaction of both pilots and controllers is to “do a 360 on final” rather than what I’ve illustrated. A 360 degree turn on final is fine on a clear VFR day. That’s not the type of day with which this article is concerned,however. I’m assuming night or day with precip, bumps, gusty winds,etc. When you really need to circle at MFR, Figure 4 is the way to do it. Fly down the runway at MDA until it’s about to disappear under the nose,then enter the close-in circle-to-land maneuver.

Wally Roberts is a retired airline captain, former chairman of the ALPA TERPs Committee, and an active CFII in San Clemente, CA
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Old 28th Mar 2019, 15:12
  #28 (permalink)  

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Originally Posted by Lantirn View Post
are you allowed to lose contact with the runway environment (due to aircraft movement-and not due to external weather conditions) when maneuvering for the downwind?
My understanding (and training) within JAA -> EUOPS -> EASA IR is a clear no for the circle to land. That one needs to be "eyes on the airfield" at all times.

For a visual approach (approach procedure segment of IFR flight, to correct Iron Eagle above), OTOH it is perfectly legal. Navigate by visual means, understand the implications on (reduction of) ATC service provided and enjoy at own peril. VOR let-downs in CFU are a nice example.

The references for both have been already provided in the posts above, I guess.
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Old 28th Mar 2019, 15:22
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Originally Posted by oggers View Post
So tell me why this guy is wrong:
He could be, against the EASA rules. Which BTW prescribe an immediate G/A upon reaching what the US calls DDA.

Though I would say, by your description of FIG 4, that the manoeuvre is NOT in disagreement. If you overfly the runway and bank for downwind, just by looking down you could be able to see the inside of the airport fence still.

---
Sorry to muddy the waters a bit more even: the does the "runway environment" in circle-to-land EASA frame, have a definition? I seem to remember it actually does, and "inside airport fence" I just wrote above does not suffice.

Last edited by FlightDetent; 28th Mar 2019 at 17:51.
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Old 28th Mar 2019, 15:48
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Originally Posted by Lantirn
Really? My minimums for this plate on circling are 2.4V. Lido provider. Strange.
Yep, indeed, Lido shows 2400 m as visibility requirement!

Originally Posted by Lantirn
The question is:
Are you allowed to execute a circling approach for the straight in runway? More specifically, are you allowed to lose contact with the runway environment (due to aircraft movement-and not due to external weather conditions) when maneuvering for the downwind?
Some say yes, some say no. That’s the discussion.
Originally Posted by sonicbum
The flight maneuvers should be conducted within the circling area, and in such a way that a visual contact with the runway, or the runway environment, is maintained at all times.
To me it is pretty clear Your example is not allowed.
And I would think that it's ok if you don't see the rwy temporarily by airframe obstruction.
I would think that it is ok to temporarily have the rwy sight obstructed by the airframe while joining downwind as long as you stay within the circling visual manoeuvring area. The rule was ment to indicate that it's not ok to loose sight of the rwy due to reducing visibility or entering clouds. Would you want a high wing aircraft to go around if the wing hides the runway temporarily when turning to base leg? Or a low winged aircraft that loses sight of the rwy when he banks away from the center line to join downwind for the opposite rwy? In your interpration that would oblige the pilot to abandon the circling!

Take a look at the LGIR VOR 27.

I think it would be perfectly LEGAL to maintain 1140 to IRA 1.5DME (Too high for straight in) continue overhead and then turn right to join downwind for rwy 27. I think that would be legal and not more dangerous then circle to land for rwy 09.
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Old 28th Mar 2019, 15:52
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It’s an interesting question, which I had to re-read in order to see exactly what it was getting at.

In my airline, generically I’d have two options:

a) fly the NPA using a CDA to MDA then continue for a straight-in or GA,
b) fly the NPA to circling minima then “circle”, as long as I had achieved visual reference before the MAP.

You could make the argument that due to the weather, the runway was not suitable for a straight-in and as long as you had sight of the runway environment, which you should do as you’re over the airfield, then that satisfies the regulations, especially if you offset dead-side a little.

The actual conditions vs. minima makes a big difference as well. If you have visual conditions you can always “revert” to VFR and fly circuits but you’re constrained to the circling area if not.

Overall, I think there is enough to make a decent defence over the legality of such a manoeuvre but if it’s that marginal that you can’t see the airfield off the instrument approach, personally I’d go somewhere else...
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Old 28th Mar 2019, 15:57
  #32 (permalink)  
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Ok let’s assume it’s legal.

Its a very good reason to forget everything we know about legislation and eventually disregard all the minimums. Why?

Because everytime, we could just fly overhead and if we could “see the runway”, we could maneuver the airplane and land. It just doesn’t make sense to me.

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Old 28th Mar 2019, 16:15
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Because everytime, we could just fly overhead and if we could “see the runway”, we could maneuver the airplane and land. It just doesn’t make sense to me.
Only if the wx vs. minima permitted it and it was allowed by charts/ATC/operator, etc. Also, you’d have to maintain whatever reference was required, which if the conditions were poor might not happen. It would also reduce the flow rate while you were enjoying yourself in the circuit...

P.S. That’s effectively what you do with a “breakcloud” procedure.

P.P.S. I’m not saying it’s a good idea in all circumstances but that wasn’t the original question?
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Old 28th Mar 2019, 16:42
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Lantirn, let's ask what is a circle-to-land. A manoeuvre executed at the MDA inside the protected area to bring an aeroplane to land. As long as we are talking what's legal, there is no mention to which runway or what type of trajectory is allowed. Thus as long as you maintain the runway or its (immediate) environment in sight, you're authorised (all other boxes assuming ticked, no matter how unlikely).

Admittedly some of the examples above are solved by a simple straight in landing anyway, so debating too deep is pointless.
Line-of sight obstructed by airframe parts does not sound as a show stopper. Leaving the airport behind in turn - I think that would be one.

Yet circle to lands are intended to get you to a non-straight-in runway in a low cloud overcast conditions. In good weather when the 3 deg CDFA is for some reason obstructed, ask for and declare a visual (still IFR proceudure) and get away from the runway in-sight restriction. Sorted.

Last edited by FlightDetent; 28th Mar 2019 at 17:39.
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Old 28th Mar 2019, 16:50
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Originally Posted by Lantirn View Post
Because everytime , we could just fly overhead and if we could “see the runway”, we could maneuver the airplane and land.
While observing the minima to get there - yes.






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Old 28th Mar 2019, 17:12
  #36 (permalink)  

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Case study "inspired by real events". Cloud layer bottom approx. 1200 AFE, inside 6 miles top of cover around 1800'.






(the MDA shaded area is symbolic, should be a bit higher to intersect the profile by 6 NM.)
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Old 28th Mar 2019, 17:19
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Or something like this, which I had to do not that long ago due to the VOR being out and a NAV UNABLE RNP of all things...



Effectively a breakcloud procedure...
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Old 28th Mar 2019, 17:28
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Originally Posted by FlightDetent View Post
Could be, against EASA rules. Which BTW prescribe an immediate G/A upon reaching what the US calls DDA.
Yes and another point that renders the original scenario moot for operators under EU-OPS. But still not a general prohibition under ICAO.

Sorry to muddy the waters a bit more even: the does the "runway environment" in circle-to-land EASA frame, have a definition? I seem to remember it actually does, and "inside airport fence" I just wrote above does not suffice.
According to PANSOPS
The runway environment includes features such as the runway threshold or approach lighting aids or other markings identifiable with the runway.
Also, back in the day when my source documents were JSP318 and The Flight Planning Doc there was another phrase, words to the effect 'or for a circling approach any other feature that positively fixes the aircraft's position relative to the runway'. I think if ICAO did not want a pilot to circle back to the straight-in runway they would simply say as much.




Circling approaches such as this tell me that the FAA at least think you can maintain the runway environment in sight whilst putting your tail to the runway.
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Old 28th Mar 2019, 17:45
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Thanks for digging the runway environment. You may have a point with that plate, but tail-to-runway still allows sight of the threshold in case of a left/right break, does it not?
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Old 28th Mar 2019, 17:48
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Originally Posted by oggers View Post
So tell me why this guy is wrong:
Because A) if the landing runway has an useable IAP You either fly it or fly a visual approach, not a circle to land and B) 99.9% of EASA Operators comply with CDFA approaches regulations, therefore You can't level off and wait for the Mapt whilst being levelled.
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