They are difficult to fly in poor conditions and maintain tolerances.
They require intense crew coordination, often with inexperienced and low-time new co-pilots.
They require a certain level of skill which is acquired over a long period of time, and many new Captains have not acquired this level of skill in normal flying
The SOPs for many companies and types are different, leading to confusion in the cockpit, even after lengthy briefings.
They can't be trained for easily to fly in shit conditions when you've only been trained in blue-sky-goodbye conditions.
And FINALLY...they are simply not required with the advent of GPS approaches on both ends of a runway/s
swordfish wrote: ↑Thu Feb 20, 2020 9:40 am
Where did they go?...are going?
GONE, I hope.
They are difficult to fly in poor conditions and maintain tolerances.
They require intense crew coordination, often with inexperienced and low-time new co-pilots.
They require a certain level of skill which is acquired over a long period of time, and many new Captains have not acquired this level of skill in normal flying
The SOPs for many companies and types are different, leading to confusion in the cockpit, even after lengthy briefings.
They can't be trained for easily to fly in shit conditions when you've only been trained in blue-sky-goodbye conditions.
And FINALLY...they are simply not required with the advent of GPS approaches on both ends of a runway/s
Business aviation continues to use circling approaches to specific airports.
Training in the simulator and on the ride requires a circling down to mins, low visibility and at night. Despite knowing what's coming it can still be a challenge, especially for pilots transitioning from props to jets.
I think airline wise, circling is all but transitioned out.
It depends what type of certification the circling approach is based on. I fly a Cat. D circling aircraft so will discuss with reference to it.
A TERPS circling approach at Cat. D has a protected area of 2.3NM. If you are to be stable on approach at 300’ and 1NM as per a lot of SOP’s (which is far to low and close in, imho) and circling at 150ktas your turn radius will be 0.84NM in zero wind conditions (when was the last time you circled in zero wind), which means that if you flew it perfectly on the edge of the protected airspace you’d have 0.46NM to roll the wings level align on the runway be on vref speed before the 300’ mark. Very difficult indeed. Add in any overshooting wind and it can’t be done. Now if you add in a 2sm (1.7NM) minimum visibility as is quite common it becomes impossible as you would have to keep the airport in sight at 2sm (1.7NM) 1.7-0.84=0.86NM you miss the stable approach mark. As a result of this I will not fly a TERPS circling approach in anything other than VFR conditions which really means just a visual approach.
Expanded TERPS helps out quite a bit with the protected area being 3.6 to 4.4NM depending on your MDA MSL but does nothing about the minimum visibility issue or winds. These circling approaches I will do but only if the visibility matches the protected area.
Lastly Pans-Ops, I have 4.2NM protected area based on winds at 25kts through out the turn. 20 degrees bank angle or 3 degrees/sec whichever is less. These are quite safe, stable and doable.
swordfish wrote: ↑Thu Feb 20, 2020 9:40 am
Where did they go?...are going?
GONE, I hope.
They are difficult to fly in poor conditions and maintain tolerances.
They require intense crew coordination, often with inexperienced and low-time new co-pilots.
They require a certain level of skill which is acquired over a long period of time, and many new Captains have not acquired this level of skill in normal flying
The SOPs for many companies and types are different, leading to confusion in the cockpit, even after lengthy briefings.
They can't be trained for easily to fly in shit conditions when you've only been trained in blue-sky-goodbye conditions.
And FINALLY...they are simply not required with the advent of GPS approaches on both ends of a runway/s
---------- ADS -----------
"If nothing else works, a total pig-headed unwillingness to look facts in the face will see us through."
In Canada, you are expected to circle AT the minimum altitude with precision (50' tolerance), you cannot go any lower than the minimum altitude for circling, and in a wind, bad vis, and constantly ..-running the bases, judging your turns, staying on the commanded speeds, meanwhile trying to solicit intelligent input from your scared-shitless newbie copilot, it requires superior skill.
Additionally if you encounter cloud and lose visual - even for a few seconds, it's an automatic missed approach FOR THE ORIGINAL APPROACH PROCEDURE. i.e. if you're downwind or about to turn base, and you are forced to miss, the procedural rule is that you turn towards the centre of the airport, and conduct a missed approach. Totally ridiculous when you're already going in the direction of the missed approach - you have to make one tight turn to the center of the airport, then another to get onto the MA track. It's even more difficult when you're abeam the centre of the airport, and close in.
The procedures are absurd, and so is the concept. Additionally you already have lower minima coming straight in from the other end (assuming there IS in fact an approach on the other end).
No wonder the airlines are shunning them. They are stressful, and fraught with errors.
I have been flying a biz jet for 30 years. I have done exactly 30 circling approaches in that time either at FSI or Simuflite. If those 2 numbers don’t equal each other you need to find a better job
I've been flying in the North for 45 years, and have done probably 100 of them in real time - not to mention the ones in sims (for types I flew that had sim training). I'll be happy to see them completely gone from the IFR procedures. 30/30 is a probably good estimate in sims...
First circling approach I ever did was to Runway 25 in Abbotsford during my initial IFR course. It was raining and the ceiling was right at circling minimums. The view out the windshield was not what I was expecting. Instead of a nice horizon and a brightly lit obvious runway there was a whole bunch of really blurry lights.
About half way along the downwind all the lights went out, so I blurted out “where did all the lights go” ? My instructor replied “ You are in cloud dummy ! GO AROUND !!! ”
It was a very valuable lesson in how quickly circling approaches in bad weather can go bad, especially at night.
IIRC, some time back, Transport Canada asked the major airlines to show that their Level D simulators were capable of presenting adequate visuals to represent a circling environment. At the time, none of the simulators had such a capability because the side visuals didn't go past 90 degrees. This certainly helped to push them away from having circling as an option in their COMs.
swordfish wrote: ↑Thu Feb 20, 2020 8:05 pm
In Canada, you are expected to circle AT the minimum altitude with precision (50' tolerance), you cannot go any lower than the minimum altitude for circling, and in a wind, bad vis, and constantly ..-running the bases, judging your turns, staying on the commanded speeds, meanwhile trying to solicit intelligent input from your scared-shitless newbie copilot, it requires superior skill.
Additionally if you encounter cloud and lose visual - even for a few seconds, it's an automatic missed approach FOR THE ORIGINAL APPROACH PROCEDURE. i.e. if you're downwind or about to turn base, and you are forced to miss, the procedural rule is that you turn towards the centre of the airport, and conduct a missed approach. Totally ridiculous when you're already going in the direction of the missed approach - you have to make one tight turn to the center of the airport, then another to get onto the MA track. It's even more difficult when you're abeam the centre of the airport, and close in.
The procedures are absurd, and so is the concept. Additionally you already have lower minima coming straight in from the other end (assuming there IS in fact an approach on the other end).
No wonder the airlines are shunning them. They are stressful, and fraught with errors.
As soon as you’re visual you’re visual.
Staying at MDA and trying to stay in the protected area for the entire circling procedure is what often makes circling approaches more dangerous.
Once you’re visual and can stay, say visual and call leaving MDA and maneuver outside the protected area as appropriate.
For missed approach, the same minimums and protected areas apply for each category. You’re not going to hit anything while climbing above MDA and maneuvering yourself within the protected area to do the original MAP.
iflyforpie wrote: ↑Fri Feb 21, 2020 10:58 am
Once you’re visual and can stay, say visual and call leaving MDA and maneuver outside the protected area as appropriate.
Are you certain of that?
TC AIM 9.24 Circling Procedures
" An air traffic controller may specify manoeuvring in a certain direction or area due to traffic considerations; however, the selection of the procedure REQUIRED TO REMAIN WITHIN THE PROTECTED AREA and to accomplish a safe landing rests with the pilot. There can be no single procedure for conducting a circling approach due to variables such as runway layout, final approach track, wind velocity and weather conditions. The basic requirements are to keep the runway in sight after initial visual contact, AND REMAIN AT THE CIRCLING MDA UNTIL A NORMAL LANDING IS ASSURED."
I suppose if you were flying into an airport under ATC control you could after sighting the airport ask for a visual approach but that would require the weather be 3sm vis. and ceiling 500ft above minimum IFR altitude. Or again if a control zone once clear of cloud with 1sm vis. ask ATC for a Special VFR cancel IFR and proceed that way but both of those would be asking for trouble. Otherwise the weather would have to be VFR then you could do a cloud break cancel the IFR and proceed VFR to the airport.
---------- ADS -----------
"If nothing else works, a total pig-headed unwillingness to look facts in the face will see us through."
iflyforpie wrote: ↑Fri Feb 21, 2020 10:58 am
Once you’re visual and can stay, say visual and call leaving MDA and maneuver outside the protected area as appropriate.
Are you certain of that?
TC AIM 9.24 Circling Procedures
" An air traffic controller may specify manoeuvring in a certain direction or area due to traffic considerations; however, the selection of the procedure REQUIRED TO REMAIN WITHIN THE PROTECTED AREA and to accomplish a safe landing rests with the pilot. There can be no single procedure for conducting a circling approach due to variables such as runway layout, final approach track, wind velocity and weather condition. The basic requirements are to keep the runway in sight after initial visual contact, AND REMAIN AT THE CIRCLING MDAUNTIL A NORMAL LANDING IS ASSURED."
I’m absolutely certain of that.
The context isn’t gliding distance. Or engine out operations. It’s exactly as I said... “once you are visual and can stay visual”.
I am wondering what the reasoning is behind not being allowed to climb. Not going lower makes sense obstacle wise, but why not go a bit higher if the weather allows it?
Is there some weird design constraint I am not aware of?
---------- ADS -----------
As an AvCanada discussion grows longer:
-the probability of 'entitlement' being mentioned, approaches 1
-one will be accused of using bad airmanship
You don't have to descend to the MDA to circle, if the weather allows - you can circle higher, if you want. So of course you can climb. You just can't go any lower, until a normal landing is assured.
---------- ADS -----------
DId you hear the one about the jurisprudence fetishist? He got off on a technicality.
iflyforpie wrote: ↑Sat Feb 22, 2020 10:47 am
Be a dear and look up RNAV A into Kelowna and tell me how you’d ever get down to the runway within the protected area and at circling MDA.
iflyforpie wrote: ↑Fri Feb 21, 2020 10:58 am
Once you’re visual and can stay, say visual and call leaving MDA and maneuver outside the protected area as appropriate.
Are you certain of that?
TC AIM 9.24 Circling Procedures
" An air traffic controller may specify manoeuvring in a certain direction or area due to traffic considerations; however, the selection of the procedure REQUIRED TO REMAIN WITHIN THE PROTECTED AREA and to accomplish a safe landing rests with the pilot. There can be no single procedure for conducting a circling approach due to variables such as runway layout, final approach track, wind velocity and weather condition. The basic requirements are to keep the runway in sight after initial visual contact, AND REMAIN AT THE CIRCLING MDAUNTIL A NORMAL LANDING IS ASSURED."
I’m absolutely certain of that.
The context isn’t gliding distance. Or engine out operations. It’s exactly as I said... “once you are visual and can stay visual”.
I agree it has nothing to do with gliding distance or engine out operations, I never said it did. It does however have everything to do with as I stated before, required to remain in the protected area and at MDA until a normal landing is assured. So how do you get down from MDA on the RNAV A in Kelowna? Well if you stay at MDA until inside the protected area (Lets use Cat D 2.3NM) at my planes circling speed of 150ktas well that means a decent rate of 1800ft/min to the threshold, that is not a normal landing nor safe. The only way then is to not try a straight in landing but rather maintain MDA overfly the runway and do a left circling circuit leaving MDA as you turn from downwind to base (a normal place to decend for landing) at 1300ft/min until 1nm and 300ft from the threshold then you are on a nice 3 degree 600ft/min decent from there to landing. I will grant you that this only works mathematically in ideal zero wind conditions. And is why I won't do a TERPs designed circling approach ( they are quite often impossible.) Even if you called visual and left MDA at 3SM as you are proposing your decent rate from there to the threshold would be in the range of 1500ft/minute. Which isn't a normal landing either.
Legend:
Green Ring 3SM visibility
Magenta line circling path
Yellow 2.3NM protected area
Blue line RNAV A approach path from ELSEN to ADSOT
IMG_0197.jpg (1.49 MiB) Viewed 1462 times
---------- ADS -----------
"If nothing else works, a total pig-headed unwillingness to look facts in the face will see us through."
iflyforpie wrote: ↑Fri Feb 21, 2020 10:58 am
I’m absolutely certain of that.
The context isn’t gliding distance. Or engine out operations. It’s exactly as I said... “once you are visual and can stay visual”.
You have to fly the approach you have been cleared for. You can't just declare yourself to be on a visual approach; you can request it and ATC will generally grant it if the requirements are met, or you can cancel IFR if weather permits. As has been stated, the weather minimums are quite high for a visual approach. If they are met you probably don't need to circle in the first place.