Changes to the VMC Minima in Class D Airspace
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Changes to the VMC Minima in Class D Airspace
Anyone had any thoughts on the change back to the old clear of cloud with surface in sight minima in class D? Not sure that it changes much from my perspective other than less requests for SVFR. Just not great timing with everything else that is going on in the world...?
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Originally Posted by 2 sheds
Legalises what many are doing anyhoo, I suspect!
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Sadly, I suspect you're right but was it because they didn't know better or deliberate action...?
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Originally Posted by Jim59
How is a light aircraft pilot supposed to measure the vertical distance to cloud above him/her reasonably accurately? It's always been guesswork.
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Originally Posted by 2 sheds
Plus - we are talking about Class D - the current met report on ATIS or volmet.
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but otherwise it's pilot interpretation.
2 s
Last edited by 2 sheds; 5th Jan 2021 at 13:50.
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Haven't heard about it, but I suspect it's the minima in class D airspace in a control zone? A can give a few considerations to reducing it in the control zone at least.
From the perspective that no separation between normal VFR and IFR is provided, hence it's see and avoid, it'll bring up some issues.
When you provide traffic information to a VFR, and he stays the required distance from clouds, it'll give both the IFR and VFR ample time to aquire each other then the IFR comes dumping out of the clouds... if the VFR can linger around right below the clouds, that option is removed.
Hence when you get closer to the clouds, by requesting special VFR, ATC will make sure you're separated from other special VFR and IFR flights.
With todays requirements of transponders, it may not be as necessary, since an IFR flight are able to "see" a VFR flight before dumping onto him. And further you could argue that keeping VFR flights from the path of inbound and outbound IFR flights should be sufficient. Furthermore that ATC has an obligation to "avoid collision" between aircraft, so eventhough no separation is required, we may end up in a sticky situation, with the lawyers, if aircrafts collide after being only given traffic information and nothing else.
From the perspective that no separation between normal VFR and IFR is provided, hence it's see and avoid, it'll bring up some issues.
When you provide traffic information to a VFR, and he stays the required distance from clouds, it'll give both the IFR and VFR ample time to aquire each other then the IFR comes dumping out of the clouds... if the VFR can linger around right below the clouds, that option is removed.
Hence when you get closer to the clouds, by requesting special VFR, ATC will make sure you're separated from other special VFR and IFR flights.
With todays requirements of transponders, it may not be as necessary, since an IFR flight are able to "see" a VFR flight before dumping onto him. And further you could argue that keeping VFR flights from the path of inbound and outbound IFR flights should be sufficient. Furthermore that ATC has an obligation to "avoid collision" between aircraft, so eventhough no separation is required, we may end up in a sticky situation, with the lawyers, if aircrafts collide after being only given traffic information and nothing else.
jmm
A rather confused and confusing comment, I thought. Whether operating with or without surveillance equipment, ATC is not going to deliberately descend an IFR flight to the same level as a VFR flight without a mile or two of safe distance between them, plus of course, timely traffic information. At least, I hope that is how you operate. Of course it will have to be borne in mind that the VFR, if slow, may be flying only just below the cloudbase and the aircraft may only have each other in sight fairly late. But as discussed earlier, that is probably how some of them are flying at the moment! I don't follow how you end up with the closing melodramatic scenario.
2 s
A rather confused and confusing comment, I thought. Whether operating with or without surveillance equipment, ATC is not going to deliberately descend an IFR flight to the same level as a VFR flight without a mile or two of safe distance between them, plus of course, timely traffic information. At least, I hope that is how you operate. Of course it will have to be borne in mind that the VFR, if slow, may be flying only just below the cloudbase and the aircraft may only have each other in sight fairly late. But as discussed earlier, that is probably how some of them are flying at the moment! I don't follow how you end up with the closing melodramatic scenario.
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Originally Posted by 2 sheds
jmm
....
2 s
....
2 s
I was merely commenting on the removal of distance to cloud for VFR flights and how it could affect see and avoid.... nothing else. (In a control zone)
How VFR pilots handle it, is not for me to judge, but I expect them to adhere to regulation.
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I've never flown in any control zone in the UK where ATC doesn't apply minimum vertical separation of 1000ft between IFRs and VFRs below them. Hence the "IFR dumping out of the clouds" scenario is impossible.
NorthSouth
In essence you may be sort-of correct but you/we are talking about Class D airspace where separation as such is not applicable between IFR and VFR flights and, with respect, it is misleading if you use that term. Having said that, many units will apply a maximum level restriction so that the VFRs are a known quantity and need only be taken into account when an IFR is climbing or descending through that level band or to obviate the need for traffic information where avoiding action is impractical, for example a VFR departure and an IFR in a holding pattern overhead the aerodrome. However, there is no authority for the application of 1,000 ft as such in those circumstances (unless there is a WT interaction), but neither is there any guarantee of the VFR pilot's height keeping accuracy! It always surprises me though that there seems to be little reaction from the light aviation elements that such restrictions are not cancelled promptly when no longer required for safety. The intention of establishment of Class D airspece is that VFR flights should be free to operate up to the maximum level, albeit with ATC clearance and relevant traffic information.
2 s
In essence you may be sort-of correct but you/we are talking about Class D airspace where separation as such is not applicable between IFR and VFR flights and, with respect, it is misleading if you use that term. Having said that, many units will apply a maximum level restriction so that the VFRs are a known quantity and need only be taken into account when an IFR is climbing or descending through that level band or to obviate the need for traffic information where avoiding action is impractical, for example a VFR departure and an IFR in a holding pattern overhead the aerodrome. However, there is no authority for the application of 1,000 ft as such in those circumstances (unless there is a WT interaction), but neither is there any guarantee of the VFR pilot's height keeping accuracy! It always surprises me though that there seems to be little reaction from the light aviation elements that such restrictions are not cancelled promptly when no longer required for safety. The intention of establishment of Class D airspece is that VFR flights should be free to operate up to the maximum level, albeit with ATC clearance and relevant traffic information.
2 s
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Originally Posted by 2 sheds
He didn't mention it, but the OP was referring to the UK.
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Originally Posted by 2 sheds
...The intention of establishment of Class D airspece is that VFR flights should be free to operate up to the maximum level, albeit with ATC clearance and relevant traffic information....
Quote:
Originally Posted by 2 sheds View Post
...The intention of establishment of Class D airspece is that VFR flights should be free to operate up to the maximum level, albeit with ATC clearance and relevant traffic information....
That would be the UK interpretation then, cause ICAO says otherwise?
Originally Posted by 2 sheds View Post
...The intention of establishment of Class D airspece is that VFR flights should be free to operate up to the maximum level, albeit with ATC clearance and relevant traffic information....
That would be the UK interpretation then, cause ICAO says otherwise?
What are you suggesting that ICAO "says otherwise"? If you could quote references, it would be useful.
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Originally Posted by 2 sheds
No.
What are you suggesting that ICAO "says otherwise"? If you could quote references, it would be useful.
2 s
What are you suggesting that ICAO "says otherwise"? If you could quote references, it would be useful.
2 s
So besides the ability of the pilots to actually do as Annex 2 states, which I see as a training issue. I don't see any reason for removing this minima... unless you take more responsibility from the pilots by providing separation between more or less all flights since, as stated earlier, you remove the ability for aircraft to "aquire" each other is sufficient time to avoid each other.
