Class D base "FL060 or 1500ft AGL"
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Class D base "FL060 or 1500ft AGL"
There are lots of places in Europe where CAS has a base marked like that, and below it is Class G.
So one has a 1500ft gap of Class G.
My Q is how closely does the Class D base follow the contours below it? If the terrain changes from say 3000ft AMSL to 10000ft AMSL then the base of the Class D will fluctuate between (roughly) 6000ft and 11500ft, and I don't really see a 737 following that
Or any other aircraft for that matter.
When in the past I flew VFR through such regions (Italy comes to mind) I would just fly 1500ft above the highest obstacle within say 20-30nm, and didn't have any trouble. But that could have still been infringing Class D.
Is there some international rule for where the base of such airspace really lies? Do they take the highest peak within say 10nm?
One could get an idea by looking up airways in the area and look at their MEAs, but that isn't something you would expect of a VFR pilot... it also doesn't tell you anything about the base of the CAS.
So one has a 1500ft gap of Class G.
My Q is how closely does the Class D base follow the contours below it? If the terrain changes from say 3000ft AMSL to 10000ft AMSL then the base of the Class D will fluctuate between (roughly) 6000ft and 11500ft, and I don't really see a 737 following that
Or any other aircraft for that matter.When in the past I flew VFR through such regions (Italy comes to mind) I would just fly 1500ft above the highest obstacle within say 20-30nm, and didn't have any trouble. But that could have still been infringing Class D.
Is there some international rule for where the base of such airspace really lies? Do they take the highest peak within say 10nm?
One could get an idea by looking up airways in the area and look at their MEAs, but that isn't something you would expect of a VFR pilot... it also doesn't tell you anything about the base of the CAS.
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I've flown these a few times and asked myself the same question.
Torino seem quite happy if you tell them you are climbing to 10,000' as soon as you enter the valley (Val Susa or Val d'Aosta). Like you, I've taken it to mean separation from ground as defined for IFR (i.e. within 10nm).
You're pretty unlikely to encounter IFR traffic below FL100 near the Alps, and chances are you'll lose VHF reception for part of the crossing anyway.
It'd be interesting to know the strict definition.
Torino seem quite happy if you tell them you are climbing to 10,000' as soon as you enter the valley (Val Susa or Val d'Aosta). Like you, I've taken it to mean separation from ground as defined for IFR (i.e. within 10nm).
You're pretty unlikely to encounter IFR traffic below FL100 near the Alps, and chances are you'll lose VHF reception for part of the crossing anyway.
It'd be interesting to know the strict definition.
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Just found this thread - although quite old, seems related to something I'm trying to understand.
I am going to fly some VFR in the Torino area in Italy, and like IO540 says there's quite a lot of controlled airspace marked a certain altitude or a height AGL.
Not only class D, there quite a lot of Class A between Turin or Milan which is marked 2000ft (1000 AGL).
Majority of those areas have ground well above 1000ft so what's the point in having the 2000ft constraint ?
Also, with just 1000 ft AGL and the profile changing quite dramatically within short space, I suspect it would be quite easy to infringe class A, which is not something I am intending to do, especially with so many Military areas nearby
Last thing I want is having to pay the fuel bill of a Tornado ADV....
Anybody with experience in that area and advice ?
Thanks
H.H.
I am going to fly some VFR in the Torino area in Italy, and like IO540 says there's quite a lot of controlled airspace marked a certain altitude or a height AGL.
Not only class D, there quite a lot of Class A between Turin or Milan which is marked 2000ft (1000 AGL).
Majority of those areas have ground well above 1000ft so what's the point in having the 2000ft constraint ?
Also, with just 1000 ft AGL and the profile changing quite dramatically within short space, I suspect it would be quite easy to infringe class A, which is not something I am intending to do, especially with so many Military areas nearby
Last thing I want is having to pay the fuel bill of a Tornado ADV....
Anybody with experience in that area and advice ?
Thanks
H.H.
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I never managed to find out the answer to this one.
Most likely, it is that nobody cares. Italy is covered in low level airspace which is ridiculously low - far too low to contain any traffic anywhere near its base. Just look at that huge Class A area extending to the west of Italy, down to 1000ft. There is no way for any commercial ops to be down there.
Most likely, it is that nobody cares. Italy is covered in low level airspace which is ridiculously low - far too low to contain any traffic anywhere near its base. Just look at that huge Class A area extending to the west of Italy, down to 1000ft. There is no way for any commercial ops to be down there.
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Interesting !
So it's Class A which isn't really Class A !
Mind you, a bit like traffic lights in Italy, when red, "cross with care". When green, "Cross. Careful, someone could be crossing with a red light from the other side"
Thanks for the reply
So it's Class A which isn't really Class A !
Mind you, a bit like traffic lights in Italy, when red, "cross with care". When green, "Cross. Careful, someone could be crossing with a red light from the other side"
Thanks for the reply
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No, you can't fly in Italian Class A. What I was saying is that there is no apparent reason for having it. You can be assured that if you fly into it they will go after you.
The areas which this thread was referring to were (IIRC) mostly Class D. That is still controlled airspace, but it's obviously difficult to decide where the base of it is, over undulating terrain. I think that nobody gets too concerned provided you don't do anything too unreasonable.
There may be an ICAO rule for specifying the terrain base in these cases but I have never found anybody who knows about it.
The areas which this thread was referring to were (IIRC) mostly Class D. That is still controlled airspace, but it's obviously difficult to decide where the base of it is, over undulating terrain. I think that nobody gets too concerned provided you don't do anything too unreasonable.
There may be an ICAO rule for specifying the terrain base in these cases but I have never found anybody who knows about it.
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I don't think there is a rule. I'm pretty sure that it's exactly as it says...2000AGL. Any graphic I've ever seen suggests it follows the terrain exactly.
However as IO540 says nobody cares. So the simpliest way to deal with it, is to ask the controlling authority for a clearance through it at an appropriate level. If it's so low that the commericals aren't interesting in using that level, then you should have no problem getting a clearance. That way you are covered, and everyone is happy.
Obviously this doesn't work so good with Class A.
dp
However as IO540 says nobody cares. So the simpliest way to deal with it, is to ask the controlling authority for a clearance through it at an appropriate level. If it's so low that the commericals aren't interesting in using that level, then you should have no problem getting a clearance. That way you are covered, and everyone is happy.
Obviously this doesn't work so good with Class A.
dp
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In the US this airspace structure is designed to allow IFR aircraft to get off the ground from a non-tower airport (so they are IFR in G without ATC contact and then make contact when they are in the air) or in relatively flat terrain to allow for an area for VMC flight in poor viz (i.e. clear of cloud and in sight of surface, aka scud running) or for a corridor under controlled airspace (also normally in relatively flat terrain).
For really undulating terrain the gap under CAS isn't really usable.
In the case of a mountain hole (say a plain 20 miles in diameter at 5000 ft with peaks to 10000) you could get potentially have an IFR approach into an airport there, as such 1500 AGL would be 6500 in the plain and then follow the mountains up.
For really undulating terrain the gap under CAS isn't really usable.
In the case of a mountain hole (say a plain 20 miles in diameter at 5000 ft with peaks to 10000) you could get potentially have an IFR approach into an airport there, as such 1500 AGL would be 6500 in the plain and then follow the mountains up.
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If it's so low that the commericals aren't interesting in using that level, then you should have no problem getting a clearance.
Unfortunately, this doesn't work in Italy
The way to fly VFR there, as in many other places, is to fly at a high level, say FL080, on a VOR-VOR-VOR route. Firmly request "G-xxxx request [give the relevant section of your route] at FL080".
Those who ask, firmly but politely, get the routes they want!
And stay on the ball, because the handovers may not work, so if it looks like they are going to forget you (and leave you at FL080 in Class D with nobody to talk to) make the call asking for the handover, or just ask for the next bit of the route which will be just as plain.
Always read back everything carefully, with "cleared to transit XX-XX-XX", for the tape. ATC abroad is laid back and they often don't clear you explicitly.
ATC everywhere prefer pilots who fly like this because it tells them you know what you are doing. Navaid and airways intersection names are the way to do it. The moment they get somebody rolling off obscure VRP names they will be more concerned.
One still needs a backup plan, outside CAS. I always had to invoke this when I used to go down there VFR, because they tend to suddenly forget about you. A decent GPS is a must, obviously.
If there is low cloud then you will probably have to fly either the published VFR routes, or just sit offshore over the sea, away from the Class D airport circles.
Unfortunately, this doesn't work in Italy
The way to fly VFR there, as in many other places, is to fly at a high level, say FL080, on a VOR-VOR-VOR route. Firmly request "G-xxxx request [give the relevant section of your route] at FL080".
Those who ask, firmly but politely, get the routes they want!
And stay on the ball, because the handovers may not work, so if it looks like they are going to forget you (and leave you at FL080 in Class D with nobody to talk to) make the call asking for the handover, or just ask for the next bit of the route which will be just as plain.
Always read back everything carefully, with "cleared to transit XX-XX-XX", for the tape. ATC abroad is laid back and they often don't clear you explicitly.
ATC everywhere prefer pilots who fly like this because it tells them you know what you are doing. Navaid and airways intersection names are the way to do it. The moment they get somebody rolling off obscure VRP names they will be more concerned.
One still needs a backup plan, outside CAS. I always had to invoke this when I used to go down there VFR, because they tend to suddenly forget about you. A decent GPS is a must, obviously.
If there is low cloud then you will probably have to fly either the published VFR routes, or just sit offshore over the sea, away from the Class D airport circles.
