CAP1800_Class_E_Airspace_Procedures_Consultation_Report_pdf
Class E is an elegant solution for GA because if you are IMC in it then you are IFR in CAS and you need a clearance. That is how the US deals with the issue of IFR traffic popping out of the cloudbase and conflicting with VFR circuit traffic below. The reason why Class E was resisted in the past is that you have to pay the extra controllers required to provide a service in Class E, and since 99% of GA doesn’t pay route charges… OTOH I haven’t read that long document and maybe it doesn’t do it this way.
It seems the CAA is worried that unidentified aircraft in class E could be “stray” IFR aircraft without a clearance and not VFR. For that reason they propose all class E in the UK will be made TMZ’s and that VFR traffic must squawk 7000 (or possibly a listening squawk). In that way unknown aircraft not squawking 7000 can be assumed to be IFR and separation provided to controlled IFR. Obviously providing separation to every unknown aircraft would cause havoc as VFR can operate freely in class E without contact with ATC.
To me this looks rather weird — but I guess the disjointed UK airspace makes it more likely that uncontrolled IFR accidentally enters controlled airspace without a clearance.
TMZs are “good” in that it is easier to bust a pilot who busts CAS. Currently most are non TXP… They are also good for those who fly with active TAS systems.
But unless you provide a radar service in this Class E, traffic busting Class D or Class A from it will still be a “sudden bust” with all the usual consequences for loss of separation. Especially by the time 3000ft or 5000ft is added to the infringer’s Mode C altitude!!! A TMZ does not change this, because the UK still regards the Mode C altitude as “unverified”. If the Class E airspace gets a radar service then the infringer will be “verified altitude” and only 1000ft needs to be added, which would reduce loss of separation incidents.
But can you imagine the provision of such a service to all the weekend traffic in the south east?
Interesting to contrast this with say the Class E in France.
Germany has class E basically everywhere and it works fine, especially in conjunction with radar equipped FIS. It’s funny how we always hear about the great airspace structure of the US on this site when there is a decent example right here in Europe.
MedEwok wrote:
Germany has class E basically everywhere and it works fine, especially in conjunction with radar equipped FIS. It’s funny how we always hear about the great airspace structure of the US on this site when there is a decent example right here in Europe.
I agree that Germany probably has one of the best airspace structures in Europe. But I’m not so sure about having separate FIS and ATC operators in the same airspace.
Peter wrote:
A TMZ does not change this, because the UK still regards the Mode C altitude as “unverified”.
My understanding from glancing the document is that no separation at all would be provided between IFR and aircraft sqawking 7000, as they would be assumed to be VFR and there is no IFR-VFR separation in class E. IFR traffic would be given traffic information about VFR targets and could be given avoidance vectors on request.
What airborne_again writes is what happens in the US: it works just fine there.
