I flew yesterday from my homebase Nuthampstead to Lydd. My usual route to the southeast is as the diagram below. When I am clear of Stanstead class D airspace I climb to 3000ft and contact Southend for zone transit. The controller asked me whether I was VFR or IFR. Just to see what would happen I declared I was IFR. This resulted in “unable to offer zone transit due to controller workload…” I thought, typical, this is Southend bigging themselves up now that they have class D status! I now detoured down the western side of their airspace. I called the controller and asked him, that if I had declared myself VFR, would that have made any difference to the clearance? He said yes and he would have been able to offer zone transit VFR. With IFR they have to provide certain spacing to IFR traffic, and as he had two aircraft in the hold, he couldn’t take one more. This doesn’t make much sense to me. If there was two aircraft in the hold how could it be OK to allow VFR traffic through but not IFR traffic. If Southend was operating without radar (I did not establish that) then I could see that procedural service limits would have to apply, but I suspect that what was happening was the systematic tightening of allowing traffic through their zone despite their assurances when class D status was approved, that this wouldn’t be so.
Has anybody else experienced any tightening up on zone transits?
this doesn’t make much sense to me. If there was two aircraft in the hold how could it be OK to allow VFR traffic through but not IFR traffic.
These are absolute basics of air law and ICAO airpace classes. In class Delta, IFR must be separated from other IFR. But VFR does not. Hence, it makes sense to request a transit under VFR.
At the same time ATC don’t want you to hit one of their 737s, and since they probably don’t know if you are in VMC or IMC, and spotting other traffic is damn hard at the best of times 
… the distinction seems to be a CYA exercise.
Peter wrote:
… the distinction seems to be a CYA exercise.
I agree.
If you were just starting out in the flying game, you accept all this as normal, but for us old dogs it seems that procedures change for reasons that are never explained in any official literateture that I have ever seen?
Propman wrote:
that procedures change for reasons that are never explained in any official literateture that I have ever seen?
Class D has worked that way ever since the alphabetic airspace classification was introduced 25 years ago. It has been in every pilot license TK for that long as well. It has been in the ICAO Rules of the Air. It has been in the AIP of essentially every country. It is in SERA. How can it be more official?
Indeed, what flights are separated is the one difference between classes B, C and D. As boscomantico said, this is about as basic as it gets.
Technically so, but this is crossing controlled airspace so ATC put you where they want you.
So the matter of separation is a technicality. It is something you do in the PPL theory.
Are they really expecting you to self separate from the inbound Easyjet if you declare yourself “VFR” but not if you declare yourself “IFR”?
On top of that, they are supposed to be providing you with a radar service!
Peter wrote:
Are they really expecting you to self separate from the inbound Easyjet if you declare yourself “VFR” but not if you declare yourself “IFR”?
Possibly not, but they don’t need to apply standard separation criteria.
Airborne_Again wrote:
Are they really expecting you to self separate from the inbound Easyjet if you declare yourself “VFR”
Sometimes they are. I once was asked by Edinburgh whether I was seeing the Boeing, when I answered I did, I got cleared to cross their CTR behind the Boeing…
Why would you want an IFR transit in VMC – I know you were “testing” the system,
but had it been an IFR transit in IMC then its unlikley there would have been sufficient other traffic such as to require a refusal.
I have found that the few times I have managed a Stansted (not being picky, but I also use to incldue the a) transit it has been in IMC.
IFR / IMC you appear far more likely to obtain a clearance of any class D in the UK, especially if you make it clear that you really are in the murk, even if it might be VMC below.
From the UK perspective, there are two views on VFR v. IFR, especially in Class G.
No UK ATCO will openly admit this (well, none previously have) because it is against the rules, but you have a better chance of a CAS transit where the chances are not that great to start with if you sound like you know what you are doing. No ATCO wants an out of control / lost pilot wondering around “his” CAS. Or even just outside it.
And improving your chances of a transit includes saying you are flying “IFR” rather than “VFR”.
For example an IFR flight might be routing via some navaids or airway intersections. A VFR flight will typically be routing via place names. Sometimes reading out several of these place names is like reading out War and Peace. G-XXXX routing via Upper Warlingham, Lower Grassingham on Thames, Little Fart Upon Avon, Upper Farthingham…
Every little bit helps.
In the OP’s case it does sound like there was some technical reason to do with separation, but I have never seen this before. IFR normally works better.
There are good reasons for the “VFR tool” but they are to do with e.g. departures, where if you are e.g. leaving Le Touquet, VFR traffic can just bugger off and once you are over the water and on your way back to the UK they are happy. But IFR traffic has to wait for separation, which on busy days could take a while. Similarly with arrivals, though I feel more comfortable as an IFR arrival because it is an extra procedural layer between you and somebody else being cleared to land at the same time, etc.
