Generated by Autorouter and validates at FL060 or below.
Usually this is because the UK (or the country in question) is not notifying these areas to IFPS. Autorouting often went through a part of this area in the past (and could never be flown per ATC). But it’s crazy in this case because you cannot fly anything like this route. That area has been totally prohibited for decades.
But now I see the MON-FRI annotation. Is that real? Today is Saturday. I am going to find out today 
But, curiously, on the way back, it does avoid it
Depends on whether they are using the flexible use of airspace models within their router. If so, then the route will be valid as expressed via EC.
Peter wrote:
But it’s crazy in this case because you cannot fly anything like this route. That area has been totally prohibited for decades.
They are not (nor have ever been, in my 45 year memory) Prohibited Areas. They are Danger Areas requiring a crossing clearance from Plymouth Mil, and you can often/usually get a crossing. They are, indeed, inactive at weekends and you can cross them without a clearance.
Your posting is pure FUD. The truth lies in the AIP.
Your posting is pure FUD
Good to see you back on usual form, Timothy 
Since I got the IR in 2006 London Control have never let me go through them. Perhaps somebody should tell NATS about Plymouth Military
And in 6 years before that, I was never allowed to go through them by whatever ATC I was talking to.
So while not “prohibited” in e.g. the central London sense, they have always been inaccessible for practical purposes. I wonder how many people knew about Plymouth Mil?
This other thing is the apparently universal weekend closure. This is last year’s CAA VFR chart
and now we have (from Jepp Flitestar; I don’t have the 2018 CAA VFR chart yet)
and I checked this in EasyVFR and it says the same. Was this D area inactive every weekend in 2017 and before?
At least in Germany and some other countries, a Danger Area does not require a crossing clearance, so technically it is neither prohibited nor restricted airspace. You might not get cleared IFR through it when it is active, though.
Many UK danger areas can be crossed legally. It is according to a regulation (a “byelaw”) attached to it. No idea where you can find these, however.
I have had London Control route me through D138
but never through the D036-D039 above.
Neither dp these on the UK. There are – strangely enough – danger areas which are acrually prohibited (which is a bit silly) but the Portsmouth danger area complex isn’t one of them.
I wonder where the DCTs come from.
While IFPS reliably checks rules while on airways, it does not do that when usind DCTs that are off airways. It may do so in some cases, but it isn’t universal. Some DCTs are part of standard routes, but it is best to assume that, when using DCTs, you are on your own!
Calling a D-area a “prohibited” area leads to confusion, because there are areas which are properly called that.
There are P-areas, R-areas and D-areas. As far as I know, the UK is unique in requiring the pilot to have a permission to cross an active D-area. Another thing is that you if you are operating as a controlled flight, you wouldn’t get a clearance through an active D-area unless ATC has coordinated with the activity in that area.
Peter wrote:
I wonder how many people knew about Plymouth Mil?
It’s printed in the AIP and quite clear in SkyDemon, why would people not know?
Airborne_Again wrote:
s far as I know, the UK is unique in requiring the pilot to have a permission to cross an active D-areaIs this really required (talking about a VFR flight)? How would I as a foreign pilot know if this is not even mentioned in the AIP?
