UK specific airspace modification

[kungfuman]

I've completed my modification of UK FIR ATCC sectors for FS9. It may work in FSX, but has not been tested.

It contains Scottish FIR sectors almost exactly as they appear in the UK AIP, including correct frequency data. With the London FIR I have tried to cater for airway traffic, as lower level flights are generally within 30nm of an airfield with its own approach frequency (which fs9 refers to instead of what's in this file). Therefore in this region I have retained the Manchester Control sector, but changed its geographic boundaries. I have also edited the London Control sectors as required.

The file affects all UK airspace that meets either one of the following criteria:

1: All airspace that is greater than 20nm/30nm from the nearest airport with an approach or departure ATC channel.

2: All airspace above 10,000 ft MSL.

The file goes in the scenery\world\scenery folder (alongside the default "Center" data file, and all your flightplan files). FS will read the "Center" data from this file instead of the default file when you fly within UK airspace. In two and a half sectors (out of thirteen) fs9 still reads data from the default file, but this doesn't actually detract from the "user's" experience. It just means that the default frequency will be used in that area rather than the modified frequency. Advanced users may want to incorporate my modification into the default file to overcome this minor effect. But as I said, it causes no problems.

If the administrators are happy, I can attach my file here for other MAIW users. The file is only 11kb, and I won't broadcast it's location on other fora.

On a related matter, I have already changed my lower airspace (upto 10,000ft) using AFCAD. England has a very high density of airfields, so normally light aircraft - or any aircraft in the lower airspace - will recieve an ATS from a nearby Approach controller. By creating afcads for many of these airfields, I have included a relevant approach frequency and callsign (not necessarily the airfield's own ATC - especially if it's a quiet airfield) so that wherever one is flying below 10,000ft, one is always in contact with the appropriate controller. In certain areas that are further than 20nm/30nm from the nearest airfield, I have used strategically placed "null" afcads that contain only a geographical position and the (approach) frequency and callsign of the appropriate ATS unit for that area. It is actually possible to create LARS sectors with great precision in this manner.

[Fastair]

WOW....outstanding, I would be most interested in this please.

Thank you in advance for its release....

Reagrds,

[kungfuman]

No objections recieved, and anyway I think only a couple of people will be interested in this one. So here you go. As I said, just pop it into your \Scenery\World\scenery folder.

No more Manchester Control in Wales and the West Country, more realistic com frequency allocation all over the UK, and also London FIR sector north of the Isle of Man has now been delegated to Scottish Control.

I hope you find it to be a positive improvement on the default.

[Firebird]

Appreciated.

[ricki429]

wow your really getting your self noted - quality stuff coming from you keep it up mate

[HC136TH]

Thank You!

[kungfuman]

Very kind of you Ricki429

I decided I like to share...

[Fastair]

Many thanks indeed...

Regards,

[kungfuman]

Just thought I'd bump this in case anyone who'd appreciate it missed it first time round...

[Greg]

Any chance you could tell us how you managed to do this?

I am a military area controller in Belgium in real life, and I really really hate how the Brussels FIR/UIR is subdivided in FS9. I'd love to learn how to make a file like yours for Belgium as all the relevant airspace knowledge is in my head already

Greg

[kungfuman]

What, precise coordinates and all?!? (In your head, that is...)

Basically, decompile the bvcf.bgl (its in the Scenery/World/scenery folder with the flightplan files) using IIRC the BGL2XML program from possibly Scruffyduck.

Edit the relevant sections and/or create new sections by inputting the correct co-ordinates and frequencies and following the xml syntax.

Recompile using the FSX BGLCOMP. Place back into your Scenery/World/scenery folder, BUT MAKE A BACK-UP OF ORIGINAL FILE FIRST!

If anyone reads this and subsequently ruins their life, their computer, or just their FS9 installation:

I am not to blame for your own voluntarily undertaken mis-adventure

If you want to share your airspace changes, then only compile the relevant xml sections into a bgl, otherwise we will end up with many people working in parallel, releasing "global" bvcf files that don't carry the modifications that others are currently working on forward (and vice versa). Also, this would constitute a copyright infringement of microsoft code if I understand correctly.

Hence my file is uk_bvcf.bgl, which operates alongside the stock bvcf.bgl. FS9 reads my additional bgl when in the appropriate virtual geographical location instead of the stock bgl, but this is probably just a happy coincidence related to the naming of the file. I don't know how to guarantee that FS9 will look at the Add-on bgl, so if you were to release a correction for Belgian airspace, I would probably copy your modified section into my stock bgl myself, thus guaranteeing that your edits are read. Its what I did with my own. Even so, if you share your work, just share your modified sections. It should be upto the end user to choose whether they will insert the modifications into the stock themself. The alternative could end up in total chaos.

You really need to know what you're doing, or be prepared for the worst, if you want to start messing with stock files (I am in the latter category ).

Let me know how you get on

[Greg]

Alrighty thanks for the info. Sounds fun!

Well of course I meant the subdivision of the airspace and the respective sector at Brussels, Maastricht or Belga Radar, but I know where to find the right co-ordinates

Once I've figured out how to do it I'll have a look at the naming and priority thing. Isn't it possible that FS9 looks for other bgl files before it loads the data from the stock bgl, like it does with AFD files?

Oh and can you explain why you're using the FSX bglcomp i.s.o. the one in the FS9 SDK?

Thanks mate!

Greg

[kungfuman]

I think the problem with the naming thing is that the stock file exists in the same folder as the add-on files. I am only guessing here, but I cannot see any obvious difference between the stock file and the modification. Its just another file in the same folder.

In other cases (AFD files), the stock data is in a different folder to the add-ons/modifications, and FS9 has priorities set along the lines of "look in this folder first, then look in that folder in case there's some relevant info to be used instead". If I am correct about this, then such a process would not be able to differentiate the stock from the modification in this case - instead just using the first thing or last thing it "sees". I am totally out my depth with this. I know nothing.

I noticed that the stock FIR sub-regions are defined such that they do not geographically overlap, with maybe a dozen or so yards of unassigned space seperating them. I did not bother investigating this, but followed suit in my own work just in case an overlap (or maybe just a co-incident line or point) would cause problems. I also did not investigate vertical limits, although this could be of interest for constructing TMAs and the like.

The FS9 BGLCOMP was not released with the redesign of the bvcf.bgl in mind, therefore compatibility was not considered. It seems the design team had already moved on to the newer format by this stage of FS9 development. Hence you must use the FSX BGLCOMP. Annoying as this may be, it does work.

Hope that helps a bit.

Good luck,

Dan

[ricki429]

Hi Kungfuman,

Thanks for your upload! I am doing a Salisbury Plain package. The plain has a single frequency called Salisbury Ops, so i was thinking i could add a 'center/control' area accross the plain and somehow using voicepack to say Salisbury ops. I presume that the way you have altered the file would work for what i want to do.
Is this possible? I think i can work out how to assign the area but its how to make a center/control and how to assign the names - do you think you could help at all?

Thanks

Rick

[kungfuman]

I can try.

But what I suggest may not be quite what you're trying to achieve. A control area will mean that high altitude civilian AI aircraft (that travel along geodesics rather than airway routes) will stray into the area, being handed off to "Salisbury Ops" as they do so. You will hear this if you are transiting the area, or if tuned into Salisbury Ops, you will hear them communicating with these civilian airliners. This strikes me as an unwanted (unrealistic) experience in FS9. Therefore I suggest the following:

Firstly, you don't need to do anything to the bvcf.bgl. What you need is afcad.

Give Netheravon an approach frequency of 122.75MHz, with the callsign "Salisbury Ops".
Give Thruxton an approach frequency the same as Boscombe Down, with the same callsign ("Boscombe", probably).

Finally, you need to create a null afcad to the North East; I suggest the disused airfield at Membury, where you may want to place some apron polygons to give the impression of disused runways. Refer to Google Earth. However, you need not create any ground scenery features at all. Neither is it necessary to locate the null afcad at an airfield or related facility. All you need do is give the afcad a unique location, title, ICAO-type code, and an approach frequency. I suggest that you enter the primary approach frequency that you have in use at Brize Norton (that is, the approach details that appear highest in the "Comm Frequencies" list), with the same callsign (if you have the default EGVN, this will be 127.25MHz, callsign "BRIZE"), as this would be the most likely ATCC you'd be in contact with in this area. Alternatively you could enter the primary approach details of Lyneham, although you may feel that this will extend the area in which you are controlled by Lyneham too far East. IIRC, one would be more likely to receive a LARS from Brize than Lyneham, even in this area.

Now draw two lines on a map, one equidistant between Boscombe and Netheravon, the other equidistant between Thruxton and Netheravon. This line will form a slightly skewed cross. The North West quadrant of this skewed cross is the area in which aircraft will be under the control of Salisbury Ops. The other three quadrants will be under the control of Boscombe Approach. The Salisbury Ops sector will extend North East to a line equidistant between Netheravon and Membury, North West to a line equidistant between Netheravon and Lyneham, and West to a line equidistant between Netheravon and Bristol. This pretty much defines the area in which aircraft would be under the control of Salisbury Ops. Additionally, it won't have the unwanted effect on the high altitude r/t behaviour of civilian AI traffic.

All you need do now is create a "Salisbury Ops" callsign, probably with EditVoicePack. I haven't ever done this myself, but I think it's fairly straightforward, if a little time consuming (you have to create the callsign with each of the eleven or so voices, I think).

[kungfuman]

Another thumbs down to creating a control sector here: As the Salisbury area lies within a FIR sector, you would have to do some additional editing of the current London sector, splitting it in such a way that the Salisbury area would no longer be an "island".

Also, the callsign cannot be Salisbury Ops with either the bvcf edit or the afcad method. FS9 will affix the word "Control" to a FIR sector callsign, or "Approach" to a afcad frequency callsign. Therefore the callsign you must enter for the Netheravon afcad should just be "Salisbury", not "Salisbury Ops".

[Greg]

I noticed that the stock FIR sub-regions are defined such that they do not geographically overlap, with maybe a dozen or so yards of unassigned space seperating them.

Yes there's a warning for overlapping boundary areas in the FS9 bglcomp readme. This makes stuff a bit more complicated.

I wonder where terminal control area information for aerodromes would be stored, because the bvcf.bgl file only contains the FIR/UIR information. Could it be that FS9 just takes a certain default radius around the aerodrome? I noticed in the bglcomp readme that one can make approach and even prohibited and danger areas with xml boundaries, but I wonder if the bvcf.bgl file would be right place to store that info?

It seems like an almost unexplored part of FS9 so far, but I guess you'd need to be a real pilot or controller to notice that the default areas are totally off so most simmers don't really care.

Greg

[kungfuman]

Well, I'm not a real pilot or a controller! Done some gliding though

But having been involved with general aviation due to my fathers light aircraft hobby, and having thus been flown all over the South of England - and even Belgium (Oostende) too - I appreciate how wrong the control sectors are. It really grates being handed over to Manchester Control when in Cornwall! That just ruined it for me. So I had to do something about it.

My thanks go to Richard Greany from New Zealand Flightsim Forum for his guidance.

When flying in FS9 above 10,000ft, you will always be under the control of whatever "Center/Control" facility is specified in the bvcf.bgl for your location. As you approach your destination, this will remain the case until your descent approaches 10,000ft, wherupon you will be handed over to the approach control facility as specified by the nearest airfield to you that has an approach frequency listed in its AFD, whether this is your destination airfield or not.

Under 10,000ft, FS9 refers to its AFD - including Add-on Afcads etc. - for its Approach control sector deliniation, not the bvcf.bgl. This is one thing I have tested extensively. Under 10,000ft, you will always be under the control of the nearest approach facility, unless you are more than 20nm from it, whereupon you will be under the control of whatever is specified in the bvcf.bgl. I have also found a couple or so cases where the range of an AFDs influence, that is, how far away you have to get from the Approach control facility before you're handed of to the "center" is 30nm. But this is unusual, and I don't think I found out the reason for these facility's extended range. Nevertheless, I am certain about Approach control sectors being defined by which facility is closest to the given location - upto a maximum range of 20nm (occasionaly 30nm) and a max altitude of 10,000ft.

Unfortunately, there is also a bug: many facilities, often military, have been given a fictional/incorrect approach frequency of 123.3MHz. This appears to confuse FS9. Often I have been happily flying along in one part of the country, only to be handed over to a military controller from a different part of the country - but always on this frequency. I eventually overcame this by searching out all AFDs with this frequency listed as an Approach frequency and made many updated afcads with the offending r/t channel deleted. It worked! Always be suspicious of 123.3MHz. Note which facility you have been handed over to, and amend the offending channel in the relevant afcad.

It is due to all this that I can create an accurate Lower Airspace Radar Service (LARS) network in the UK. Sectors below 10,000 ft can be accurately defined by strategically placing "null" afcads - what I call an afcad I'm not using to create visual elements with. If you read my reply to ricki429, this is what I am suggesting he does. By creating a geographically located approach frequency in the Membury area, he will be effectively creating a straight line boundary equidistant between his Membury afcad and Netheravon. This line will extend in either direction until it becomes closer to the geographical location of another approach control facility.

You see how it works?

I only wondered whether it might be possible to use the bvcf.bgl to define "Areas" rather than "Zones" - ie for airspace that is above 10,000 ft. Below 10,000 ft, FS9 will always use the local AFD as a priority over the bvcf.bgl

[Greg]

Okay I get the point I think. Thanks for the insight Dan, very interesting!

Maybe i.s.o. creating "null" AFCADs to make a LARS type airspace, one could expand the influence area of an aerodrome's approach by making boundary areas with the "APPROACH" tag i.s.o. "CENTER"? There are no such areas in the default bvcf.bgl, but it's worth investigating.

In the BAF we use 123.3 as the VHF frequency for PAR approaches. If I remember correctly from my days as an approach controller it's the common NATO VHF talkdown frequency, and that would be the reason why many military aerodromes have it listed in FS9.

What's with the meter thing for vertical limits by the way? Did Microsoft anticipate on an invasion by the Chinese?

Greg

[kungfuman]

AFAIK, you can mess about with bvcf.bgl as much as you want, but FS9 will not look at it unless you are above 10,000 ft, or are at least twenty miles from the nearest approach frequency equipped afcad (stock or add-on). It's a matter of layers of priority.

But please try and prove me wrong! Your findings will be read with interest here...