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Nikolas
22nd Nov 2022, 06:14
In your country, do you need to separate from prohibited, restricted and danger areas?
If so, what kind of separation do you need?
If no, why not?

LuCst
22nd Nov 2022, 14:45
Yes,

Vertical separation no less than 1/2 of the applicable vertical separation minima, i.e. 500ft to areas up to FL285 and 1000ft to areas above FL285.

Lateral separation is a bit less straight forward:
None required for IFR in Class G or VFR in any airspace class.
1NM to areas wherein there is no flying activity (or where any flying activity is limited to UAVs at or below 120m AGL).
2.5NM to areas wherein there is military flying activity controlled by fighter control or another ATSU.
3NM to areas with flying activity that is not controlled by anyone (soaring sectors, military flying without fighter control etc.).

Equivocal
22nd Nov 2022, 20:33
I was involved in such things some years ago (probably around 15 years). At that time there did not appear to be a standard and different states did things in different ways, and not always consistently within a single state. We developed a standard for the country I was working in at the time and we focused on the design of the prohibited, restricted or danger area and ensured that there was a minimum buffer inside the area vertically of the appropriate IFR separation (which was always 1000ft) and a buffer horizontally of the greater of either the radar separation appropriate to other aircraft outside the D/P/R area, or the maximum horizontal visibility required for VFR flight at any time outside the D/P/R/ area. By doing this, any aircraft that remained outside the D/P/R area was at least the separation that an IFR flight would expect or a VFR flight would be able to see aircraft inside the D/P/R area. We added a bit to the buffer - I can't recall by how much - if the area would be used at any time for high-energy manoeuvers.Vertical separation no less than 1/2 of the applicable vertical separation minima, i.e. 500ft to areas up to FL285 and 1000ft to areas above FL285.
Lateral separation is a bit less straight forward:
None required for IFR in Class G or VFR in any airspace class.
1NM to areas wherein there is no flying activity (or where any flying activity is limited to UAVs at or below 120m AGL).
2.5NM to areas wherein there is military flying activity controlled by fighter control or another ATSU.
3NM to areas with flying activity that is not controlled by anyone (soaring sectors, military flying without fighter control etc.). That is interesting - is it an agreed standard?

LuCst
22nd Nov 2022, 21:03
That is interesting - is it an agreed standard?

It is the standard used by my ANSP for national P/R/D areas as per our MATS pt1.

We have some international D-Areas that border us and to those we have a blanket 2.5NM radar reparation in the LOAs regardless of what goes on within the areas. One of our neighbours has different vertical separation minima however their areas are presented to us with an added buffer which allows us to use "our own" minima and still be safe.

chevvron
23rd Nov 2022, 10:06
In your country, do you need to separate from prohibited, restricted and danger areas?
If so, what kind of separation do you need?
If no, why not?
In the UK you just remain outside the lateral and vertical limits as shown on your charts.

whowhenwhy
23rd Nov 2022, 11:17
It is the standard used by my ANSP for national P/R/D areas as per our MATS pt1.

We have some international D-Areas that border us and to those we have a blanket 2.5NM radar reparation in the LOAs regardless of what goes on within the areas. One of our neighbours has different vertical separation minima however their areas are presented to us with an added buffer which allows us to use "our own" minima and still be safe.
That 2.5 nm separation is down to ICAO Doc 4444 which requires aircraft to be vectored no closer than 2.5 NM to the edge of contiguous volumes of controlled airspace. The theory being that if that is followed on both sides of the "line", then you will have 5 NM lateral separation between flights.

whowhenwhy
23rd Nov 2022, 11:18
In the UK you just remain outside the lateral and vertical limits as shown on your charts.
You're right Chevvron but we can do that because the design of the airspace includes a buffer within it.

Equivocal
25th Nov 2022, 09:51
We have some international D-Areas that border us and to those we have a blanket 2.5NM radar reparation in the LOAs ...As whowhywhen says, 2.5 mile buffer works ok if you know that traffic inside the reserved area will also stay at least 2.5 miles from the edge and I think Doc 4444 assumes that traffic on both sides are under positive radar control (and that the standard radar separation is applicable).
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LuCst
25th Nov 2022, 11:37
As whowhywhen says, 2.5 mile buffer works ok if you know that traffic inside the reserved area will also stay at least 2.5 miles from the edge and I think Doc 4444 assumes that traffic on both sides are under positive radar control (and that the standard radar separation is applicable).
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Indeed, not sure why that 4444 para was brought up here as I am confident most of us are proficient with fundamental ICAO procedures. As the 2.5NM in my example also apply when the R/D areas aren't directly on the border but further downstream (and also not only under vectoring) it isn't really relevant to the original question which was specifically about P/R/D areas and not separation to adjacent airspace.

Equivocal
25th Nov 2022, 14:06
not sure why that 4444 para was brought up hereBrought up here, I guess, because your ANSP's standard sounded like it might be based, in part at least, on that procedure. Your original enquiry was about 'separation' between two pieces of airspace - which is not well standardised - and something that might be relevant to the discussion. I simply pointed out that the Doc 4444 reference was based on certain assumptions which may not apply to the situation you described.

But the criteria used by your ANSP is interesting - does it actually provide assurance of true separation between aircraft operating each side of the reserved airspace boundary?