Aispace buffer 1

18.02.2010

Submission:

As the ICAO PANS-OPS documentation doesn't specify or address the concern of using a proper value of protection between the floor of a controlled area and the instrument approach protection areas I have a few relevant questions:

1. What is the clearance applied (or should be applied) to the lowest part of a controlled area (TMAs) when calcualating MRVA for radar vectoring?

2. What is the clearance applied to the lowest part of controlled areas as far as instrument approach protection areas are concerned? Minimum protection of 500ft, 1000ft or more?

3. What amount of clearance should be applied when the procedure over-flies Danger or Restriction areas, TSAs, TRAs or ATZs?

Any ideas as to the requirements that should be met in considering the correct values of clearance to be applied would be appreciated.
Does anybody know the ICAO references concerning this?

Vortilon, procedure designer – Poland

Answer or Commentary:

I.W

I am not sure but I don’t think that this is specifically covered in ICAO documents.

Most of it comes down to “Best Practice” and varies from country to country. Some countries (UK) even have an official “buffer policy” document. Following are some ideas.

1.

The nominal track of the procedure is within controlled airspace and 500 ft above the lower limit. The nominal track should also be 2nm away from the lateral limit of controlled airspace.

Some countries specify that it is not just the nominal track but also the primary Pans-Ops obstacle protection areas that need to be clear of the buffer area.

2.

The instrument approach should be within the CTR (controlled airspace) and so it is not a problem.

3.

This, once again, seems to vary from country to country. Some countries use zero tolerance between the nominal track and the Danger/Restricted areas while others use 2000ft vertically and 5 nm laterally.



As I said, it all comes down to “best practice” and if the lateral and vertical buffer limits are infringed a risk assessment should be carried out. Such an assessment should take into account the type of operations that will be carried out in the adjoining airspace.

Can any of the other procedure designers out there give a reply?


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