ferris et al,
The point is obviously lost on you - if you work to the exact letter of an isolated paragraph of DOC4444 without taking the consequences into account, you end up with what I said.
The point is that one can not extract a small paragraph from DOC 4444 and use exactly what it says (which I did) as the sole basis for establishing a certain separation standard otherwise one can have someone using the exact words to do something like I described.
So that there is no doubt, an aircraft flying outbound along the 270 radial is diverging from an aircraft travelling outbound on any other radial.
Similarly, an aircraft inbound on the 270 radial is converging with an aircraft inbound on any other radial.
DOC 4444 sets a minimum angular difference there is no specified maximum.
Same direction, opposite direction and crossing tracks are defined with respect to Longitudinal Separation. That is not what we are talking about here.
The debate for years regarding that paragraph was if the aircraft had also to be diverging. Many providers required the aircraft to be diverging. With such a stance one could never end up with the situation I described.
Separation is established according to an array of issues which can not be established based on a single paragraph from one book.
That is what the planning manual etc etc etc provides the guidance for.
Regards,
DFC
Last edited by DFC; 18th May 2009 at 17:49.