I think that what we are talking about now is different from DOC 4444
DOC 4444 only requires one of the aircraft to be more than 15nm from the VOR.
Our operations manual specifically states:
"15 degrees between same direction, outbound aircraft ......."
and
"15 degrees between opposite direction aircraft provided they will pass at a point more than 15 miles from the facility"
To me indicates that firstly there is no provision for the situation where both aircraft are inbound but not opposite direction (perhaps included in another part of the requirements?)
Secondly, making a requirement that the opposite direction aircraft will pass at a point more than 15nm from the facility would mean that depending on relative speeds, one aircraft will have to be much more than 15nm from the facility so that when they pass, they are both more than 15nm.
Going back to my original stretching of the DOC 4444 words, it could not happen using this version of the sep standards since the pass would take place within 15nm of the VOR to have the sme situation with 1 B747 1nm from the VOR, the other would have to be some 16+16 = 32nm from the VOR so that the pass will happen between 15 and 16nm from the VOR...........thus the head to head separation is more than twice what DOC 4444 says and sounds far more reasonable.
Regards,
DFC