Perhaps the occasional inefficient clearing of the hold (aircraft coming off with 15-20NM gaps, vacant level bands of 3000' to 4000' feet with traffic sauntering slowly down instead of the more regimented and efficient holding management seen in the likes of the London TMA where things bump down naturally as levels are vacated and a tight pack of aircraft and level useage exists)
might be part of the reason that ScACC prefer to try and go for a sequence instead of everything to the hold. A few of us have been bitten.
And then there's the non existent reporting of vacated levels by APC (as per the MATS Part 2s requirements) which makes ScACC uncertain as to what levels have been freed up.
The 'book' says that ScACC can sequence 3 simultaneous arrivals (that's sequence, not to the hold) with subsequent arrivals for that sequence then being put to the hold. This is open to interpretation because if the 3 arrivals are far enough ahead to allow the Standing Agreement conditions to be met by following aircraft then I believe the next arrivals form another new sequence and would not expect them to hold unless directed by APC to do so (provided I give the minimum spacing and appropriate vectors or speed control to maintain or increase it).
All traffic should be vectored to the hold or follow the STAR and then we at the airport can decide who comes straight off or needs to hold (part of our standing agreement but hardly ever practised by Scottish).
A disjoint here - because the ScACC Agreement states that the aircraft should be routeing to the holding fix (not necessarily on the STAR as long as it gets there in the end)
OR on a heading 'towards' the holding fix. Note the 'towards' which is again not as black and white as to take the aircraft directly to the fix on a heading. This provides the leeway to have 2 aircraft on parallel headings 'towards' the holding fix area since if one was vectored to the fix then the other could not be and still maintain separation. As most traffic is handed off about 10NM or more before the holding fix, then APC still have the option to take the aircraft off the heading and direct to the holding fix if that's a better plan for them.
Just trying to show that, as with most things ATC, the blame is never solely on one side or the other. It's a team game, so get talking with your opposite numbers or visiting adjacent units to resolve your own personal gripes and improve your knowledge folks
