LoLevel
Nope. it's TAS based, since G/S is a constantly moving feast. And for a minimum of 10 minutes, no speed differential is specified.
2 Sheds
Yes, it's radar derived as they enter the Atlantic, HOWEVER, procedural separation could be based on aircraft reports alone, for example in domestic procedural separation. In fact, mid Atlantic, that's exactly what we use for obvious reasons
On your second point, strictly speaking, yes the PA28 and TriStar
ARE separated, ICAO decrees they are separated up till the point where 10 minutes no longer exists. For aircraft at the same level and on the same track, the
MINIMUM separation is 10 minutes. If you have the
MINIMUM, then you're legal until that is lost. Not sure that anyone would be silly enough to apply it though without a different plan in the case you quote. !!
Otherwise, if you think about it, a prop departing from Europe for Iceland has immediately lost separation with the B763 departing the Middle East for the USA at the same level on the same route because the B763 will eventually catch it in about 4 hours time !! I think not
You're trying to link distance into a longitudinal time separation, which is totally irrelavant. Two PA28's @ 120 Kts and 10 minutes apart (20NM in still air) are actually just as separated as a PA28 and an L1011 10 minutes apart in terms of time, even although there is 80NM between the second pair.
Dig out the Doc 4444 guys !!
------------------
10 West
UK ATC'er
[email protected]