I've just got back from Northern Ireland so have not been able to keep abreast of the CM in detail but, thanks to Dick, I've got some idea of what's been going on. Here are some thoughts based on what I've seen and heard over the last three weeks.
One. There is no earthly reason why a pilot cannot be given a level below the SA if he seeks to go low level. He wouldn't accept it if he was IMC. He has his own - in this case - MVA/Route Abort Altitude procedures to get him out of a hole if needs be.
Two. Fifteen minutes before the (calculated) time of the accident the forecast was 3 oktas of cloud at 3000 ft which means that there were five oktas of clear blue sky hence it is probable that the lead was in visual contact with the ground.
Three. Four independent (civilian) witnesses, in differing locations in the vicinity - and at the same time - each saw "two twin finned ac in close formation", travelling from East to West. None of these people are related and, as far as we know, have had no contact with each other.
Four. Ben McDhui, and other peaks in the area, had their tops obscured by cloud with a base of 3000 ft (forecast) - the witnesses observed the ac below cloud and stated that the peaks were, indeed, obscured!
Five. If the ac were below a cloudbase of 3000 ft, they had busted the assigned level of 4000 ft! Unfortunately the lead pilot cannot answer that fundemental question.
See you next week Spot 'n Sue - I wouldn't miss the outcome for anything.
LOTSALUV,
Al & Diane