Dixi
Thnaks-bypass was the word I was looking for but could not remeber, the exhausts nozzles on the Speys look tiny in the pics on this thread. And I know things take time but as has often been pointed out the Spey didnt seem to have much development potential which would obviously limit the Tridents growth. Had it been able to push out another few thousands of pounds thrust then perhaps the T3 would not only have not needed a fourth engine but might have given the 727 more competition