Biggus,
I think that we are in danger of taking this thread off at a tangent. All I am trying to say is that the speed of any replacement MPA is only one of a number of factors that has to be taken into account - and that it, IMHO, is not the major factor. I would rather see a slightly slower ac, with the correct kit, crew constituion, training and tactics etc than a very fast ac unable to complete the task.
That said, in the good old days when the SAR helos went out in twos, if the topcover Nimrod went u/s on start or ONSTA, they still went. There was nothing that I was aware of on RS60 (or quicker) to provide any other support. If you know of something else, I'd be interested to hear of it - off line if necessary.
Duncs
PS. Nice link. I was aware of HMCG; I was thinking along military lines - oops, that will teach me. However, it does illustrate that point that, if the FW goes u/s, the helo will crack on and do the job; albeit with less of a warm fuzzy feeling that they are being looked after.