Wrathmonk, as are UK standby SH aircraft. And they are called out about as often. Doesn't mean you need 6 Sqns of AD assets to generate a pair and and a spare does it? It's only called upon rarely, but when it is it could be of national interest - just like the national Sby RW assets. So, Typhoon is multi role and that justifies it? It's not more multirole than a CH47 though, especially in a UK homebase scenario.
Melchett - the original plan was Merlin 3/3a to CHF to be backfilled by 24 CH47F (UK Mk6). A 'peace dividend' has already been taken and the buy reduced to 14, hence why the original plan to re-equip 28/78 with Chinook needs to change; combined with the smaller Puma 2 programme there are potentially 2 Sqn plates at risk.