Lofty - I might just have broken the OSA in giving away performance secrets! The FAA, like the RAF, wil just have to get used to fewer Sqns. I don't agree that the FAA has a 'critical' point looming - there is still a rump of ASW/ASuW Sqns. I thought the idea of the common cockpit between Mk2 and Mk4 Merlin was to enable crews to move between roles (as in SK days).
NAB-stop being so precious. A CH47 only takes up an extra half spot or so compared to Merlin, for which you get 4 or 5 times the "punch per deck spot", almost total wind tolerance (I've landed at 30kts downwind on the CVS - the ships nav was quite happy he didn't gave to turn....) and the ability to lift Royals' heavy kit. Ergo, any future 'war' TAG will inevitably include Chinook. I know it's not all about QEC, and so does the RN - that's why the T45 and T26 decks have been designed to be CH47 compatible.....