To fully explain what I meant with my proposal, I will now say wich aircrafts should have enlarged FAA ( maybe renamed for Naval Air Force ):
Sea Typhoon ( obviously no land based Typoon for Britain ITTL )
E-2 Hawkeye ( for carrier AEW ) ( I'm not sure does UK ITTL needs land based AEW aircrafts like Sentry )
Sentinel R1 ( land based, obviously, but since his main mission is to send datas to FAA Sea Typhoons, I put him in FAA )
Merlin ( for SAR/CSAR in aircraft carriers, and maybe also for SAR in UK- if not offsourced to private contractor )
C-2 Greyhound ( for COD )
Merlins for ASW ( I would love to have all-Merlin ASW fleet on destroyers and frigates )
For OPVs I would use AW.109 or 149
For air landing of Royal Marines I would use Merlins and AW.149.
All training aircrafts would be in FAA ( Tutor, Tucano, Sea Hawk/Goosehawk ) and FAA would conduct fixed-wing training for both Services
OTOH in Army Air Corps I would put:
All current Merlins, Lynx, Chinook, Pumas that serve for tactical transport of Army units
All UAVs, from Hermes to Reaper
All transport aircrafts like C-130, Globemaster, KC-330, because their main duty is to transport land forces
And finaly, all training helicopters ( so FAA would conduct helicopter training for both Services ).