Why three carriers do not require three air wings

Would a Royal Navy with three carriers need three complete carrier air wings?

No. Two operational air wings plus a training and support pool would match the likely availability of three carrier hulls.

A three-carrier fleet would not normally put all three ships to sea with full air groups at once. Under British readiness and maintenance patterns, the force would need aircraft for two operational carrier air wings rather than three. A training and support squadron would still provide additional aircraft and personnel that could reinforce a third ship in an emergency. This distinguishes the number of carrier hulls from the more expensive question of how many complete air wings must be sustained.