When can I scramble?
Up to three fighters/tactical bombers can be scrambled into each sea zone adjacent to a territory that contains a functional airbase.  Any aircraft that are used in this way cannot be used for any further combat operations for the remainder of the round.  You may select units to be scrambled after the attacking player has finished all of his combat moves and you may do so any time the appropriate sea zone in attacked by either air or sea units and that included defending the territory against amphibious assaults. 
An example is sea zone 109 and 110 are adjacent to United Kingdom territory.