@jan-aerts
According to the FAQ:
Q: I am the defending player in a naval battle, where my carriers were destroyed. I still have a few fighters/tacticals left. What happens to the aircraft?
A: If the Defender lost Carriers containing aircraft, these aircraft have a movement of 1 to find a suitable landing spot. If they are unable to do so, they are eliminated.
Also, on carrier MAP:
Q: aircraft on carriers can act as if on Maritime Air Patrol, but if you decide to do so, do you also have to un-MAP then (and thus wait a turn), in order to use them for other purposes?
A: No. That is why the rule says “may act as if…"