At major airports you need an ADA (authority to drive airside) issued by the airport operator
(as per Airports (Control of On-Airport Activities) Regulations).
AFAIK they all require that you have a valid State licence on your person as well and produce it on demand.
As for ASICs, they used to be good for free entry at some nightclubs on some sort of 'industry' contra-deal, but I haven't tried it in a while. People who were female and looked like an FA used to have more success than others
