Thanks everybody for your advice. I have spent a fair amount of time cold calling ops departments seeking advice and get the impression that any form of formal training is a plus. The FAA License is probably the most sensible route as it appears to be highly regarded globally. I've sent off to all the schools recommended here for their glossies and will decide from there. At least I have an advantage in that being military the RAF gives me 7 weeks for training courses in my last 12 months of service and a few sheckles to put towards it too. See you all out there sometime.