Thanks for the replies, that's really helpful. The opportunity to go abroad would be a positive if my son and I could also go with him, but a big negative if he was sent away for months and we were unable to go. (Am I right in thinking that we could go if it was a posting for at least 6 months, but not if it was a 'detachment'? I know nothing about these things!). He's also looking at applying for civil ATC, but the info we read online made it sound as though there is more career progression in RAF ATC - don't know if that's really true or not.