Hiya Mike,
I do know that they are a rare breed of pilot these airshippers. Past boating, helicopter and balloon experience is useful...it's combines all three disciplines. Then to get the licence, you must be able to pay for a fair few pairs of hands to handle the rope stays. Not a poor man's game by any means.
I think there's a place up Leicester way that does them. Curiosuly Cardington still hs a R-area surrounding it but no airships.
I'm quite surprised too that no-one ever gets into ballooning. I imagine it must be accessible, surely?