Bob,
I stand corrected, although surely, due to the very nature of his work, he would have a higher level of clearance than 'standard' RAF pilots? He was a Special Forces chauffeur, so that would be a bigger target on his back for evil-doers in this country.
Personally, I don't care that he snorted cocaine when he let his hair down a little too much. That's up to him and there's no evidence that it impaired his flying judgement. Taking those substances on to the base was very stupid, although it doesn't make him a bad guy. Trashing his career was a little harsh, IMHO.
Although we aren't in possession of all of the facts which is why I point-blank refuse to judge his character.