BBF,
A few years ago, a C152 pilot flew into the mountains of North Wales. He was en route from Caernavon to Shobdon and, immediately before this, he had demonstrated sound airmanship by returning to Caernavon to take on enough fuel so that he could go round the mountains because of the clouds over Snowdon.
Although he survived the accident which, unfortunately, his passenger didn't, he is unable to remember anything about it. Months of speculation on Pprune and elswhere and an AAIB investigation were unable to explain why he flew into a mountain he must have known was there.
However, as far as I know, no-one has found it necessary to convict this pilot of anything. In the civilian world it seems that we are grown up enough to accept that we cannot explain everything and neither do we always have to.
I have never forgotten Wratten boasting to Paxman on Newsnight about how he did not shrink from his duty to find the Chinook pilots guilty of gross negligence. It seems a pity that he wasn't as diligent when it comes to the airworthiness of the equipment under his command.