He used to hang out in the Usenet soaring group which I read and occasionally posted. I recall having a discussion with him about Ralph Merkel's contribution to public key cryptography (If I recall correctly, Hellman said Merkle's paper on the subject was allegedly difficult to understand, so wasn't initially given the recognition it deserved.) I had met Ralph very briefly at a Nanotechnology Foresight conference about twenty years ago.
Another glider pilot on that newsgroup, a doctor, was a young CFIG back in the 70s when he helped instruct actress Susan Oliver in gliders. She was the "Green Girl" in the Star Trek pilot episode.