What very sad news but thanks to Dave Fry for letting us know.
I knew Dewi for over 30 years from the days when he worked at Boscombe Down as the Aviation Medicine specialist who did all of our aeromed training; many a hypoxia chamber run livened up by Dewi's Welsh humour! During his time in that job we flew together in Tornado F2, Hunter and Hawk as he took the opportunity to fly whenever he could, and he really understood what we did.
We kept in touch and for many years he was my AME and I renewed my medical with him last year only a couple of days before he retired. They were probably the longest medicals that I have ever had anywhere because it took a good 2 or 3 hours to catch up on what we and mutual friends had been doing over the previous 12 months. And then he would fill in the declaration form seemingly knowing my weight and number of units of alcohol consumed per week by telepathy! Bur he was a rare breed in that he was a doctor who I trusted and felt that I could always get good advice and help from on health issues without fearing for my flying category.
I am so glad that I have very happy memories of Dewi's wonderful personality and friendship. He was a truly delightful person.