Thanks for sharing this news with us. Echoing many, his work and the impact it had cannot be under-estimated to the development of the hobby and sport.
I have to agree with the sentiments above. John was the face of MBUK when I first picked it up in 1990. He wrote all the tests & tech/mechanical articles if I remember correctly. I'm sure we all read those pages & added to our knowledge. Such sad news, I wish him & his closest family peace & tranquility at this time.