This is indeed sad news.
David was singlehandedly responsible for getting me into flying and saved me from being an accountant. Might've made more money in the latter but without any of the fun so I've got a lot to thank him for in several ways.
David was the pioneer of "motor home" living during his training at YMMB, much to the amusement of many. One of heaps of good stories that can be told about such a nice bloke.
My deepest sympathy to Jill and family.