Aircraft are complex, each new one pushes the frontiers of knowledge & understanding, things going wrong has to be avoided - time, money, many people, lots of thought … and John played a significant part …

For a year or two, John’s desk was just behind mine, so we did sometimes talk … and his role meant we inevitably bumped into each other, now & then … as also, after we retired, at occasional get-togethers ... and e-mail conversations, from time to time, often as a result of thoughts that led to a desire to know what he thought of this or that ...
best wishes

Chris