My god, what a shock - last I saw him he seemed in the very best of health.
I'd never had the privilege of working closely with Keith, but had got to know him on first name terms over the years, and enjoyed once or twice a year a long technical discussion (actually usually a goodnatured argument lasting an hour or so) on some topic or other.
I recall one in particular where he was explaining at great length why he thought that the simplistic safety factors used in most engineering standards were unnecessary - because if you carefully stress-analysed every bolt, rivet (and I seem to remember, individual screwthread) on an areoplane there's no need for that sort of thing. His entry in whos who showed his hobby as "recreational stressing"!
He was a truly brilliant engineer, a really nice chap, and somebody who had done far more than most to support the British light aircraft industry. In particular his rescue some years ago of Pegasus Aviation, and his more recent acquisition of Mainair Sports and merger of the two companies were inspired decisions (which I think actually made him some money).
A genius and visionary, without whom British light aviation would be far poorer.
Whilst I had no contact with him in that sphere, I believe that his influences on the engine and motorsport industries in this country were no less significant.
A great loss. Good luck restressing the pearly gates Keith,
G