Reference "... and for the second and third flights as 'Butt', which I suspect is a mis-spelling as I think I remember he was of Indian origin..."
I beleive your spelling to be correct as I think this refers to the then Warrant Officer DH Butt (later comissioned?) who in around 1983 became the first VGS instructor to reach the 1000 hour target on the Venture Tmk2 with 642 at Linton.