Originally Posted by
vascodegama
There was no C1 version .
Quite so. K1, KC1, C2 and C2A. However, in the very early days of RAF service, the ex-ba TriStar 500s were known as Tristar C1 before they were converted to K1 tankers.
Then there was the expensive 'upgrade' to ZD949, which never came back into RAF service despite all the time and effort at Marshall Aerospace.....