04/19/2007. Remarks by Johan Visschedijk: "This is the second prototype T.Mk.2 that flew for the first time on July 14, 1969. Used for trial work from its maiden flight on, it was converted to a T.Mk.4 in 1973 and to a T.Mk.4A in 1983. Lately it has been involved as a test bed in the Vectored thrust Aircraft Active Control (VAAC) program. It is still in use at QinetiQ."