It was the Lynx that was used for flight control law research, ACT Lynx, ACT for Active Control Technology. I think it was a venture with Westlands of Yeovil.
Farnborough had a Jaguar for flight control law research, which they weighted down the tailplane with lead and some extensions on the leading edges of the wings so as to upset the stability (lead in the tailplane ought to do it). It was a BAe project I think.
The aircraft is still there, on permanent display at one of the entrance gates.