Same problem at Brawdy in the summer of '76. Roasting hot day - but inside one's Hunter it was raining so hard it was impossible to see out - or to read most of the instruments. Much frantic wiping with aircrew glove....I even considered slowing down, sticking down full flap and opening the hood.
Wretched Hawkers - did they learn nothing about cockpit conditioning from their failures in earlier years when it came to the bona jet?