The BA Tri-Stars and the Gulf- Air ones did have PVD's and they worked very well as did the whole auto-pilot system. Wonderful machine.
There was a home video taken at the time of Cat3 qualification, I think at Edwards, that shows a TriStar doing an auto-land with NOBODY in the seats. I heard that the rush for the seats once it touched down would have won the Olympics.
I was on them for nine years and they were the best of my career.