My Grandfather (Harry James Butler) worked for many years for the Dunlop Aircraft Division but in the late 1940’s was tasked with adapting the early aircraft disc brakes for use in cars. As the Chief Design Engineer and overcoming many problems,
Harry devised the first disc brakes to be used in cars. His ingenuity resulted in their demonstration and ultimate triumph in the Le Mans 24 hour races in the 1950’s Jaguar D type. Their superiority in braking performance over drum brakes meant that the D types could decelerate much later when approaching corners and this was attributed to their winning streak.
I have many of the original detailed technical drawings, specifications and patents which may be of interest to your forum members. His design, first used on the D type and put into production on the XK 150, was the predecessor of the disc brakes we all use today.
In addition, I have some photographs, launch brochure and pre-launch publicity information which I would be happy to share if anyone is interested in! This includes an intriguing Nazi alternative to the use of as asbestos for brake pads- which I believe Dunlop didn’t follow up on.