Pilot ACE Dead
The scaled-down realization of Turing's ACE design — fastest machine in the world at debut (1 MHz). Turing left NPL before it ran; his architecture ran without him.
Turing designed the Automatic Computing Engine at NPL in 1945–46 — detailed enough to be a working specification, with a stack and subroutines years ahead of practice. Bureaucracy delayed it; Turing left for Manchester in 1948, disillusioned.
The Pilot Model ACE finally ran May 10, 1950 — at 1 MHz the fastest computer in the world for a while. It ran until 1956 and is preserved at the Science Museum, London.