Fifty years ago, three IBM System 370 mainframe computers were used in the pioneering scheduling system run by the UK's national rail operator, British Rail. Named the Total Operations Processing System (Tops) when it went into operation on 27 October 1975, it revolutionized the control of all rail freight operations across the UK online and online. in real time.
He used British Rail's own line. telephone network and along with a pair of IBM System 370/168s and a System 370/158 mainframe, Ventek minicomputers with built-in punch card machines were installed at each cargo terminal.
An article published in the October 30, 1973 issue of Computer Weekly described the system as: “One of the most extensive and comprehensive freight management systems in the world.”
Commenting on the 50th anniversary, Jonathan Eilen, a Tops specialist from the University of Manchester, said: “Tops covered the whole of Britain, every freight wagon and locomotive, every train movement and every load, all controlled by a central computer system at Marylebone in London. The control's headquarters have been described as 'space age' for its time.”
Marylebone housed 32 IBM 3330/33301 control data drives, providing a whopping 3.2MB of storage.
A Computer Weekly article reported that Tops had divided the country into 152 Tops Responsibility Areas (TRAs), each equipped with a Ventek 9200 minicomputer system. Describing the system's operation, the Computer Weekly article noted: “The basis for Tops in field is a punch card, one card per car. As traffic moves from one TRA to another, new cards are created showing the changed status. Receiving officer at a regional freight center (AFC), checks maps with cars and enters this information into the system to update the database.”
As Eileen noted in The Convergence of Computing and Telecommunications: The Cold War and Coal Trains In a paper he co-authored in 2024, the network used by British Rail was state-of-the-art at the time, using coaxial cables for the main trunk lines with analogue transmission at 4 MHz (equivalent to 960 telephone channels). Local communication lines were carried out using 12-channel frequency division multiplexing systems over symmetrical copper cable pairs. They provided high quality voice communications over 4 kHz channels to every major station, office complex and freight station in the country.
But it also spread abroad. Computer Weekly reported that Ventek minicomputers were also deployed in France at Dunkirk, and a telex line existed in Zeebrugge, Belgium. Data from the freight centers was fed into the Marylebone computer room via data network who walked 400 km.
“Today we take computer control of business operations for granted. But fifty years ago it was a revolution to know what was happening in a business in real time, especially a system that tracked up to 3,000 freight trains daily,” Eilen said.
Tops highlighted the real demand for the carriages, which meant that many were surplus and sold for scrap, reducing maintenance costs and helping to pay for the entire system.
Bob Gwynne, a railway expert, said: “This had one major unintended consequence: one scrapyard in South Wales focused on the quick and easy disposal of carriages. Complex steam locomotives were shelved for later. This respite resulted in 213 steam locomotives being acquired for conservation, about two-thirds of the total number of steam locomotives surviving today.”
“So the unintended effect of Tops was the birth of heritage railways as a national tourism product rather than a handful of pre-1975 destinations.”
Thank you very much National Museum of Computing (TNMOC) for providing scans of the original Computer Weekly article. The complete Computer Weekly archive for September 1966 is housed at TNMOC.
