Yes: http://www.ivorcatt.com/47c.htm (It's also available behind the IEEE pay-wall.) That issue of the Annals (5/3) has a couple of articles about Colossus; the Coombs one on the design is available here: http://www.ivorcatt.com/47d.htm but doesn't have much on the reliability issues; the Chandler one on maintenance has more, but alas is only available behind the paywall: https://www.computer.org/csdl/mags/an/1983/03/man1983030260-abs.html Brian Randell did a couple of Colossus articles (in "History of Computing in the 20th Century" and "Origin of Digital Computers") for which he interviewed Flowers and others, there may be details there too. Noel