Joanna Chorley

We first met Joanna in 2014 when we invited her along to the 70th anniversary celebrations of Colossus tackling its first Lorenz message. Always very modest of her role in operating Colossus, she had great recall of her days on Bletchley Park and on the eve of the 70th celebrations unexpectedly produced a photograph, taken sometime in 1945, showing the Wren’s Colossus C-Watch.

That photograph was to stir the memories of many surviving Wrens and was instrumental in a much-admired feature on BBC 1’s The One Show. Subsequently, Joanna was to be featured in Tessa Dunlop’s The Bletchley Girls to tell parts of her story. She handled the media with skill and grace and was a natural in front of the camera, but she never sought the limelight for herself. “I was born in a time when girls didn’t blab about everything,” Joanna told Tessa Dunlop.


Since Joanna’s father, Group Captain Stradling, was a military man, she was well aware of the need to keep military secrets. She expected to do ‘light electrical work’ when she was sent to Woburn and Bletchley Park and became fascinated by the machine she came to operate. She met Tommy Flowers, the creator of Colossus, and said she always enjoyed asking questions and finding out about the magnificent machine from the engineers.

Joanna, who lived quite close to Bletchley Park in her later years, was a regular visitor to The National Museum of Computing. Everyone enjoyed hearing her stories, not least the one about the celebrations when the Wrens heard about the end of the war (before most others!). A group of Wrens, Joanna amongst them, were severely told off for decorating the tree that once stood in the Block H car park in toilet roll. The toilet roll had to removed in double-quick time and silence maintained!

Joanna Chorley with the book in which she features

Joanna Chorley with the book in which she features

On her regular visits back to Block H and The National Museum of Computing, Joanna’s fun-loving nature shone through. Once ]she returned to fly a remote-controlled drone](/news/news-releases/colossus-veteran-controls-drone) with quite some skill; on another occasion, she came to celebrate the launch of the Colossus celebratory stamp by Royal Mail.

Andrew Herbert, chairman of TNMOC, said, “It’s so sad to lose another veteran. Theirs was an amazing generation to whom we are all grateful for the freedoms we enjoy today.”

We are indebted to Joanna Chorley for her help and support in telling the story of Colossus and the breaking of Lorenz and send our best wishes to her family, especially her daughter Alison Marshall, who was unfailing helpful in bringing Joanna to the museum and joining in the celebrations.