He first proposed the famous weapon in a paper published in 1942 before it was deployed a year later. Wiggy - Mary Wallis, then 16 - penned the congratulatory note to her father just three days after the second night of bombing in 1943. Signed 'Wiggy', a family nickname, and dated May 20, it begins: 'Hooray, hooray, hooray!!! Pictured: A bouncing bomb slung in position beneath a Lancaster Bomber flown during the Dambusters raid in 1943. Barnes, hailed as a war hero for his efforts towards the bouncing bomb, died in 1979.

Source: Daily Mail November 03, 2020 12:49 UTC