The development was formalized after a key demonstration on February 26, 1935, known as the Daventry Experiment. Watson-Watt and Wilkins successfully reflected radio waves off a Handley Page Heyford bomber, proving aircraft detection was possible. By June 17th that same year, a permanent research station at Orford Ness achieved the first operational tracking. The breakthrough wasn't the weapon they feared, but a defensive 'shield.' The British Treasury funded a five-station system called Chain H