433 Squadron (RCAF) 6 Group Skipton-on-Swale

WINDOW falls behind the bomber stream

The image at left shows "Window" falling behind the bomber stream. 'The Canadians at War, 1939-1945' volume 2 , Reader's Digest, 1969, page 378, describes the development of 'Window' as follows:

The German system of radar stations, Flak batteries, searchlights, and night fighter stations was producing heavy casualties amongst the allies. Since 1942, British scientists had tested little strips of aluminum foil, 12 inches long, 0.75 inches wide and 2000 per bundle, held together by an elastic band. Released from an aircraft, the bundles broke up in the bomber stream to create bomber sized blips on radar screens. By releasing one bundle per minute from each aircraft in a concentrated bomber stream, it was possible to saturate a screen with blips and make radar directed interceptions very difficult. JB note - not clear which crew member had the job of releasing the Window, one bundle per minute.

On July 15, 1943, the use of Window was approved by the British Cabinet.