At end of the 1944 flashback the bomb is dropped from an American B-17 Flying Fortress at night. In 1944-5 B-17s were used as daylight heavy bombers by the American 8th and 15th Air Forces. The type was not used for night bombing.
Germany has its own specialists in rendering leftover World War II munitions safe, known as Kampfmittelbeseitigungsdienst or KMBD.
When Desi shines the light under the beam to check on Helen's legs, you can clearly see that the beam is about 4 " above her ankles.
Despite the title, no windmill appears or is mentioned.
Although the mission is supposed to be set in the German city of Karlsruhe, the aerial shots are featuring Heidelberg.