Air raid sirens and propeller aircraft are closely associated with the Second World War, when sirens warned civilians of incoming bombing raids and propeller-driven planes dominated the skies. Recordings combining the two have become a familiar shorthand for wartime danger in documentaries, films and online video, where a few seconds instantly signal threat without any explanation. Creators continue to use this longer flyover version for historical edits, war-themed games and dramatic storytelling because the slow build from warning to overhead roar feels authentic and immediately recognisable.