"Goodbye Blue Sky" is a poignant reflection on the trauma of war, specifically recalling the Blitz. It opens with the innocent observation of a child noticing a plane, which quickly gives way to the terrifying memory of falling bombs and the desperate need for shelter. The song contrasts the hopeful vision of a "brave new world" with the harsh reality of destruction, acknowledging that even after the physical flames are gone, the emotional pain endures. Featured on Pink Floyd's 1979 album The Wall, it plays like a somber lullaby carrying the weight of past horrors.