Barrage balloon

Barrage balloons were large balloons tethered to the ground with cables. These cables were designed to damage any planes attempting a low flying attack. They were employed in the United Kingdom during World War II to defend against bombing by the Luftwaffe.

Rose Tyler tried to use the cable of a barrage balloon to reach a small child who was stood on a rooftop. However, the balloon drifted out into the open and Rose narrowly avoided the Luftwaffe aeroplanes flying around her. She was saved from plummeting by Jack Harkness when he used a tractor beam to stop her fall. (DW: The Empty Child)