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 put up by the ARP. (PROSE: The Time Traveller's Almanac) Barrage balloons were used in the London 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. The balloon drifted into the open and Rose narrowly avoided the Luftwaffe aeroplanes flying around her. She was saved from plummeting to her death by Jack Harkness, who used a tractor beam to stop her fall. (TV: The Empty Child)

On the Inferno Earth barrage balloons were used to protect strategic sites in major cities from attack by hijacked aircraft. (PROSE: I, Alastair)

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