Balloon with a view

摘要

The barrage balloon has been utilised in defence for decades. Large, tethered balloons were used during World War Ⅱ by the Allies to protect vital strategic areas from low-level aircraft attack, and later deployed in nuclear tests to allow experiments at higher altitudes, perhaps most notably in the Operation Plumbbob tests in Nevada in 1957. Today, however, a new generation of hi-tech, helium-filled moored craft are on the rise, as more and more forces turn to aerostats capable of lifting large payloads thousands of feet into the air to provide effective downward-looking surveillance.