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Concept
Ballon de barrage
Résumé
A barrage balloon is a type of airborne barrage, a large uncrewed tethered balloon used to defend ground targets against aircraft attack, by raising aloft steel cables which pose to hostile aircraft a severe risk of collision, making the attacker's approach difficult and hazardous. Early barrage balloons were often spherical. The kite balloon, having a shape and cable bridling which stabilises the balloon and reduces drag, could be operated at higher wind speeds than could a spherical balloon. Some examples carried small explosive charges that would be pulled up against the aircraft to ensure its destruction. Barrage balloons are not practical against high-altitude aircraft. The long cable required for a high-altitude balloon would be too heavy.
France, Germany, Italy and the United Kingdom used barrage balloons in the First World War. While the French and German forces developed kite balloons, early British barrage balloons were spherical.
Sometimes, especially around London, several balloons were used to lift a length of "barrage net": a steel cable was strung between the balloons and more cables hung from it. These nets could be raised to an altitude comparable to the operational ceiling () of the bombers of that time period. By 1918 the barrage balloon defences around London stretched for , and captured German pilots expressed great fear of them.
In 1938 the British Balloon Command was established to protect cities and key targets such as industrial areas, ports and harbours. Balloons were intended to defend against dive bombers flying at heights up to , forcing them to fly higher and into the range of concentrated anti-aircraft fire: anti-aircraft guns could not traverse fast enough to attack aircraft flying at low altitude and high speed. By the middle of 1940 there were 1,400 balloons, a third of them over the London area.
While dive-bombing was a devastatingly effective tactic against undefended targets, such as Guernica and Rotterdam, dive-bombers were very vulnerable to attack by fighter aircraft when pulling up after having completed a bombing dive.
Source officielle
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