Barrage balloons were designed to prevent low-altitude German air attacks against British factories and other strategic targets. Most of these large, hydrogen-filled, football-shaped balloons were connected to wagons by thick steel cables, which could damage any aircraft that hit them. Camouflage and clouds helped prevent enemy pilots from seeing the barrage balloons.
Mobility was crucial in order to form barriers of barrage balloons. Balloon crews, consisting of members of the Women's Auxiliary Air Force and the RAF Balloon Command, moved barrage balloons as needed and operated winches on the wagons to lower and raise the balloons to designated heights. Some barrage balloons actually reached an altitude of 5,000 feet. Not only did they help prevent German pilots from flying at low altitudes, they also increased the vulnerability of enemy aircraft to antiaircraft weapons, which could be concentrated to fire above their altitudes. During the Blitz, balloon crews devoted night duty to keeping barrage balloons at effective defensive heights and positions. Some 66 German aircraft were lost to collisions with barrage balloon cables.
Smaller barrage balloons were also used to protect shipping, and they floated above Allied ships approaching Normandy for the D day landings. In addition to countering airplanes, barrage balloons were used to protect against attacks by V-1 buzz bombs. In 1944, operators placed a circle of 1,750 barrage balloons in south London, and the balloon cables stopped an estimated 231 V-1s.
The United States employed barrage balloons to help protect vulnerable sites on the U.S. West Coast and the Panama Canal. The Allies also used them in North Africa and in other locations in the Mediterranean. The Germans raised barrage balloons over strategic sites in the Reich. Italy and Japan also employed barrage balloons during the war.
A number of the barrage balloons were destroyed by enemy fire or by lightning strikes, and wind and storms often caused balloon damage. Arthur Vestry, a Scottish physicist, devised ways make the balloons lightning-proof, and the Germans sought to develop methods to cut barrage cables without ruining aircraft. Elizabeth D. Schafer
Delderfield, R. F. "A Study in Passive Defence." Royal Air Force Quarterly 16, no. 3 (December 1944–September 1945): 167.; Gossage, Leslie. "Balloon Command." Flying and Popular Aviation 31, no. 3 (September 1942): 97–100.; Robinson, G. N. Barrage Balloons. Maxwell Air Force Base, AL: U.S. Air Force Historical Research Center, 1941.; Turley, R. E. "Barrage Balloons." Coast Artillery Journal 85, no. 1 (January-February 1942): 21–22.
Elizabeth D. Schafer