First World War: Anti-Aircraft Sites
The threat of attack from the air and the best ways in which to counter it was discussed as early as 1909. Some of the earliest defences were put in place to defend the ammunition depot at Chattenden, Kent, and adjacent to it at Lodge Hill, the country’s first permanent anti-aircraft emplacements were built. The site is listed.
One of the responses to the German Zeppelin and Gotha bomber raids was the London Air Defence Area established on 31 July 1917, with its Control centre in Horse Guards. This was the world’s first integrated air defence system of reporting, using tethered balloons, sound locators, searchlights, gun sites and aircraft patrol lines.
By November 1918, this comprised 286 guns, 387 searchlights and eight Home Defence squadrons, in all about 200 fighters, including those stationed at Stow Maries. The new technology of wireless communication also assisted in directing fighters towards their quarries. In total 10 airships and 22 aircraft were brought down by the air defences.
The capital was the most heavily attacked target and elaborately defended area, but many other coastal and northern industrial towns were also attacked, and defences were put in place as well as around key military sites.
Along the east coast experiments were undertaken to develop an early warning system using concrete ‘sound mirrors’. These still survive at Redcar, Kilnsea, Boulby, and Namey Hill, Sunderland. These giant concave ‘dishes’ were used to listen for approaching enemy aircraft by someone literally using a stethoscope to hear the sound of incoming enemy aircraft. They are all listed.