British Defences

"It was a process of evolution, of trial and error, and even if we achieved success with new devices, new instruments or new methods, the public should never be told that raiders were not going to get through at all times."

Captain Balfour

Under-Secretary of State for Air

9th October 1940

After the Fall of France, the build up of British defences accelerated, as the prospect of a German invasion loomed. Coastlines were prepared with pillbox structures, anti-tank obstacles and barbed wire, in case of an amphibious assault. A barrage balloon site in Liverpool. Balloon Command grew from 624 balloons in 1939 to 1466 in service. 450 balloons were used to defend London alone. The balloons were set at 5,000 feet, forcing the enemy to climb, affecting their bombing accuracy and putting them in range of the anti-aircraft guns. Searchlights stationed at the gun batteries had the same effect.

The British Army had lost much of its heavy equipment during the evacuation of Dunkirk; in the summer of 1940 even ammunition was in short supply. The Army would have to do the bulk of the fighting if an invasion took place but they were supplemented by members of the Local Defence Volunteers (later the Home Guard).

The Royal Navy remained a formidable An Army anti-aircraft gun in action during raid. The Bofors 40mm gun was the standard light gun while heavier guns used were mobile 3.7inch and the fixed 4.5inch. To boost morale during an air raid, elder 3inch guns set on lorries were sent through towns and encouraged to fire whenever passing a shelter. force even though it had suffered some losses during the early summer. If a German invasion set sail significant numbers of Royal Navy ships would have moved into the Channel and have attempted to inflict considerable losses on any enemy invasion forces.

The Royal Air Force had both Fighter and Bomber Command as their major offensive arms but as a defence RAF Balloon Command placed barrage balloons around potential target areas.

The Army's Anti-Aircraft Command batteries worked with light and heavy anti-aircraft guns in co-operation with searchlight units. They were stationed to defend airfields, towns and factories.

'K' and 'Q' sites were decoy airfields set up to divert enemy bombing from their actual target. Starfish sites were also used in the same way to protect towns and cities.

ATS officers operate a searchlight. ATS officers operate a searchlight

All searchlights were equipped with a light machine gun and accompanied by a sound locator, which indicated an initial bearing on the enemy aircraft.

This barricade not only illustrates the improvised nature of many of the British defences but also that significant travel restrictions were placed upon civilians - even if they could obtain sufficient petrol. Barricade - British defences

In the summer of 1940 some of the most extraordinary defence schemes were put into place. Oil defence was such proposal. As the invasion neared the shore oil would be pumped out onto the sea surface and then set alight. Oil defence scheme

A number of bodies of badly burned German servicemen washed up on the English east coast created a myth that this system had been used operationally.

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 Bernard Rice

Bernard Rice

First World War Pilot
3 Pilots 1 War
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