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Responding to increasing Soviet pressure on western Berlin, U.S. and British planes airlift a record amount of supplies into sections of the city under American and British control. The massive resupply effort, carried out in weather so bad that some pilots referred to it as “Black Friday,” signaled that the British and Americans would not give in to the Soviet blockade of western Berlin.
Berlin, like all of Germany, was divided into zones of occupation following World War II. The Russians, Americans, and British all received a zone, with the thought being that the occupation would be only temporary and that Germany would eventually be reunited. By 1948, however, Cold War animosities between the Soviets and the Americans and British had increased to such a degree that it became obvious that German reunification was unlikely. In an effort to push the British and Americans out of their zones of occupation in western Berlin, the Soviets began to interfere with road and rail traffic into those parts of the city in April 1948. (Though divided into zones of occupation, the city of Berlin was geographically located entirely within the Russian occupation area in Germany.)
In June 1948, the Russians halted all ground and water travel into western Berlin. The Americans and British responded with a massive airlift to supply the people in their Berlin zones of occupation with food, medicine, and other necessities. It was a daunting logistical effort, and meant nearly round-the-clock flights in and out of western Berlin. August 13, 1948, was a particularly nasty day, with terrible weather compounding the crowded airspace and exhaustion of the pilots and crews. Nevertheless, over 700 British and American planes landed in western Berlin, bringing in nearly 5,000 tons of supplies.