During the Cold War, U.S. pilot, Francis Gary Powers was traded by the Russians back to the United States in exchange for one of their spies.
The United States was able to get almost perfect photos of the Soviet Union during the 1950s and 1960s. It was impressive since they did not have satellite imagery or any of the high-end equipment the military employs now.
But, in order to get the photos, the Air Force had to physically fly over the area and snap a photo. Not the safest way to gather intel, especially when flying over hostile countries.
The pilots did have U-2 spy planes flying with them as a level of protection. They flew at a high altitude so that surface-to-air missiles would not shoot them down.
Shooting Down A Spy Plane
The U-2's pilot was Francis Gary Powers. The Soviet Union fired a long-range surface-to-air missile hitting the spy plane. Powers was supposed to start the self-destruct sequence and take a cyanide pill from the CIA.
However, he decided to bail instead, and the KGB captured him. The U-2 crashed into bits, but pieces were placed up for display. Powers was put on trial and sentenced to three years in a Soviet prison cell, plus seven years of hard labor.
But, Powers only spent a year in prison. He and an American student were traded on February 10, 1962, for a spy the Americans had captured, Rudolf Abel.
The two countries traded their prisoners in Berlin by walking across the Glienicke Bridge.