On April 23, 1953, while still an active air force officer, he was appointed Deputy Director of the CIA under Allen Dulles. In 1956, along with the CIA's Richard Bissell, he flew to Bonn, to brief the West German Chancellor, Konrad Adenauer, on the ultra-secret U-2 spy plane. Cabell personally negotiated with Chancellor Adenauer for permission to station the U-2 in Wiesbaden and from there to fly over the Soviet Union illegally. It was the U-2 program that allowed CIA chief Allen Dulles to sabotage the peace summit between Khrushchev and Eisenhower.