The procurement and maintenance of the Corona satellites were managed by the Central Intelligence Agency (CIA), which used cover arrangements lasting from April 1958 to 1969 to get access to the Palo Alto plant of the Hiller Helicopter Corporation for the production. At this facility, the rocket's second stage Agena, the cameras, film cassettes, and re-entry capsule were assembled and tested before shipment to Vandenberg Air Force Base. In 1969, assembly duties were relocated to the Lockheed facilities in Sunnyvale, California. (The NRO was worried that, as Corona was phased out, skilled technicians worried about their jobs would quit the program — leaving Corona without staff. The move to Sunnyvale ensured that enough skilled staff would be available.)