The first Lockheed Skunk Works contract with the CIA wasn't the U-2 spyplane, but a spyplane adaptation of the Lockheed P2V Neptune maritime patrol aircraft. Predating the U-2 contract by several months, seven P2V-7 Neptunes were modified by Kelly Johnson's team into RB-69s. The aircraft were equipped with the first operational terrain avoidance radar (built by Texas Instruments), doppler navigation radars, a variety of ECM equipment, and in later years a large General Electric SLAR unit in a housing on the right side of the aft fuselage.
The first missions assigned to the RB-69s were the mapping of the Russian power grid in Eastern Europe. Missions were flown out of Wiesbaden AB in West Germany in 1955-1956. Beginning in 1957, missions were also flown over China from bases in Taiwan, usually with Taiwanese crews and markings.
Source: Lockheed Secret Projects: Inside the Skunk Works by Dennis Jenkins. MBI Publishing, 2001, p29.