The "RB-66C" was a specialized electronic reconnaissance and electronic countermeasures (ECM) aircraft; according to Gunston and Gilchrist, it was the first aircraft designed from the onset for electronic intelligence (ELINT) missions. It was operated by an expanded crew of seven, which included the additional electronics warfare specialists. A total of 36 of these aircraft were constructed; the additional crew members were housed in the space that was used to accommodate the camera/bomb bay of other variants, these aircraft were outfitted with distinctive wingtip pods that accommodated various receiver antennas, which were also present upon a belly-mounted blister. Several RB-66Cs were operated in the vicinity of Cuba during the Cuban Missile Crisis, they would also be deployed over Vietnam. During 1966, these planes were re-designated as "EB-66C".