Boeing WC-135 Constant Phoenix

The WC-135 Constant Phoenix is a special-purpose aircraft derived from the Boeing C-135 Stratolifter and used by the United States Air Force to collect samples from the atmosphere in order to detect and identify nuclear explosions; workers call it the weather bird and the international media the sniffer. It was introduced in December 1965 to replace the WB-50 in weather reconnaissance and air sampling, with ten aircraft converted from C-135B transports and placed in service with the 55th Weather Reconnaissance Squadron at McClellan Air Force Base, California. In February 1974 the Air Force ordered that after 1 July 1974 WC-135s be used for atmospheric sampling only. When frontline weather reconnaissance ended in the early 1990s five were retained, and serial 61-2667, upgraded to a WC-135W and given the project name Constant Phoenix, remains in service with the 45th Reconnaissance Squadron at Offutt Air Force Base, Nebraska.