The OC-135B Open Skies United States Air Force observation aircraft supports the Treaty on Open Skies. The aircraft a modified WC-135B flies unarmed observation flights over participating parties of the treaty. Three OC-135B aircraft were modified by the Aeronautical Systems Center's 4950th Test Wing at Wright-Patterson Air Force Base in Ohio. The first operationally capable OC-135B was assigned to the 24th Reconnaissance Squadron at Offutt AFB in October 1993.
Made by BoeingBoeing Military Airplanes Division.
It is the successor of the Boeing C-135 Stratolifter ,
Boeing OC-135B Open Skies is the predecessor of the Boeing WC-135 Constant Phoenix.