COBRA31
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. Its mission is to collect samples from the atmosphere for the purpose of detecting and identifying nuclear explosions. It is also informally referred to as the "weather bird" or "the sniffer" by workers on the program and international media respectively.
https://en.wikipedia.org/wiki/Boeing_WC-135_Constant_Phoenix
https://radmon.org/index.php