|Oct. 25, 2017; Pacific Northwest
4:30 p.m. PST. Radar tracking of primary target crossing N. California at very high speed and 37,000 feet. Object had also been observed from an airliner which reported the very large, white, unidentified "aircraft" had been southbound then abruptly made U-turn to the north and then became invisible to radar. Three aircrews were able to keep a visual on it for almost 45 minutes as it proceeded into Oregon and Washington airspace at over 450 kts. but unable to identify it. ARTs tried to contact the object which was not putting out a transponder code and apparently NORAD scrambled F-15's very early in the incident.