I'm a truck driver for a production company in Chicago. On the afternoon of December 11, 2015, I was traveling east on Interstate 40 in the center lane just west of exit 145 in Oklahoma City. At approximately 2:15 pm CST. I witnessed a commercial airliner taking off and traveling west. It quickly made a sharp 90 degree turn and headed south across the interstate. During its accent and travel west I noticed a circular shaped Black object flying directly above the main cabin. As the airliner made its 90 degree turn the circular object stayed directly above the airliner. The airliner was now traveling south and had leveled out at about 3000 feet. During the entire time I witnessed the event the object was able to stay directly above the commercial jet. Passing behind the object I was able to determine that the object was not connected to the airliner in any way. The object was a perfect circle, dark black in color. I would estimate the object was 100 to 150 feet in diameter. The object was a perfect circle. The object did not have any markings or visible lines. It was about 200 to 300 yards above the jet airliner the entire time. It continued south as I continued east on Interstate 40. I feel this object was a craft of some kind. I'm very familiar with airplanes landing and taking off, as I'm a resident near ohare airport in Chicago. Frank Losurdo