The path of the 727 was along the airway Victor 23*. According to the FBI, the jump occurred over Ariel, Washington. According to Bobby, the jump occurred about 9 minutes after passing over the Columbia River. The money was found at the edge of the Columbia on Tina Bar (N 45° 43.048 W 122° 45.576) . 

A Victor Airway is an eight-mile-wide highway in the sky. 

#1 = Ariel, Washington, the site where the FBI thinks D. B. Cooper Jumped

#2 = Tina Bar where $5800 of the Cooper money was found                           

#3 = Where we were told the jump actually occurred.   

* A Victor Airway is a "highway in the sky" for aircraft. It is an eight mile wide path that is used based on altitude, direction, and speed. This would have been the only safe route to fly that night based on the altitude, destination and speed requested by the skyjacker.