Aircraft with bright white blinking light. Velocity 200- 500 mph 0315 hrsAt 03:15 aprox. I saw a white flashing light traveling at 200 to 500 mph at an altitutude of 2,000 to 8,000 ft. break the tree line and do an 180 degree turn. However I lost sight of object as it traveled back into tree line. Object was only visable by flashing light. The air craft blinked five times in about 2.5 seconds estimated velocity at 200 to 500mph. Most aircraft cant make a 180 turn in 2.5 seconds.At first I thought object was a fixed wing aircraft beacause of the blinking light, however, when object reversed at 180 degrees I realized that the object was not a fixed wing machine. I have spent a year at an Army air base in South Korea and I am well aware of the manuverability of most NATO and Comercial aircraft. I may be mistaken but I don't think so.Note, I could not see the body of the craft only the blinking light. The distance from craft was at least two or three miles.