Trans World Airlines / Private Flight 553Thursday March 9, 1967
Midair collision. Twenty five killed on the DC-9, one on the Beechcraft. Failure of the DC-9 crew to see and avoid the Beechcraft. The DC-9 was traveling at almost 300 mph at low altitude in airspace occupied by numerous small planes. The contributing factor to the accident was the excessive speed of the DC-9. ATC systems inadequate to separate controlled and uncontrolled traffic. After this accident, the FAA imposed a maximum speed of 250 knots below 10,000 ft. mean sea level.