Investigation Summary
Flight 553 was on a multi-leg journey from New York to Chicago, with scheduled stops in Harrisburg, Pennsylvania; Pittsburgh, Pennsylvania; and Dayton, Ohio. As the DC-9 descended through 4,500 feet at 323 knots, it was operating in a high-speed regime below 10,000 feet that was legal at the time but significantly reduced the time available for visual scanning. The Beechcraft Baron, N6127V, was traveling southbound from Detroit to Springfield and was not in contact with Air Traffic Control. The Dayton radar controller observed a slow-moving target and warned the TWA crew, who acknowledged the advisory 14 seconds before impact. Cockpit Voice Recorder data indicated the crew never actually sighted the Beechcraft. The NTSB investigation highlighted that the DC-9 was the overtaking aircraft, placing the primary responsibility for avoidance on its crew, yet also noted that the ATC system of the era was not equipped to safely manage the mixture of high-speed controlled jet traffic and slow-moving uncontrolled VFR traffic in terminal areas.
Final Conclusions
The National Transportation Safety Board determined the probable cause was the failure of the DC-9 crew to see and avoid the Beechcraft. Contributing factors included physiological and environmental conditions, the excessive speed of the DC-9 which reduced visual detection capabilities, and an air traffic control system that was not designed to provide separation between controlled and uncontrolled traffic in such environments.
Video Analysis
Too Fast To Catch | 1967 Dayton, Ohio Mid Air Collision — A detailed look at the mid-air collision between TWA Flight 553 and a Beechcraft Baron near Urbana, Ohio, and the resulting changes to aviation speed limits.
If playback is blocked, the owner has disabled embedding — use the link above.
Airframe & Maintenance
Trans World Airlines TW553 — Douglas DC-9-15 · N1063T
Systems & Failure Modes
See and Avoid
The primary method of collision avoidance in VFR conditions, requiring pilots to visually scan for other aircraft. The NTSB found this inadequate for high-speed jet descents.
Dayton Radar Approach
The ATC facility providing advisory services to TWA 553; however, the Beechcraft was not under its control or in radio contact.
Interesting Facts
- 01The DC-9 was traveling at 323 knots (372 mph) at the time of the collision.
- 02Visual Flight Rules (VFR) were in effect with visibility of six to seven miles, exceeding the three-mile requirement.
- 03The Beechcraft Baron disintegrated in flight immediately upon impact.
- 04The collision occurred approximately 25 nautical miles northeast of Dayton Municipal Airport.
- 05The radar controller did not see the Beechcraft on his scope until 22 seconds before the crash.
Safety Actions & Advisories
FAR Part 91.85 Amendment
Following the accident, the FAA prohibited all aircraft from exceeding 250 knots IAS when operating below 10,000 feet MSL.
Terminal Control Areas (TCA)
The accident influenced the FAA's decision to create TCAs (now Class B airspace) to provide positive control and separation around the nation's busiest airports.