Investigation Summary
The accident occurred while the DC-3 was flying approximately eight miles to the right of the Amber 7 airway boundary. The USAAF A-26 was returning to Florence Army Air Field after a training mission and was practicing aural nulls, a maneuver involving a shallow left bank of 15 to 20 degrees. This bank restricted the Army pilot's vision to the right, the side from which the DC-3 was approaching. The DC-3 was in a shallow descent of 200 feet per minute. Both pilots observed the other aircraft only seconds before impact, with the DC-3 captain pulling back on the controls and the A-26 pilot pushing forward in a futile attempt to dive under the airliner. The A-26's vertical fin struck the DC-3's left wing, tearing the left engine from its mounts. The detached engine and its rotating propeller then struck the DC-3's fuselage, causing fatal injuries to a passenger. The DC-3's right propeller subsequently severed the A-26's fuselage, causing the military aircraft to crash and burn.
Final Conclusions
The Civil Aeronautics Board determined the probable cause was the failure of each pilot to see the other aircraft in time to avoid a collision. Contributing factors included the DC-3 pilot's deviation from the designated airway in the vicinity of an active military airbase and a lack of vigilance. Additionally, the Army pilot continued a maneuver that restricted his vision in an area not specifically reserved for such training exercises.
Video Analysis
No video analysis linked for this case file yet.
Systems & Failure Modes
Aural Null Training
A navigation training maneuver where the pilot listens for the 'null' or silent spot in a radio signal to determine direction, often requiring specific aircraft attitudes that can limit external visibility.
Amber 7 Airway
The designated civil airway the DC-3 was supposed to follow; the aircraft was found to be 8 miles outside this corridor at the time of impact.
Interesting Facts
- 01The DC-3 was flying approximately 8 miles off the designated airway at the time of the collision.
- 02The A-26 was in a 15 to 20 degree left bank for over a minute, which created a blind spot in the direction of the DC-3.
- 03The DC-3's left engine was completely torn from the wing during the sequence of impacts.
- 04The only fatality on the DC-3 was a two-year-old boy who suffered head injuries when the engine hit the fuselage; his mother, Mrs. Williams, was seriously injured.
- 05The collision occurred at an altitude of approximately 3,100 feet.
Safety Actions & Advisories
Vigilance in Military Training Areas
The report emphasized the need for increased vigilance by civil pilots when operating near active military bases and for military pilots to avoid vision-restricting maneuvers in non-restricted airspace.