1955 Altensteig mid-air collision
The Altensteig mid-air collision occurred on 11 August 1955 when two United States Air Force Fairchild C-119G Flying Boxcars collided and crashed three miles from Altensteig in West Germany. The aircraft were part of a formation of nine C-119s flying a training mission from Stuttgart-Echterdingen airfield, West Germany with troops from the United States Seventh Army.
Source: Wikipedia — 1955 Altensteig mid-air collision (CC BY-SA 4.0)