Gatow Air Disaster of 1948

The Viking collided head-on with a Russian Air Force Yakovlev 3 fighter, which was performing aerobatics. The Viking spiraled slowly without control and crashed. The fighter pilot was also killed.

PROBABLE CAUSE: "The collision was caused by the action of the Yak fighter, which was in disregard of the accepted rules of flying and, in particular, of the quadripartite flying rules to which Soviet authorities were parties."

http://www.webcitation.org/5iRFohD7O