original_query: What was the Mechelen incident of 10 January 1940?
query: What was the Mechelen incident of 10 January 1940?
answer: On January 10, 1940, a German plane carrying Major Helmuth Reinberger, who possessed the plans for Fall Gelb (the German attack on the Low Countries), crash-landed in Belgium.  Reinberger's attempts to destroy the documents were unsuccessful, leading to a major crisis and impacting German military strategy.