Mechelen Incident

The Mechelen Incident of 10 January 1940, also known as the Mechelen Affair, was an event which occurred in Belgium during the Phoney War in the first stages of World War II. A German aircraft with an officer on board carrying the plans for Fall Gelb (Case Yellow), the German attack on the Low Countries, crash-landed in neutral Belgium near Vucht in the modern-day municipality of Maasmechelen within the Province of Limburg. This prompted an immediate crisis in the Low Countries and amidst the French and British authorities, whom the Belgians notified of their discovery; however the crisis abated relatively quickly once the dates mentioned in the plans passed without incident. It has been argued that the incident led to a major change in the German attack plan, but this hypothesis has also been disputed.

The affair began with a mistake made by the German aviator Major Erich Hoenmanns, the fifty-two-year-old base commander of Loddenheide airfield, near Münster. On the morning of 10 January, he had been flying a Messerschmitt Bf 108 Taifun, an aircraft used for reconnaissance, liaison, and other miscellaneous roles, from Loddenheide to Cologne when he lost his way; extensive low fogbanks obscured his view of the landscape. In response he changed course to the west, hoping to regain his bearings by reaching the River Rhine. However, having already crossed over the frozen and indistinguishable Rhine at the moment he changed direction, he left German territory flying all the way to the River Meuse, the border in this area between Belgium and The Netherlands, and ended up circling Vucht.

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