The Mechelen incident of 10 January 1940, also known as the Mechelen affair, took place 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 crash The incident was caused by an error 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 1940, 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. At that moment, Hoenmanns seems by mistake to have cut off the fuel supply to the plane's engine by moving a lever inside the cockpit. The engine spluttered, then stopped, and Hoenmanns was forced to land in a nearby field at about 11:30 AM. The aircraft was severely damaged. Both wings were broken off when they hit two Canadian poplar trees as he sped between them; the heavy engine tore off the nose section. The plane was damaged beyond repair, but Hoenmanns survived unscathed. Had Hoenmanns been alone in the plane, nothing of great significance would likely have happened, apart from his internment for landing without permission in a neutral country. However, he had a passenger, Major Helmuth Reinberger, who was responsible for organising the 7. Flieger-Division's supply, the formation that was to land paratroopers behind the Belgian