A KLM Royal Dutch Airlines flight declared a mid-air emergency and landed some 478 miles north from where it was scheduled to arrive. The flight diverted to Paris during its journey from Amsterdam to Marseille on Friday morning after it triggered a Squawk 7700, the international aviation code for a general emergency – according to Air Live.  Issuing this signal allowed air traffic controllers to prioritise the plane for immediately landing, with flight maps on Flight Radar 24 showing it rapidly declining from cruising altitude before it reached Paris.  While the aircraft was due to land in Marseille at around 11.35am local time (10.35am GMT), it ended up touching down in the French capital at 11am local time.  Squawk 7700 alerts controllers to immediate distress – such as engine failure, fire, or medical issues – granting the flight priority handling, airspace clearance, and emergency services standby.  While it implies a possibly serious situation, it does not always indicate imminent danger. It’s often used to ensure the crew has maximum support to handle a developing issue …