Flying in the Coffin Corner–Air France Flight 447

When Air France Flight 447 disappeared in June 2009, it was in the middle of the tropical Atlantic and had likely entered a mesoscale convective complex , a system of strong thunderstorms thought to have been at least four storms deep along 447’s flight path. Flight 447 was also flying at a cruise altitude of 35,000 feet, an altitude where the relationship between an aircraft’s stall speed and the speed of sound has gained the name “the coffin corner”

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Flying in the Coffin Corner–Air France Flight 447