In the past six months, two airplanes have fallen out of the air and crashed shortly after takeoff. Both flights were operating the same plane: the Boeing 737 Max 8.

In October, Lion Air Flight 610 crashed in Indonesia, killing 189 people. And last month, Ethiopian Airlines Flight 302 crashed in Bishoftu, Ethiopia, killing 157 people.

At first, the story Boeing tried to tell was that it was a software problem; the automated stall-prevention system was malfunctioning, the company said. And the accident reports seem to support this statement.

But there’s a much deeper and scandal-ridden story about how this plane got to market, and it starts with Boeing’s fierce rivalry with Airbus — and their race to put a new engine in their planes.

The video above shows how those business problems led to technical ones — and, eventually, two terrible tragedies.

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