US government reportedly investigating the FAA's approval process of Boeing 737 Max planes

Getty Images: Boeing 737 Max prepares to take off.

The US Department of Transportation is investigating the Federal Aviation Administration’s approval process for the Boeing 737 Max aircrafts, which were involved in two recent fatal crashes that killed a combined 346 people, The Wall Street Journal reported Sunday.

The department’s probe was launched after a new Boeing 737 Max 8 aircraft flown by Indonesian carrier Lion Air crashed into the Java Sea in October last year, sources familiar with inquiry told the Journal. All 189 people on board were killed in the crash.

According to the report, a grand jury in Washington D.C. issued a broad subpoena to at least one person involved in the development of the 737 Max aircraft. The subpoena was issued just one day after a second crash involving the same model aircraft, flown by Ethiopian Airlines, went down shortly after take off from Addis Ababa, killing all 157 people on board. It is not clear if the two investigations are related, though similarities between the crashes have been noted.

The US’s air-safety agency initially resisted moves by its international peers to ground the 737 MAX after the second crash. 50 countries, including Canada, New Zealand, China, Singapore, Malaysia, France, Ireland, the United Kingdom, and the European Union have since pulled the planes for investigation. President Donald Trump finally issued an order to ground all Boeing 737 Max aircrafts on Wednesday.

According to the Journal, the Department of Transportation is looking into the aircraft’s flight safety system which may have played a role in both crashes. Business Insider transportation correspondent Benjamin Zhang explained that the the MCAS, the Maneuvering Characteristics Augmentation System, is being scrutinised by authorities as they continue their investigation.

“To fit the Max’s larger, more fuel-efficient engines, Boeing had to redesign the way it mounts engines on the 737. This change disrupted the plane’s center of gravity and caused the Max to have a tendency to tip its nose upward during flight, increasing the likelihood of a stall,” Zhang said.

“MCAS is designed to automatically counteract that tendency and point the nose of the plane downward.”

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