Boeing comes under scrutiny from American and international regulators, as well as the US Congress, which is investigating complaints from American pilots about the MCAS, and the close ties between the FAA and the company

Washington (AFP) - From its first flight to fatal crashes and being cleared by US regulators on Wednesday to return to the skies, below are key dates related to the Boeing 737 MAX.

- Two deadly disasters -

The Boeing 737 MAX, a narrow body aircraft that can transport up to 230 passengers, is certified to fly on March 8, 2017 by the US Federal Aviation Agency (FAA). It is put into service in May.

On October 29, 2018, a 737 MAX from budget airline Lion Air crashes off the coast of Indonesia, killing 189 passengers and crew members.

Less than five months later, on March 10, 2019, an Ethiopian Airlines 737 MAX, flying to Nairobi, crashes near Addis Ababa, claiming 157 lives.

- Grounded worldwide -

China is the first country to ban the aircraft, on March 11. Regulators worldwide follow suit, but American officials initially say there is “no basis” for grounding.

US President Donald Trump intervenes on March 13 announcing the planes would be grounded “effective immediately.” The FAA issues the official decree shortly after.

- Crash investigations -

Indonesian authorities publish a preliminary report on the Lion Air crash on November 28, 2018 – months before the second disaster – citing inadequate pilot training, and flawed design and certification of the MCAS flight control software.

The MCAS, which lowers the aircraft’s nose if it detects a stall or loss of airspeed, was developed specifically for the 737 MAX, which has heavier engines than its predecessor in the 737 family.

But it relied on a single sensor which made it vulnerable to failure.

On March 17, 2019, Ethiopian Transportation Minister Dagmawit Moges reveals “clear similarities” between the Ethiopian Airlines flight 302 and Lion Air flight 610.

The MCAS anti-stall system was activated automatically in both disasters after receiving erroneous information indicating that the aircraft was stalling. The pilots were not aware of the existence of this software since it was not in the flight manuals.

Boeing comes under scrutiny from American and international regulators, as well as the US Congress, which is investigating complaints from American pilots about the MCAS, and the close ties between the FAA and the company.

- Production stopped -

Boeing is forced to suspend deliveries on March 14, 2019, but the company initially maintains MAX production at 52 planes a month.

Output is later cut to 42 a month for the plane, which represented nearly 40 percent of Boeing sales in 2018.

But on December 17, after the FAA made it clear the MAX would not return to the skies anytime soon, Boeing announces it will halt production of its flagship aircraft in January 2020, for an indefinite period.

- Leadership shakeup -

The company continues to express confidence that the MAX would return to the skies by the end of 2019, as it addresses software modifications and improved pilot training, but is criticized for putting pressure on regulators to rush the plane back into service.

Airlines are forced to push back the expected date for returning their Boeing 737 MAX fleets to service.

A week after announcing the production halt, Boeing on December 23 ousts Dennis Muilenburg, who has been at the helm of Boeing since 2015. The company already stripped him of his title of chairman of the board in October.

Boeing named board Chairman David Calhoun as chief executive and president, saying the company needed to “restore confidence” and “repair relationships with regulators, customers and all other stakeholders.”

- Cleared for return -

In May 2020, Boeing announces that it has gradually restarted production and in June the plane completes its first re-certification flight.

In September, FAA chief Steve Dickson himself takes the plane for a test flight, saying it “responded well” during two hours of flying.

American Airlines says it plans to begin flying the Boeing 737 MAX in December between Miami and New York, pending approval.

On November 18, FAA clears the Boeing 737 MAX to return to the skies.