The new Boeing aircraft could be argued to be one of the safest in the skies today. 

Background

The Boeing 737 MAX program debuted in August 2011. It was designed as a more modern successor to the 737NG, the previous generation of 737 aircraft which has been around since the late 1960s. The MAX was designed with fuel efficiency, comfort, and renewed technology in mind. 

The first airframes were tested in the mid-2010s and took to the skies at the beginning of 2016. Since the start of the program, Boeing has amassed thousands of orders from airlines all over the world.

In 2017, the first airframe was delivered to Malindo Air in Indonesia, with its first revenue service taking place on May 22, 2017.  In the beginning, there were very few issues with the new MAX aircraft. Passengers praised the quieter engines and airlines were very pleased with the jet's fuel economy, capacity, and overall performance.

Safety Concerns

However, on October 29, 2018, a Lion Air 737 MAX 8 crashed in Indonesia, killing all 189 passengers onboard. The deadly crash led to some very serious investigations by authorities but the findings were unclear. It was known that there were issues with the flight crew's knowledge of the anti-stall system in the aircraft, but the 737 MAX continued to operate until early March 2019, when a second deadly crash occurred in Ethiopia. All 154 passengers were killed in the deadly incident.

Almost immediately, many aviation regulators began to ground the aircraft. By mid-march, no 737 MAX passenger flights were being operated.

Subsequently, the 737 MAX underwent extensive testing to determine the cause of the two crashes. It was later found that the MCAS system — an anti-stall system found only on the MAX — was at fault. Sensors would improperly send data to the aircraft, suggesting an orientation that the aircraft was not in. The aircraft would then attempt to correct the pitch of the nose given the incorrect data, causing the aircraft's nose to pitch down considerably. When coupled with improper training of flight crews on how to use the system, the cause of the crashes became clear.

Soon after, Boeing implemented a second sensor and introduced new software to determine the pitch angle of the aircraft and reduce the likelihood of faulty information. New training was also recommended for flight crews to ensure familiarity with the system.

Due to the intense scrutiny and requirements for the MAX to be recertified by the authorities in many countries, the aircraft did not carry passengers again until the very end of 2020, with most airlines operating scheduled MAX flights by mid-2021 on regular basis. Still, as of April 2023, airlines in China were only recently given the green light to begin MAX operations once again.

Why is it Safe?

Because of the sheer intensity of the scrutiny the aircraft faced, the Boeing 737 MAX could be considered one of the safest in the world. In fact, among the dozens of models of commercial airliners around the world, it is likely the safest due to the amount of regulation testing that took place. The aircraft was in Boeing's view to make the necessary changes, and the company was pressured into prioritizing its safety following the accidents that took place.