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EASA approves modified versions of Boeing 737 MAX


January 29, 2021
Naomi Szeben

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The European Union Aviation Safety Agency (EASA) gave its seal of approval for the return to service of a modified version of the Boeing 737 MAX, mandating a package of software upgrades, electrical wiring rework, maintenance checks, operations manual updates and crew training which will allow the plane to fly safely in European skies after almost two years on the ground.

“We have reached a significant milestone on a long road,” said EASA Executive Director Patrick Ky in a statement. “Following extensive analysis by EASA, we have determined that the 737 MAX can safely return to service. This assessment was carried out in full independence of Boeing or the Federal Aviation Administration and without any economic or political pressure – we asked difficult questions until we got answers and pushed for solutions which satisfied our exacting safety requirements.  We carried out our own flight tests and simulator sessions and did not rely on others to do this for us.

“Let me be quite clear that this journey does not end here,” he added. “We have every confidence that the aircraft is safe, which is the precondition for giving our approval. But we will continue to monitor 737 MAX operations closely as the aircraft resumes service. In parallel, and at our insistence, Boeing has also committed to work to enhance the aircraft still further in the medium term, in order to reach an even higher level of safety.”

The Boeing 737 MAX was grounded worldwide in March 2019 following the second of two accidents within just six months, which together claimed 346 lives. The root cause of these tragic accidents was traced to software known as the MCAS (Maneuvering Characteristics Augmentation System), intended to make the plane easier to handle. However, the MCAS, guided by only one Angle of Attack (AoA) sensor, kicked in repeatedly if that sensor malfunctioned, pushing the nose of the aircraft downward multiple times. In both accidents, pilots finally lost control of their plane, resulting in a crash with total loss of aircraft.

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EASA’s conditions for Return to Service now met

In the days after the grounding, EASA set four conditions for the return to service of the aircraft:

  • The two accidents (JT610 and ET302) are deemed sufficiently understood
  • Design changes proposed by Boeing to address the issues highlighted by the accidents are EASA approved and their embodiment is mandated
  • An  independent extended design review has been completed by EASA
  • Boeing 737 MAX flight crews have been adequately trained

“These four conditions have now all been met, allowing us to go ahead with the return to service,” Ky said.

To enhance transparency, a closing report released by the Agency explains its approach and the reasoning for its decisions.

While the investigations assessed that the behaviour of the MCAS and related alerting systems were the clear main cause of the two crashes, EASA rapidly realized that a far wider review of the 737 MAX was needed. EASA therefore extended its analysis to the entire flight control system. With a particular focus on the human factors – the actual experience for a pilot of flying the plane.