European Regulator EASA Ungrounds Boeing 737 MAX

MAX
Credit: Boeing

FRANKFURT—EASA has become the latest regulator to lift the flight ban of the Boeing 737 MAX, issuing a corresponding airworthiness directive (AD) on Jan. 27.

“We have reached a significant milestone on a long road,” EASA executive director Patrick Ky said. “Following extensive analysis by EASA, we have determined that the 737 MAX can safely return to service.” 

Ky stressed the agency’s autonomy in the process, which differed markedly from previous certifications. “This assessment was carried out in full independence of Boeing or the Federal Aviation Administration (FAA) 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.”

EASA had grounded the aircraft in March 2019 following two 737 MAX accidents in less than five months. The AD does not yield any surprises beyond the requirements imposed on Boeing that it had required in the run-up to its decision. Unlike the FAA, EASA allows pilots to switch off the stick shaker circuit breaker under certain conditions to eliminate a source of distraction. It does not allow certain precision approaches. EASA requires: software updates for the Maneuvering Characteristics Augmentation System (MCAS); a new display alert in case the two angle-of-attack (AOA) sensors deliver diverging data; physical separation of wires from the cockpit to the stabilizer trim motor; updated flight manuals and procedures; mandatory training before pilots start flying the MAX again; and updates to initial and recurring training curriculae.

Before aircraft can be returned to service, system tests and an operational readiness flight are obligatory.

Ky emphasized that “this journey does not end here. 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.” Also, “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.”

That is a reference to the addition of a third “synthetic” sensor pulling AOA data from different sources, allowing a comparison with values generated by the two physical sensors. EASA is used to certifying Airbus aircraft which have three physical sensors that enable a vote between the devices in case of discrepancy.

With the EASA AD now published, national authorities are in charge of the implementation along with airlines. “The actual return to service may take some time,” Ky said. “COVID-19 may also have an influence on the pace of return to commercial operations.”

Jens Flottau

Based in Frankfurt, Germany, Jens is executive editor and leads Aviation Week Network’s global team of journalists covering commercial aviation.

Comments

1 Comment
they have slathered over the manual trim issue (use both hands! really, how? - )

And they never addressed a SEIZED trim motor and what it takes to break out the clutch.