Boeing 737 Max to Fly Again, Clouded by Certification Concerns

Boeing 737 Max to Fly Again, Clouded by Certification Concerns

INSIGHTi
Boeing 737 Max to Fly Again, Clouded by
Certification Concerns
December 7, 2020
On November 18, 2020, the Federal Aviation Administration (FAA) issued an order rescinding its March
2019 order that had grounded the Boeing 737 Max passenger jet for nearly 20 months. Congress
continues to debate legislation (H.R. 8408, S. 3969, and S. 3866) seeking to reform aircraft certification in
an effort to avoid future safety stand-downs of this magnitude involving the design of highly complex
transport aircraft.
Two high-profile fatal accidents, the crash of Lion Air flight 610 in October 2018 and the crash of
Ethiopian Airlines flight 302 in March 2019, prompted the unprecedented worldwide grounding of the
737 Max as investigators and engineers sought to identify and remedy a common set of causes. Both
accidents were linked to an automated flight control system feature cal ed the Maneuvering
Characteristics Augmentation System (MCAS). The design of the 737 Max included larger engines than
earlier versions of the 737. Under certain circumstances, these engines could cause an unintended pitch up
of the airplane’s nose. MCAS was instal ed to automatical y compensate for this undesirable tendency. In
both accidents, MCAS activated repeatedly, resulting in extreme nose-down pitching. Analysis after the
accidents revealed that MCAS relied on a single sensor that was reportedly prone to damage, and that the
aircraft lacked safeguards to prevent its activation if that single sensor failed. The two crashed airplanes
had no cockpit indicators to notify pilots of a possible sensor failure, and Boeing had not advised airlines
to train pilots about the existence and functioning of MCAS or proper procedures to override or disable it
if necessary.
Design Certification Probed
The crashes triggered a number of investigations and reviews of FAA’s procedures for certifying the
safety of the 737 Max in particular and of passenger aircraft more broadly. FAA joined with aviation
authorities from other countries and the European Union to complete a comprehensive technical review of
the Boeing 737 Max flight control system design and certification. The Department of Transportation
independently convened a special committee to review the certification of the Boeing 737 Max, which
urged FAA to require aircraft manufacturers to implement Safety Management Systems (SMS) like those
already required of airlines. While FAA initiated rulemaking back in 2014 to comply with international
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standards requiring SMS at aircraft design and manufacturing organizations, FAA and industry had settled
on voluntary implementation of an SMS standard rather than a mandatory requirement.
A House Transportation and Infrastructure Committee investigative report found, in addition to faulty
design and performance assumptions specific to the Boeing 737 Max, a “culture of concealment” at
Boeing that contributed to withholding critical details from FAA, airlines, and pilots. It concluded that
FAA had insufficient oversight over the aircraft’s development after delegating significant aspects of
certification to Boeing itself under the Organization Designation Authorization (ODA) program. The
report also concluded that schedule, cost, and production pressures at Boeing further compromised safety.
Grounding Order Lifted
FAA’s November 18 order requires Boeing 737 Max operators in the United States to take certain
corrective actions detailed in Airworthiness Directives to address identified MCAS flaws before the
airplanes can return to service. It also requires airlines to develop FAA-approved pilot training regarding
the MCAS system and its functionality, including flight simulator training to help pilots respond to
MCAS failures. American Airlines reportedly plans to resume some 737 Max flights by late December
2020, while United Airlines and Southwest Airlines reportedly plan to reintroduce the jet in early 2021.
Air safety agencies in some other countries and the European Union grounded the 737 Max prior to
FAA’s action in 2019, leading to speculation that they might impose stricter conditions than FAA before
al owing the aircraft to reenter service. However, the European Union Aviation Safety Agency (EASA),
along with its counterparts in Canada and Brazil, has reportedly mostly harmonized with FAA in setting
conditions for returning the 737 Max to service, al aying concerns over potential y lengthy disagreements
among international regulators. It remains to be seen whether foreign regulators wil scrutinize aircraft
certification more closely in the future and rely less on FAA’s determinations.
Legislation Seeks Certification Reforms
On November 17, 2020, the House passed the Aircraft Certification Reform and Accountability Act (H.R.
8408). The bil would require each aircraft manufacturer to develop and implement an FAA-approved
SMS that includes a confidential, nonpunitive safety reporting program for employees to voice safety
concerns and to follow a code of ethics setting safety as the company’s top priority. It would also order an
expert review of al ODA holders that manufacture transport category airplanes. The review would assess
the extent to which those manufacturers have implemented a safety culture, the effectiveness of measures
implemented to prioritize safety, and each company’s capability to make reasonable and appropriate
decisions regarding certification functions delegated by FAA under ODA.
Similarly, the Aircraft Safety and Certification Reform Act of 2020 (S. 3969) would mandate changes to
the aircraft certification process, the ODA program, and FAA oversight of that program. The bil would
mandate implementation of FAA-approved SMS for aircraft manufacturers. It would additional y require
that FAA review and approve al personnel assigned to an aircraft manufacturer’s ODA unit, and would
increase FAA involvement with and oversight of ODA activities. The bil would direct FAA to convene an
expert panel to review ODA best practices and to address the panel’s findings and recommendations. It
would also require FAA to review and update existing requirements and guidance regarding human
factors and human systems integration, particularly those related to aircraft-pilot interfaces. A separate bil
under consideration in the Senate, the Aircraft Safety Improvement Act of 2020 (S. 3866), would
similarly require aircraft manufacturers to implement SMS, and would require FAA to identify and
implement ODA best practices and address human factors considerations in the design of aircraft
automation.

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Author Information

Bart Elias

Specialist in Aviation Policy

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