FAA Grants Boeing Exemption for 737-7 Max Certification Despite Stall-Management System Non-Compliance

Boeing has secured an exemption from the Federal Aviation Administration (FAA) that paves the way for the certification of the 737-7 Max, even though its stall-management system falls short of certain certification requirements. This development has sparked discussions surrounding aviation safety and the protocols for certifying commercial aircraft.

On September 19 2023, the FAA granted an exemption concerning lightning and radiation regulations for the 737-7. However, it mandated that operational MAX 7 aircraft must install an updated “stall management yaw damper” (SMYD) by March 1, 2027. The SMYD is a critical hardware and software system that provides essential data to the aircraft’s stall warning system.

Boeing’s plan is to develop a certification-compliant SMYD as part of its work on certifying the 737-10 and subsequently incorporate these updates into other variants, with the MAX 7 expected to achieve certification this year, followed by the MAX 10 next year.

Boeing’s Stance
Boeing defended its request for the exemption, asserting that it sought FAA approval to certify the 737-7 with an updated SMYD based on its “well-established safety track record.” The company also highlighted minor software adjustments to the SMYD to align it with the MAX 7’s shorter fuselage.

In a letter to the FAA in June, Gary Hamatani, Boeing’s 737 Max development chief project engineer, detailed specific software updates to the SMYD, including those related to stall warning, stall identification schedules, yaw damper filter and schedule coefficients, and gain schedules. However, it was only later discovered that the system did not comply with certification rules related to lightning and radiation exposure.

FAA Evaluation and Concerns
During its investigation, Boeing informed the FAA that SMYD failures due to lightning or radiation exposure could potentially lead to “rudder oscillation.” The FAA classifies this as a “catastrophic failure” since it could result in a “hard-over condition” exceeding structural load limits.

Nevertheless, the FAA, in its September 19 approval, concurred with Boeing’s assessment that the risk of SMYD failure due to lightning or radiation was exceedingly low. The agency considered the scenario as “not practically feasible” and thus granted the certification exemption.

The FAA’s decision has raised concerns in both the aviation industry and among the public. Critics argue that granting an exemption for a crucial system like the SMYD, even with a minimal perceived risk, establishes a precedent that may compromise safety standards. The imperative of ensuring full compliance with certification requirements cannot be understated, as it directly impacts passenger safety.

Boeing’s commitment to addressing SMYD non-compliance through the development of a certification-compliant system for the 737-10 is seen as a positive step. Nevertheless, questions linger about why these issues were not identified earlier in the certification process and whether other potential safety risks have been overlooked.

The FAA’s decision to grant an exemption for the 737-7’s certification, despite its stall-management system non-compliance, has ignited debates regarding aviation safety standards. While Boeing is dedicated to resolving the issue, this incident underscores the necessity for rigorous scrutiny and adherence to safety regulations during the aircraft certification process. As Boeing continues its pursuit of certification for the 737-7 and 737-10, the aviation industry will vigilantly monitor developments to ensure passenger safety remains the top priority.

Sources: AirGuide Business airguide.info, msn.com, 100knots.com