After two fatal crashes involving the Boeing 737 Max affected public trust in the brand, questions arose about the aircraft’s design. The crashes exposed underlying issues, many tracing back to the size of the CFM International LEAP high-bypass turbofan engines selected for the plane. Boeing positioned these large engines unorthodoxly, raising concerns about their impact on the aircraft’s performance and safety.
CFM International, a collaboration between GE Aerospace and Safran Aircraft Engines, produces the LEAP engines, which also power other aircraft such as the COMAC C919 and Airbus A320neo. Despite successful use on these planes, the larger size of the 737 Max’s engines necessitated unique adaptations by Boeing. The company was eager to compete with Airbus, whose A320neo had a head start in the narrowbody market.
The LEAP engines offer significant fuel savings and emission reductions. Safran Group reports a 15% reduction in fuel consumption and CO2 emissions compared to older engines. While the A320neo showcased the advantages of the new engines, Boeing faced challenges adjusting the 737 Max to fit them.
Boeing’s approach avoided extensive design changes that would require new certification, resulting in modifications seen as contributing to the crashes. The Maneuvering Characteristics Augmentation System (MCAS), introduced to compensate for the altered engine placement, has been linked to both accidents. Incorrect responses from the system resulted in 346 fatalities, raising scrutiny about Boeing’s safety protocols and corporate decisions.
Investigations revealed a pressured culture within Boeing, prioritizing cost-cutting measures, leading to unsafe practices. Whistleblowers have exposed these issues, influencing lawsuits and settlements, such as the last-minute agreement to avoid a civil trial over the Ethiopian Airlines crash.
The design decision to keep the 737 Max low to the ground has operational benefits, including easier ground handling, faster turnarounds, and greater cost efficiency. However, the low engine placement increases the risk of foreign object damage from debris.
As of March 2025, Boeing has produced 1,784 units of the 737 Max, indicating its enduring appeal despite setbacks. The FAA is currently auditing Boeing to address the aircraft’s safety concerns, suggesting potential resolutions are forthcoming.
