At first glance, the Boeing 737 MAX appears similar to earlier models in the 737 family. However, one of its most significant changes is the increased height of its landing gear. This adjustment was not for appearance but stemmed from engineering needs as Boeing sought to modernize the aircraft while retaining its legacy design.
The original 737, introduced in 1967, was designed with short landing gear to allow ground crews easy access without specialized equipment. This made it practical for smaller airports lacking advanced infrastructure. The low-slung body was possible because early engines were smaller and fit comfortably under the wings.
As engine technology advanced, Boeing upgraded to larger engines with each new series. For the 737 Classic, engineers flattened the engine nacelle to maintain ground clearance. However, when developing the 737 MAX, Boeing adopted even larger and more efficient LEAP-1B engines from CFM International. These engines had a fan diameter about eight inches larger than those on previous models and provided roughly 15–20% better fuel efficiency. Their size meant they could not fit under the existing wing configuration without risking safety standards due to reduced ground clearance.