Southwest Airlines

Southwest Airlines has operated a single aircraft type for over 50 years, while every other major airline runs a mixed fleet of Boeing and Airbus models in various sizes. Southwest flies only the Boeing 737. Every pilot is qualified on the same plane. Every mechanic is trained on the same engine. Every gate is configured for the same fuselage. This decision made by founder Herb Kelleher in the 1970s eliminated an astonishing amount of operational complexity and is the foundation of everything that followed. The operational simplicity generates savings at every level. Pilot training costs drop because there is no need for tight rating conversions. Spare parts inventory shrinks because one set of component services the entire fleet. Aircraft can be swapped at the last minute without crew scheduling chaos. Gate turnaround times can fall below 25 minutes among the fastest in the industry because ground crews know exactly what they are dealing with every single time.