Boeing Ditches Chevrons on 777X Engines Amid Noise Compliance Shift

Boeing has made a strategic shift away from using chevrons on its aircraft engines. The company is removing the jagged nozzle edges, also known as chevrons, from its 777X engines. This decision follows the recognition that modern engine designs can meet noise regulations without incurring aerodynamic penalties.

Chevrons were originally introduced by NASA to reduce noise levels by up to six decibels on Boeing's 787 and 737 MAX models. However, they incurred a thrust penalty of 0.25-0.5% and added drag.

The omission of chevrons from the 777X engines suggests that engine makers can now achieve noise compliance through improved fan blade design and higher bypass ratios. This shift is likely to result in slightly improved fuel efficiency and range on 777X flights, benefiting airlines with lower operating costs and communities near airports experiencing quieter operations.