Southwest Airlines is planning to cut about one-third of its flights in Atlanta next year to save money, and employees affected by the change are furious.

Southwest Airlines Co. is ending nearly a third of its flights through Atlanta in an effort to eliminate unprofitable routes, the latest move by the carrier to improve operations amid pressure from an activist investor.

The changes come a day before Southwest's investor day, when executives will map out the company's plan to cut costs and grow revenue.