United Airlines pilot Steve Lindland receives a COVID-19 vaccine from RN Sandra Manella at United's onsite clinic at O'Hare International Airport on March 09, 2021 in Chicago, Illinois.
Scott Olson—Getty Image

As COVID-19 cases spiked in the U.S. last summer, United Airlines took the bold step of requiring its workers to get vaccinated, even before the Biden Administration mandated such rules. While some employees scoffed at the mandate, 99.7% got their shots, and only one coronavirus-related death has been reported among that group. Many of United’s rivals have followed suit. “Some are mad at me still,” says CEO Scott Kirby. “But they’re alive.” Kirby is also pursuing greener flying; United recently flew a 737 Max from Chicago to Washington with one engine running on cooking oil and grease to promote alternative fuels.

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