United Airlines Ventures, the carrier’s investment vehicle, through its Sustainable Flight Fund has invested in carbon-capture company Heirloom, the airline announced Tuesday. Additionally, the carrier agreed to fund the removal of up to 500,000 tons of carbon dioxide, which would be delivered for the production of sustainable aviation fuel or “permanently stored underground,” according to United. 

Terms of the investment were not immediately disclosed.

Heirloom is a direct air capture company, meaning it removes atmospheric CO2, according to United. Other carbon-capture companies target removal of carbon from a specific emitting source, such as a power plant. 

United also in March 2023 invested $5 million in carbon-capture company Svante, and prior to the formation of the UAV Sustainable Flight Fund, made a “multimillion-dollar investment” in 1PointFive, another carbon-capture company.

The UAV Sustainable Flight Fund, launched in 2023, has more than $200 million in funding commitments from United and its corporate partners to support startups focused on decarbonizing air travel.