Charlotte Douglas International Airport is seeking a new airline agreement that would support $2.1 billion in improvements, a major increase over the roughly $460 million capital program tied to its previous agreement. Airport leaders presented the proposal, known as CLT Beyond, to Charlotte City Council on Monday night. They said the new Airline Use and Lease Agreement could take effect Jan. 1, 2027. The current agreement had been due to expire in June, but was extended for a year in May while negotiations continued. The plan includes nearly a dozen projects, with an expansion of Concourse C and a tunnel connecting the expanded area to the main terminal among the major elements. Airport chief business and innovation officer Ted Kaplan described the Concourse C work as the program’s “showstopper.” The proposed 10.5-year agreement would be signed by American, Delta, Frontier, Southwest and United, with the option of a five-year extension. Other airlines that meet the requirements could join during the term. Charlotte Douglas has about 16 carriers overall. The airport is city-owned but operates on its own revenues. Kaplan told council the airport’s aim is to lease out all space in the terminal. American Airlines, which uses Charlotte as its second-largest hub, leases 93 of the airport’s 123 gates. Council has not decided when it will vote on the agreement. Members approved a motion to allow six weeks for review, but Mayor Rob Harrington vetoed it, saying there had not been enough discussion about the proposed timeline. Harrington said he would work with council on a period for reconsideration but was not comfortable setting a specific deadline that night. The agreement would provide the framework for major airport construction, but the council’s review and eventual decision remain ahead. The scale of the proposed program makes the timing and terms of that review consequential for travelers and the city as Charlotte Douglas plans its next phase of growth.