Gerald AFAIK every air carrier airport in the country leases in one way or another their terminal and gates spaces. Every project I have been involved in has been 90% Federal and 10% local funding. I know of a time when United wanted to build their own concourse at Cleveland with I think 22 gates but the City of Cleveland turned them down. They said they wanted to be able to say they had X number of gates available. Airlines may have structures on airports such as maintenance hangars they own but they have been used to having the airport operators build them for them. I'd have to research but there is a possibility United built their two terminals at O'Hare. Al Al