In this Tuesday, Aug. 8, 2017, photo,a Delta Air Lines airplane is seen on the tarmac as an American Air Lines takes off from LaGuardia Airport in the Queens borough of New York. (AP Photo/Mary Altaffer) ATLANTA — Delta Air Lines is joining two rivals in raising fees to check a bag on a flight within the United States. Delta on Wednesday posted new fees of $30 for checking a first bag and $40 for a second bag — increasing the previous fees by $5 each. The changes match increases recently imposed by United Airlines and JetBlue Airways. By midday, American Airlines had not increased bag fees. Southwest Airlines lets passengers check up to two bags free. Airlines have been pulling in more revenue from extra charges for several years. Last year, U.S. carriers raised $7.4 billion from fees on checked bags and ticket changes, led by American, Delta and United.