Regular air passenger service to Portland and Boston was begun in 1931 by Boston-Maine Airways, owned by the Boston and Maine and Bangor and Aroostook railroads and under contract to Pan American, which was interested in the airport as a stop on its planned intercontinental air route between the U.S. and Europe. Amelia Earhart was a celebrity pilot on some of the earliest flights for Boston-Maine Airways in the 1930s. The airport was equipped with floodlights for night flights as early as 1937. In 1940, Boston-Maine became Northeast Airlines, which eventually merged with Delta Air Lines in 1972.