20th century

Bangor International Airport began as Godfrey Field in 1921, on land owned by local attorney Edward Rawson Godfrey (1877–1958). On August 19, 1923, 15 Martin Bombers and 11 DeHaviland Scout Planes under the command of Gen. Billy Mitchell — virtually the entire U.S. Army Air Corps — landed there on a practice mission.

Regular air passenger service to Portland and Boston began 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 travelled to Bangor on the first flight of Boston-Maine Airways, in which she was an investor, in 1933. 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.

1941 saw the first fatal crash of a military aircraft in Maine, when a Douglas B-18 Bolo bomber stationed at Bangor Army Airfield went down in nearby Springfield, killing all four crew. Between 1941 and 1971, there were 14 additional fatal crashes of military aircraft based in Bangor, three within city limits and the rest in small towns or wilderness areas between the north woods and the coast.

Just before World War II, Godfrey Field was taken over by the Army Air Corps and became the Bangor Army Air Field. It was operated until 1968 as Dow Air Force Base, and still later as Bangor Air National Guard Base.

In 1948, Bangor was one stop on the round-the-world flight of Richarda Morrow-Tait, the first woman to pilot a plane around the globe. She landed at Dow but took off for the next leg (to Canada) from the airport in nearby Old Town. The Canadian authorities refused her permission to hop the Atlantic and ordered her back to Bangor. She defied them and completed the trip.

In 1958, the Air Force constructed its current 11,440 ft runway for the B-52 Stratofortress. At the time, it was the longest runway on the east side of the Mississippi River.

In the 1950s and 1960s, Bangor was a destination for Northeast Airlines before its merger into Delta. Northeast usually used the Douglas DC-6 for service between Bangor and Boston and New York. In 1965, there was still a single weekly DC-3 flight to Bangor operated by Northeast Airlines.

In 1968, Dow AFB was closed as an active duty Air Force installation. Most of the base was purchased by the city and reopened the following year as Bangor International Airport. The portion of Dow AFB not turned over to the city became the basis for the current Air National Guard Base and the Maine Army National Guard's Army Aviation Support Facility.

In October 1969, Trans World Airlines Flight 85 which had been hijacked in California refueled in Bangor on its way to Rome, where the hijacker was captured.

From the 1970s into the 1990s, the airport attracted 3,000 to 5,000 commercial flights a year, mostly charter jetliners flying between Europe and the West Coast of the United States, or the Caribbean and Mexico. Bangor was a logical refueling stop, and as a U.S. port of entry, passengers could go through customs and immigration checks while their plane was being serviced. Travelers from every part of the world mingled in the airport lounge — from the French and Belgian contingents of the Elvis Presley Fan Club on their way to Memphis to President José López Portillo of Mexico on his way to Moscow with members of his military staff. Laker Airways, World Airways, Lot Polish Airlines, Aeroméxico, British Airways, Balair, Condor Airlines, LTU International, Capitol International Airways, Aeroflot, and Pan American were a few of the companies whose livery became common in the skies above Bangor. Finnair briefly used Bangor as a hub for regularly scheduled daily flights.

Bangor also had mainline scheduled jets on Northeast Airlines, and subsequently Delta in the 1970s with flights to Portland and Boston. By the 1980s, USAir and United also began mainline service into BGR. Continental briefly had 1 mainline MD-80 jet to Newark Liberty International Airport in 1991–1992 to complement their propjet Continental Express service to Newark and Presque Isle.

In 1977, Erwin Kreuz, a 50-year-old West German brewery worker on his way to San Francisco, stepped off a refueling charter flight in the mistaken belief that he had reached his destination. Speaking no English, he spent four frustrating days in Bangor looking for San Francisco landmarks before realizing he was not in California. When his story made local and then national news, Bangorians were so delighted with his error that he received the key to the city, met the governor of Maine, was made an honorary member of the Penobscot Indian tribe, received a marriage proposal, and was given a gift of local land. The San Francisco Chronicle paid his way to California, where he was similarly feted, and he was invited back to Bangor the following year to help open the Bangor Mall.

In 1980, major renovations were launched to the airport.