Originally named Chicago Air Park, Midway Airport was built on a 320-acre (130 ha) plot in 1923 with one cinder runway mainly for airmail flights. In 1926, the city leased the airport and on December 12, 1927 named it Chicago Municipal Airport. By 1928, the airport had twelve hangars and four runways, which were lit up for night operations. A major fire early on June 25, 1930, destroyed two hangars and 27 aircraft, "12 of them tri-motor passenger planes." The loss was estimated at more than two million dollars. The destroyed hangars belonged to the Universal Air Lines, Inc. and the Grey Goose Airlines, the latter under lease to Stout Air Lines. The fire followed an explosion of undetermined cause in the Universal hangar. In 1931, a new passenger terminal opened at 62nd St; the following year the airport claimed to be the "World's Busiest" with over 100,846 passengers on 60,947 flights. (The July 1932 Official Aviation Guide (OAG) shows 206 scheduled airline departures a week.) More construction was funded in part by $1 million from the Works Progress Administration; the airport expanded to fill the square mile in 1938–41 after a court ordered the Chicago and Western Indiana Railroad to reroute tracks that had crossed the square along the northern edge of the older field. The March 1939 OAG shows 47 weekday departures: 13 on United, 13 American, 9 TWA, 4 Northwest, and two each on Eastern, Braniff, Pennsylvania Central, and C&S. New York's airport (Newark, then LaGuardia by the end of 1939) was then the busiest airline airport in the United States, but Midway passed LaGuardia in 1948 and kept the title until 1960. The record-breaking 1945 Japan–Washington flight of B-29s refueled at the airport on their way to Washington, DC. In July 1949, the airport was renamed after the Battle of Midway. That year, Midway saw 3.2 million passengers. In 1959, passenger count peaked at 10 million. The diagram on the January 1951 C&GS approach chart shows four parallel pairs of runways, all 4,240 feet (1,290 m) or less, except for the 5,730-foot (1,750 m) runway 13R (current runway 13C) and the 5,230-foot (1,590 m) runway 4R. The April 1957 OAG shows 414 weekday fixed-wing departures from Midway: 83 American, 83 United, 56 TWA, 40 Capital, 35 North Central, 28 Delta, 27 Eastern, 22 Northwest, 19 Ozark, 11 Braniff, 5 Trans-Canada, and 5 Lake Central. Air France, Lufthansa, and REAL (of Brazil) had a few flights per week. Midway, being surrounded by buildings on all sides, meant that the airport was unable to expand; its runways were too short to safely handle larger four-engine jetliners (the Boeing 707 and the Douglas DC-8) that appeared in 1959. Instead, Chicago jet flights were directed to use O'Hare, which had opened to airlines in 1955. Lighter aircraft like turboprops Lockheed L-188 Electra's and Vickers Viscounts could have continued to fly out of Midway, but O'Hare's new terminal opened in 1962, allowing airlines to consolidate their flights. From July 1962 until July 1964 when United returned, Midway's only scheduled airline was Chicago Helicopter. In August 1966, a total of four fixed-wing arrivals were scheduled, all United 727s (United was alone at Midway until early 1968). By 1967, reconstruction began at the airport, adding three new concourses with 28 gates and three ticket counters, and in 1968, the city invested $10 million in renovation funds. (For a few months during the 1967 renovation, Midway had no scheduled airline flights.) The funds partly supported construction of the Stevenson Expressway, and Midway saw the return of major airlines that year, with 1,663,074 passengers on smaller-capacity, shorter range twin-jet and trijet airliners such as the McDonnell Douglas DC-9, BAC One-Eleven, Boeing 727, and Boeing 737 that could use Midway's runways, which the Boeing 707 and Douglas DC-8 could not. In 1982, the city of Chicago purchased Midway Airport from the Chicago Board of Education for $16 million.