there was no separation of incoming and outbound passengers and no thought given to future expansion, though this did not stop Newark from being the busiest commercial airport. United Airlines, American Airlines, Eastern Airlines, and TWA signed 10-year leases with the airport which ended in 1938. Then they would pay on a month-to-month basis until LaGuardia Airport opened in December 1939; by mid-1940, all passenger airlines had left Newark, no longer making it the world's busiest airport. During World War II, the field was closed to commercial aviation while it was taken over by the United States Army for logistics operations. In 1945, captured German aircraft brought from Europe on HMS Reaper for evaluation under Operation Lusty were off-loaded at Newark and then flown or shipped to Freeman Field in Indiana or Naval Air Station Patuxent River in Maryland. The airlines returned to Newark in February 1946. In 1948, the city of Newark leased the airport to the Port of New York Authority (now the Port Authority of New York and New Jersey). As part of the deal, the Port Authority took operational control of the airport and began investing heavily in capital improvements, including new hangars, a new terminal and runway 4/22. On December 16, 1951, a Miami Airlines C-46 bound for Tampa lost a cylinder on takeoff from runway 28 and crashed in Elizabeth, killing 56. On January 22, 1952, an American Airlines CV-240 crashed in Elizabeth while on approach to Runway 6, killing all 23 aboard and seven on the ground. On February 11, 1952, a National DC-6 crashed in Elizabeth after takeoff from runway 24, killing 29 of 63 on board and four on the ground. Inevitably, the airport was closed for some months; airline traffic resumed later in the year, but the airport's continued unpopularity and the New York area's growing air traffic led to searches for new airport sites. The Port Authority's proposal to build a new airport at what is now the Great Swamp National Wildlife Refuge was defeated by local opposition. Through the early 1970s, Newark had a single terminal building located on the north side of the field by what is now Interstate 78. A new control tower opened in 1960, and the terminal was expanded from 26 to 32 gates in 1965. A $200 million expansion of the airport, which was to include three terminals, began in 1967 after three