an airport. The RFC sold the airport to the University of Michigan in 1947 for $1.00. The terms of the sale required that the university operate the airport as a research facility, and the Michigan Aeronautical Research Center (later renamed Willow Run Research Center) took over some of the airport's buildings that were not needed for commercial aviation operations. For a time, the university housed some of its students in the apartments previously used by plant workers. Many of the buildings at the airport were used by University of Michigan physicists and engineers in research for national defense, including early work in antiballistic missile defense and remote sensing, at a facility which would become the Environmental Research Institute of Michigan (ERIM) after separating from the university in 1972. At about the same time it sold the airfield, the RFC leased (and later sold) the bomber plant to the Kaiser-Frazer automobile company; the factory eventually became owned by General Motors. The last GM operations at Willow Run ended in 2010, and that property is planned for redevelopment after 2013 by its owner the RACER Trust. Since April 2013, there has been an effort underway by preservationists to save a small portion of the original bomber plant facility, adjacent to the airport, as a new home for nearby Yankee Air Museum. The campaign is called SaveTheBomberPlant.org and is centered on a website of the same name. In 1951, the United States Air Force exercised a right of return to Willow Run and established Willow Run Air Force Station to the east of the airport runway. Willow Run AFS closed in 1959. Decline of Willow Run Almost all of Detroit's scheduled airline flights used Willow Run until 1958, when the coming of the Jet Age drove traffic to the Romulus airfield, which that year had been renamed Detroit Metropolitan Wayne County Airport (the name it still bears). It offered carriers a new terminal designed for the new aircraft, a newly expanded runway layout, and approach controls that made it the first inland airport in the country certified for jet airliners. In 1956, there were seven passenger airlines at Willow Run. The April 1957 Official Airline Guide shows 68 weekday departures on Capital, 45 on American, 23 on Eastern, 17 on Northwest Orient, 14 on United, 13 on North Central, 13 on TWA, 8 on Delta, 5 on Allegheny and 3 on Mohawk. American's