Allegheny County Airport is in West Mifflin, Pennsylvania, 7 miles (11 km) southeast of Pittsburgh. It is the fifth-busiest airport in Pennsylvania following Philadelphia, Pittsburgh, Allentown, and Harrisburg. The airport is owned by the Allegheny County Airport Authority and is the primary FAA-designated reliever airport for Pittsburgh International Airport. Allegheny County Airport was dedicated on September 11, 1931. When it was completed, it was third-largest airport in the country and the only hard-surface airport in the country. It was historically the main entrance to metro Pittsburgh via air from its inception until June 1952, when the Greater Pittsburgh Airport (now Pittsburgh International Airport – KPIT) opened for commercial aviation. Like many historic municipal fields, Allegheny serves small and mid-sized private, corporate and commercial traffic well, but was not built to handle jet airliners. A Boeing 727 owned by Rockwell and two DC-9's however were based on the field for years. One DC-9, owned by Westinghouse Air Brake, operated from the former TWA hangar. Another DC-9 was owned by Richard Scaife. Additionally, political candidates often operate chartered jet airliners into the field. Air Force 2, a Boeing 757, has been on the airport in the 2000s. In May 2017, a Southwest Boeing 737 with 143 passengers en route from Orlando, made a precautionary landing when running low on fuel. The airport is popular among business travelers, being closer to downtown than Pittsburgh International Airport. It is much closer to the densely populated South Hills, Monroeville area and Monongahela Valley. The airport had a Hollywood big screen moment in the 2002 film The Mothman Prophecies, serving as the small Point Pleasant, West Virginia airport where the governor and Richard Gere debate how serious the impending crisis is in the river town. Also the Airport and Terminal were used in the 1986 movie Gung Ho starring Michael Keaton, The 2017 film Last Flag Flying was filmed in the hangar and ramp areas. The airport is home to Pittsburgh Institute of Aeronautics (PIA), a large aircraft maintenance school. Facilities The main terminal was built on a former steel industry slag dump in 1931 by Stanley L. Roush, with later additions by Henry Hornbostel in 1936. Aiming for a more modern design, the building used white brick with touches of black, silver, and green. Hornbostel continued with these colors for his additions. Above the stainless-steel canopy is a semi-hexagonal doorhead. To each side is an