Centennial Airport is a public use airport owned by the Arapahoe County Public Airport Authority in the Denver-Aurora metropolitan area, 15 nautical miles (17 mi, 28 km) southeast of downtown Denver, Colorado, United States. Located in Dove Valley, a census designated place in Arapahoe County, the airport's runways extend into Douglas County. Facilities The airport opened on May 12, 1968, as Arapahoe County Airport, and was renamed on July 13, 1984. The new name reflects Colorado's admission to the Union as the 38th state in 1876, the centennial of the United States Declaration of Independence. In 1985 a new control tower was built. It is an international airport with continuous U.S. Customs services and is one of the busiest general aviation airports in the United States with an average of 874 operations per day. The Federal Aviation Administration control tower and associated air traffic control services are continuous; Runway 35R has a Category I Instrument Approach. Centennial Airport covers 1,400 acres (567 ha) at an elevation of 5,885 feet (1,794 m). It has three asphalt runways: 17L/35R is 10,000 by 100 feet (3,048 x 30 m); 17R/35L is 7,001 by 77 feet (2,134 x 23 m); 10/28 is 4,800 by 75 feet (1,463 x 23 m). In 2018 the airport had 337,947 aircraft operations, average 925 per day: 89% general aviation, 10% air taxi, and 2% military. 840 aircraft were then based at this airport: 569 single-engine, 104 multi-engine, 147 jet, and 20 helicopter. Key Lime Air has its corporate headquarters on the airport property. Air Methods previously did as well; it moved to Greenwood Village, Colorado in 2017. The National Plan of Integrated Airport Systems for 2011–2015 categorized the airport as a reliever airport. Cargo destinations Accidents and Incidents On November 19, 1979, a Cessna 500 Citation I operated by National Jet industries, a cargo flight, crashed on an improper IFR approach to runway 34 due to icing conditions. Two of the three occupants died. On July 2, 1984, a Bell 206B helicopter, N3173L, suddenly rolled over and crashed at Centennial Airport, killing the pilot and single passenger. Investigators found that the connector that retained the cyclic stick had broken due to a loose retaining nut, and attributed the accident to improper maintenance, with the manufacturer's inadequate preflight checklist being a contributing factor. Fifteen days after the crash, Bell Helicopter issued a safety notice advising operators to check quick