01/22/2007. Remarks by Jack McKillop: "The aircraft was built as a Model 340-31 and was delivered to United Air Lines of Chicago, Illinois, USA, on May 22, 1953 registered N73132 and named "Mainliner Washington". It was sold to Alaska Airlines on April 4, 1962; Charlotte Aircraft Corp. in June 1963; and Frontier Airlines on June 11, 1963; Frontier named it "Sunliner Taos".

In December 1965, Frontier had it converted to a Model 580 by replacing the two reciprocating engines with two Allison turboprop engines. In January 1980, it was sold to Aspen Airways who sold it to ERA Helicopters in August 1980. In 1982, it was reregistered N569JA. It was sold to a Canadian charter company in May 2003 and withdrawn from use and placed in storage at Kelowna, British Columbia. In June 2006 it was seen in a cannibalized state. As of this date, this 580 is still registered to ERA Aviation of Anchorage, Alaska."