A Convair 440 delivered to United Airlines as N73138 Mainliner Boise in June 1953, Lake Central Airlines would take over the aircraft in 1961 and upgrade it to a CV580 in 1967. Great Lakes Airlines would buy the aircraft from the airline, then known as Allegheny, in 1976. A name change to Air Ontario in 1986 after becoming an Air Canada connector, the airliner was sold to Canair Cargo in 1980 for their freight operation. Last operated by Renown Aviation from 1995 until stored at Roswell NM and the registration cancelled in 2002. Last known still stored there in poor condition.

It had recently been acquired by Canair Cargo but was still in basic Air Ontario colours.

Built for United as a CV340-31, N73138, and delivered 6/53. Sold to Lake Central 3/61 and converted to 580 3/67. Other regns were N5846 and N203RA.