N999SQ

Started operations under Swissair in 1951 for seventeen years before transferring to Sterling Airways. Went to Concare Aircraft Leasing and changed tail numbers to N515AO and then to N515EA in 1973. In 1976, it received a new tail number N999SQ and served as a fire plane, Sis-Q Flying Service #51, and earned a certificate of airworthiness. From 1985-2000, it served for Macavia International Corporation, T and G Inc, and finally Everts Air Fuel at Fairbanks International Airport, AK until retirement in 2000. Everything was scrapped except for the front frame, which got moved to Pikes Aviator Greenhouse and Sweets.