Challenger 601 airplane model. Troubles with the Avco Lycoming powered Challenger 600 led Canadair (now a division of Bombardier) to develop a vastly improved variant in the form of the General Electric CF-34 powered Challenger 601. Another important change was the addition of winglets, which are also offered as a retrofit to earlier aircraft. The 601 first flew on April 10 1982 and for a time was offered alongside the 600. The 600 was dropped from the model line in 1983.