Several bases closed during the 1970s–1990s as aircraft changes took place. As CF-18A/B Hornet tactical fighter bombers were acquired, CF-104 Starfighter and CF-101 Voodoo aircraft were retired in the early-mid-1980s, leading to the closing of CFB Chatham and CFB Baden Soellingen and various bombing ranges. The CF-116 fighter aircraft and Boeing 707 transport/refuelling aircraft were retired. Also, over the years, the stations of the three radar early warning lines were modernized or closed. In the late 1970s AIRCOM replaced the CP-107 Argus and CP-121 Tracker with the CP-140 Aurora/CP-140A Arcturus maritime patrol aircraft.