The McDonnell CF-101 Voodoo was an all-weather interceptor aircraft operated by the Royal Canadian Air Force and the Canadian Forces between 1961 and 1984. They were manufactured by the McDonnell Aircraft Corporation of St. Louis, Missouri for the United States Air Force (as F-101s), and later sold to Canada. CF-101s replaced the obsolete Avro CF-100 Canuck in the RCAF's all-weather fighter squadrons. The Voodoo's primary armament was nuclear AIR-2A Genie unguided air-to-air rockets, and there was significant political controversy in Canada about their adoption. Although they never fired a weapon in wartime, the CF-101 served as Canada's primary means of air defence from Quick Reaction Alert facilities at Canadian airbases. The CF-101s were retired in the 1980s and replaced with McDonnell Douglas CF-18 Hornet fighters. Many examples are preserved in museums and parks in Canada and the United States. Acquisition Origins After the cancellation of the CF-105 Arrow program in February 1959, George Pearkes, the Canadian Minister of National Defence officially maintained that the existing Avro CF-100 interceptors and the Bomarc missiles that had been ordered in September 1958 would be adequate for Canada's air defense needs. Unofficially, it was recognized that there was still a bomber threat, and discussions had been underway since before the formal conclusion of the Avro Arrow program concerning the RCAF acquiring an "off-the-shelf" interceptor from the United States. The USAF indicated that it was prepared to make 56 F-101B interceptors and 10 F-101F trainers available (by employing Convair F-102 Delta Daggers in less demanding NORAD sectors) for Canadian purchase. The deal was delayed for over a year by negotiations over acquisition costs and offsets, as well as debate within the Diefenbaker government about Canada adopting nuclear weapons systems, which had been agreed to, in principle, in 1958. The financial arrangements were sorted out by Canada taking over the staffing and funding of 11 Pinetree Line radar stations within Canada that had formerly been operated and funded by the USAF. A detailed agreement signed in June 1961 covered the transfer of the aircraft, meant to equip five front-line squadrons (replacing nine CF-100 squadrons) and an Operational Training Unit (OTU). Nuclear weapons controversy The issue of nuclear weapons in Canada had not been resolved in June 1961, thus the CF-101s were armed only with their secondary AIM-4D Falcon missiles. In April 1963, the issue led to the collapse of the Diefenbaker government. The succeeding Pearson government