Boeing CC-137

CC-137
A Canadian Armed Forces Boeing 707 (CC-137)
Role	Military transport aircraft
Manufacturer	Boeing
First flight	1970
Introduction	1972
Retired	1997
Primary user	Canadian Forces
Number built	5
Developed from	Boeing 707

The Boeing CC-137 is the designation for five Boeing 707-347C transport aircraft which served with the Canadian Forces from 1970 to 1997. The aircraft provided long range passenger transport for the military, VIP transport for government and air-to-air refueling for fighters such as the CF-116 Freedom Fighter and CF-18 Hornet. It was replaced by the Airbus CC-150 Polaris in the transport role and much later in the tanker role.

During the 1960s, the Royal Canadian Air Force set out a requirement to replace the aging fleet of Canadair CC-106 Yukons and Canadair CC-109 Cosmopolitan transports. Initially, the Boeing KC-135 was being considered because the versatile design could also fulfill a yet-unspecified aerial refuelling role. Although a "purpose-built" aircraft would have suited the RCAF requirements better, an opportunity to acquire Boeing 707s as an alternative, soon presented itself.

Canada purchased five Boeing 707s in 1970-71 to replace the RCAF's CC-106 Yukons in the long range transport role and the CC-109 Cosmopolitan as an executive or short-range transport. The first four aircraft had been built for Western Airlines, but that order was subsequently cancelled; the fifth was bought separately a year later. To fulfil Canada's requirements for aerial refueling, two aircraft were fitted with Beechcraft made probe and drogue refueling pods in 1972. The two sets of refuelling equipment was moved from aircraft to aircraft to keep fleet utilization even between the airframes.

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