nickel aluminium bronze controllable pitch propellers are designed to transmit of power per shaft to the water and produce a combined static bollard pull of about . For onboard electricity production, the ship has two Caterpillar 3512 series ship service diesel generators and a single Caterpillar 3406 DITA emergency diesel generator. In addition, both reduction gearboxes are fitted with clutched power take-offs for 1,250kVa shaft alternators that supply power to the stern thruster and air bubbling system compressors. In line with her original Canadian Arctic Shipping Pollution Prevention Regulations (CASPPR) Arctic Class 4 rating, Terry Fox is designed to break at least first-year level ice with a continuous speed of . During icebreaking operations, the ice friction is reduced by lubricating the hull-ice interface with a low-pressure air bubbling system developed by Wärtsilä. In open water, the system can also act as a bow thruster and used for maneuvering together with the ship's single centerline rudder and a transverse stern thruster. When operating in ice-free waters, the ship was designed transit at an economical speed of about with just two main engines, but her maximum speed is quoted as . Career Terry Fox (1983–1991) Between 1983 and 1990, BeauDril's mobile drilling units drilled a total of nineteen exploratory wells in the Canadian part of the Beaufort Sea with the support of Terry Fox and other icebreaking vessels: nine with the Mobile Arctic Caisson Molikpaq and ten with the Conical Drilling Unit Kulluk. Twelve wells alone were drilled in the Amauligak prospect, the most significant oil and gas field discovered in the region, but the high expectations for the Beaufort Sea were not met: the area was characterized by a large number of small, widely scattered resources. Molikpaq was mothballed after completing the last well in 1990. On 1 November 1991, Terry Fox was leased to the Canadian Coast Guard for two years to replace the decommissioned during the extensive modernization of . During the leasing period, the icebreaker was found to meet Canadian Coast Guard's needs satisfactorily, and the vessel was purchased from Gulf Canada Resources on 1 November 1993. Around the same time, the majority of BeauDril's fleet was purchased by Canadian Marine Drilling (Canmar), the drilling subsidiary of Dome Petroleum (later Amoco Canada) that had been Gulf Canada's main competitor in the Beaufort Sea for more than a decade. CCGS Terry Fox (1991–present) Under the Canadian Coast Guard,