The Bay class is a class of eight armed patrol boats, built by Austal and used by the Customs Marine Unit of the Australian Customs and Border Protection Service. They entered service during the late 1990s and early 2000s, and are primarily used on border protection duties. The class was due to be replaced by 2010, but a request for tender was not issued until June of that year. The availability of the Bay class ships decreased during the later years of their service life. After the began entering service, four of the Bays were offered to other forces; two each to the Sri Lankan Navy and the Malaysian Maritime Enforcement Agency. Design and construction Bay-class vessels have a displacement of 134 tons, are long, have a beam of , and a draught of . The propulsion system consists of two MTU 16V 2000 M70 diesel engines, supplemented by a VosperThornycroft bow thruster. The patrol boats have a maximum speed of , and a maximum range of . Each vessel is fitted with a 7.62 mm general purpose machine gun, and two Wiltrading Pursuit 640 vessels are carried for boarding operations. The sensor suite consists of a Racal Decca surface search radar operating in the E/F and I bands, and a Wesmar SS 390E dipping sonar. A Bay-class vessel has a crew of 12. The Bay class was built by Austal. The eight ships were delivered over a period of 19 months, beginning in February 1999. The Bay-class design was used as the basis for the 14 larger s in use with the Royal Australian Navy, and the 10 patrol boats used by the Yemen Navy. Operational history The eight patrol boats are operated by the Customs Marine Unit of the Australian Customs Service. They are primarily used to patrol Australia's economic exclusion zone, although they also operate in support of other Australian law enforcement and defence agencies, including but not limited to the Australian Federal Police, the Great Barrier Reef Marine Park Authority, and the Royal Australian Navy. Bay-class vessels often operate on border protection duties under Border Protection Command. The age of the vessels and resulting maintenance needs has seen a drop in the amount of time spent at sea, with other ships of the Customs Marine Unit forced to take up the slack. Foreign service Two Bay-class patrol boats were gifted to the Sri Lankan Navy. Corio