launched on December 1st 1982 and commissioned in 1984. She has a pump jet propulsor in lieu of a propeller and a more compact rudder - features which became standard for the remainder of the class.
SSN 15 HMS Tireless was ordered in 1979, laid down in 1981, launched on March 17th 1984 and commissioned in 1985.
SSN16 HMS Torbay was ordered in 1981, laid down in 1982, launched on March 8th 1985 and commissioned in 1987.
SSN17 HMS Trenchant was ordered in 1983, laid down in 1984, and launched on November 3rd 1986. In 1988, prior to being commissioned in January 1989, she was used to trial the new shiplift and rail transfer arrangements being introduced at
