Type 23 frigate

The Type 23 frigate, also called the Duke class, is a class of sixteen frigates built for the United Kingdom's Royal Navy and named after British dukes. Conceived in the late 1970s as a light anti-submarine ship with a towed array sonar, it grew after the Falklands War into a general purpose warship carrying the vertically launched Sea Wolf missile. The Royal Corps of Naval Constructors designed it with Yarrow Shipbuilders as prime contractor, and it introduced radar cross section reduction, automation that cut crew size and a combined diesel-electric and gas propulsion system for quiet running. The first ship, HMS Norfolk, was commissioned in 1989 and the last, HMS St Albans, in 2002. Three went to the Chilean Navy, several have retired since 2021, and Type 26 and Type 31 frigates are replacing the rest.