Four Thetis-class ocean patrol vessels have been in service since 1991, and since then have been a key member of the Royal Danish Navy in maintenance of sovereignty, search and rescue, fishery inspection and support to local authorities.
Denmark is located in northwestern Europe. The Vikings founded Denmark more than 1,100 years ago and created Denmark as one of Europe’s oldest kingdoms. Today Denmark is a small nation that occupies most of the Jutland Peninsula and hundreds of islands. Denmark is surrounded by the Baltic Sea and the North Sea.
From this geographical feature of Denmark, the development of this country’s fishery protection and inspection service is an urgent requirement. In the early 1990s, Denmark built a class of large patrol vessels, also called Stanflex 3000, to meet the requirements of the Royal Danish Navy in the new era. The class comprises four ships, the main tasks of this class are maintenance of sovereignty, search and rescue, fishery inspection and support to local authorities.
Based on these tasks and past experience, the ships were built with a displacement of 3500 tons, a length of 112.3m, a beam of 14.4m and a draft of 6m. When completed, the ships can reach an endurance of 8300 nautical miles at varying speeds, consuming no more than 90% of the gas oil available.

By design, the hulls have double-skinned ice-reinforced so that the ships can break through 80 centimetres of solid ice. The propulsion system is a combination of 3 MAN B&W V2R32 diesel engines providing 3943 horse power each. The ships can reach a maximum speed of 22 knots, the seakeeping qualities allow the ships to stand up to wind gusts of 150 knots during light ice conditions and operate in all sea conditions at speeds of 4 to 5 knots.

In order to meet Denmark’s task of defending sovereignty, corresponding weapons were included in the Thetis-class design. The ship’s main armament is a 76mm OTO Melara Super Rapid DP gun. Along with the main gun are two 12.7 mm heavy machine guns and two 7.62mm light machine guns. The fire control system is the Saab Systems 9LV 200 mk3. A FLIR Systems AN/AAQ-22 SAFIRE thermal imaging system is used for surveillance.

Sonar equipment consists of a SaabTech hull-mounted type CTS-36 and a Thales Underwater Systems TMS 2640 Salmon Variable Depth Sonar.