The Iver Huitfeldt class is a three-ship class of frigates that entered service with the Royal Danish Navy in 2012 and 2013. The class is built on the experience gained from the Absalon-class support ships, and by reusing the basic hull design of the Absalon class the Royal Danish Navy have been able to construct the Iver Huitfeldt class considerably cheaper than comparable ships. The frigates are compatible with the Danish Navy’s StanFlex modular mission payload system used in the Absalons, and are designed with slots for six modules. Each of the four stanflex positions on the missile deck is able to accommodate either the Mark 41 8-cell Harpoon launcher module, or the 12-cell Mark 56 ESSM VLS. The Peter Willemoes passed the British Flag Officer Sea Training test in 2015. While the Absalon-class ships are primarily designed for command and support roles, with a large ro-ro deck, the three new Iver Huitfeldt-class frigates will be equipped for an air defence role with Standard Missiles, and the potential to use Tomahawk cruise missiles, a first for the Danish Navy. The ships were constructed in blocks in Estonia and Lithuania. These blocks were then towed to Odense where they were assembled.
Most of the weapons for the three ships were reused from the previous Niels Juel-class corvette and the Flyvefisken-class patrol vessel. Other components were reused as well to keep the cost at a minimum. These ships share their Anti-Air Warfare suite with the Royal Netherlands Navy’s De Zeven Provinciën-class frigates and the German Navy’s Sachsen-class frigates. The sensors of this suite include the long range surveillance radar SMART-L (passive electronically scanned array) and the multi-function radar APAR active electronically scanned array. The SMART-L and APAR are highly complementary, in the sense that SMART-L is a L band radar providing very long range surveillance while APAR is an I band radar providing precise target tracking, a highly capable horizon search capability, and missile guidance using the Interrupted Continuous Wave Illumination (ICWI) technique, thus allowing guidance of 32 semi-active radar homing missiles in flight simultaneously, including 16 in the terminal guidance phase. The primary anti-air weapons are the point defence Evolved Sea Sparrow Missile and the area defence SM-2 IIIA. The Mk 41 Vertical Launch System is used to house and launch these missiles. Depending on the number of Harpoon launchers installed, up to 48 Evolved Sea Sparrow Missile and 32 SM-2 IIIA may be carried.
The seven-deck monohull design features 15 watertight sections. It has been designed to reduce radar signature, infrared radiation, underwater noise and magnetic signature to make the ship as invisible as possible to an enemy. The exterior is easily distinguished from Absalon Class as the Iver Huitfeldt is one deck lower, and lacks an internal multipurpose deck (flex deck). The chimney’s design has been changed to prevent excessive steam impact of SMART-L radar. The design protects the crew from contamination. The frigate is divided into six hazard zones. All the zones are equipped with separate filters to protect the crew against chemical, radioactive or biological weapon attacks and airlocks are provided between them.The frigate is powered by four main MTU 20V 8000 M70 diesel engines, placed two and two each, in a combined diesel and diesel configuration. The propulsion system provides speeds more than 28k. The ship is equipped with two Becker rudders and a bow thruster with an output of 900kW. A set of active stabilisers provides stability to the frigate. Four generating sets comprising two Caterpillar engines and Leroy-Somer generators are provided. Each pair includes a CAT3512 and CAT3508 generating 1,360kW and 920kW respectively.
The builder’s successor, OMT, suggests the type for the Procurement programme of the Royal Australian Navy’s frigates, but built in Australia and modified for anti-submarine warfare. (along with the RNZN as they have a preference to operate the same type of frigate as the RAN). However OMT was not among the three warship designers shortlisted by Australia for the SEA 5000 frigate program in April 2016. The Iver Huitfeldt class frigate was a contender in the Canadian Single Class Surface Combatant Project. However, it is believed that due to concerns over the fairness of the bidding process, two European shipbuilders, possibly Germany’s ThyssenKrupp Marine Systems and Odense Maritime Technology, declined to submit bids. In late May 2018, Babcock , partnered with BMT and Thales Group, announced the “Arrowhead 140” design, based on the hull of the Iver Huitfeldt frigates, for the Royal Navy Type 31e frigate program.