Àdnachd Class Frigate
Name: Àdnachd Class (Type 31)
Builders: Reinhardt Shipbuilding (original), HDS
Cost Per Unit: $130 million
20 to 40 marines
60 VLS canisters
Inflatable Decoy System
GrandTech MT30 gas turbine
Max. Payload Range
Àdnachd Class Frigate
The Àdnachd Frigate is a multirole frigate produced in Noronica by Hunter Defence Systems. It was designed in the 1980's to be a mainly anti-submarine frigate. However, with its extensive modern redesigns, the frigate is designed for multiple purposes. Despite being nearly two decades old, the Type 31 has received an extensive package of upgrades, making it more than a match for most modern frigate designs.
The Type 31 is one of Noronica's oldest still-active naval vessels, with upgrades meaning that it has been allowed to continue its life on the seas.
The ship is named after the word for 'Adventure' in the Nyssic language.
When first conceived in the late 1970s, the Type 31 was intended to be a light anti-submarine frigate to counter foreign nuclear submarines operating in the Northern Seas. The Type 31 would be replacing the Loch class frigates (which had entered service in the 1960s) and the Fluich class frigate (a general purpose design that recently entered service) as "the backbone of the Noronnican Navy's surface ship anti-submarine force".
The ships were intended to carry a towed array sonar to detect foreign submarines in the Argean and carry a helicopter to attack them. It was initially proposed that the frigates would not mount defensive armament. Instead, missile systems were to be carried by replenishment oilers, one of which was to support typically four Type 31s, though this idea was quickly abandoned.
As a result of lessons learned from monitoring overseas conflicts, the design grew in size and complexity to encompass the Vertical Launch System with an extra tracking system as a defence against low-flying aircraft and sea-skimming anti-ship missiles such as Exocet. With the addition of BITEL surface-to-surface missiles, the Type 31 had evolved into a more complex and balanced vessel optimised for general warfare, which introduced a host of new technologies and concepts to the Noronnican Navy. These included extensive radar cross-section reduction design measures, automation to substantially reduce crew size, a combined diesel-electric and gas (CODLAG) propulsion system providing very quiet running for anti-submarine operations along with excellent range, vertical launch missile technology and a fully distributed combat management system.
It is stated that: "Type 31 frigates achieved approximately 85–95 per cent average availability for operational service in each of the last five years with the exception of 1996 when the figure dropped to just over 80 per cent due to a number of ships experiencing a particular defect. This discounts time spent in planned maintenance."
The Type 31 was designed with modularity and flexibility in mind to enhance versatility across the full range of operations, including maritime security, counter piracy, counter terrorist and humanitarian and disaster relief operations. The adaptable design will facilitate through-life support, ensuring upgrades can easily be undertaken as technology develops. The Àdnachd Class is designed for up to 60 days' endurance and a range of approximately 7,000 nautical miles (13,000 km). Located at the stern are facilities allowing for the deployment of rigid-hulled inflatable boats, unmanned surface vehicles or a towed array sonar. A large Integrated Mission Bay and hangar is located amidship, enabling a variety of missions and associated equipment. Aircraft similar in size to the Boeing Chinook can be flown off the large flight deck, and the hangar can accommodate up to two helicopters the size of a AgustaWestland AW159 Wildcat or AgustaWestland Merlin. The hangar also has space to accommodate Unmanned aerial vehicles.
The Noronnican Navy's version of the Àdnachd class is referred to as the Type 31 frigate. This variant will be equipped with the HDS Clear Skies ASEA Radar and air-defence missiles launched via vertical launching system (VLS) canisters. Additional cells are capable of firing missiles such as the BITEL land-attack cruise missile, a future anti-ship missile, or quad packed AASM missiles. Like its predecessors, the Adventure class will have an acoustically quiet hull for anti-submarine warfare and fitted with a GrandTech Type 2050 Bow Sonar and GrandTech Type 2087 Towed Sonars. Smaller guns include two Excelsior CIWS, four 30mm autocannons and a number of miniguns and general-purpose machine guns.
During the extensive mid-life upgrade, the propulsion system of Noronnican ships will have a gas turbine direct drive and four high-speed diesel generators driving two electric motors in a combined diesel-electric and gas (CODLOG) configuration. Hunter Defence Systems have suggested that some customers will install gas turbine engines and others will prefer to sacrifice 2–3 knots of speed by choosing cheaper diesel engines. The choice of CODLOG configuration for propulsion is somewhat surprising as it is a simpler version of the CODLAG propulsion used on the older versions of the Type 31 – now using an integrated electric propulsion (IEP).
The first steel for the eight Noronnican ships was scheduled to be cut in the summer of 1987. Reinhardt Shipbuilding & Engineering announced the award of the Type 31's first seven equipment manufacturing contracts in July 1985. Contracts were awarded to various companies from Norstham and Noronica for the ship’s air weapons handling system, propulsion gearbox, electric propulsion motor and drive system and testing facility, integrated navigation and bridge system including customer-specific design and development, a land-based integration facility, and a wide range of services. GrandTech Power Engineering was awarded the contract for the gas turbine; whilst Reinhardt retrained the award for the communications systems.