Nanjia-class frigate

The Nanjia-class frigate (Guoyu: 南贾级型导弹护卫舰; Nán jiǎ jí xíng dǎodàn hùwèijiàn) is a class of multi-role guided missile frigates built by the Jiaxing Shipyard for the Imperial Kodeshi Navy (IKN). They entered service in 1994 and are currently the largest surface frigate within the IKN. The name "Nanjia" refers to the small city of the same name. The ships were designed with a modular design that allows them to be upgraded as technology advances. In addition to their main armament, they also carry a variety of smaller weapons such as anti-submarine torpedoes, depth charges, mines, and missiles. Each ship can deploy one medium helicopter and a drone, which are used primarily for search and rescue operations, anti-submarine warfare, and intelligence gathering missions.

Background
The Nanjia-class was originally intended to replace the older Chengnan-class (城南) frigates, but due to budget constraints, only two were constructed instead of the planned three. As a result, the IKN had to rely on its Chengna-class fleet for over a decade until the construction of the first Nanjia-class was completed. This led to the IKN having a large number of obsolete vessels, many of which were decommissioned and scrapped. These included the decommissioned Chengnan-class frigates, the decommissioned Zhaojian-class frigates, and the decommissioned Heilongjiang-class frigates.

The Nanjia-class is a multi-role guided-missile frigate designed by the Jiaxing Shipyard. It is based on the hulls of the decommissioned Heilongjiang-class frigates. The new hulls were modified to accommodate modern weapons systems and improved stealth capabilities. The ships have a displacement of 4,055 tons at full load and a length of 122 metres. The ships have a beam of 17.7 metres and a draught of 12 metres. The ships are powered by a pair of gas turbines that drive four-shaft generators. The turbines provide the power to run the ship's electric motors which propel the ship through water. The engines can achieve speeds up to 30 knots.

Each ship carries a flight deck capable of handling one medium helicopter and a drone. The helicopter is used primarily for search and rescue operations, anti-submarine warfare, and intelligence gathering missions. The drone is mainly used for reconnaissance and surveillance missions. The helicopters are fitted with a pair of fixed landing pads. The drones are fitted with a retractable skid and a pair of wheels. The ships' hangar is equipped with a pair of cranes that can lift the aircraft from the flight deck. The hangar has room for one medium helicopter and a drone.

Design
The ships are powered by a pair of gas turbines that drive four-shaft generators. The turbines are fed by a diesel generator. The diesel generator provides the power to operate the ship's electrical motors. The motors are used to move the ship through water. The motors can reach speeds of 30 knots. The ships are propelled by a combined diesel and diesel (CODAD) propulsion system. The CODAD system consists of two diesel generators and two gas turbine engines. The gas turbine engines power the ship's main and auxiliary drives while the diesel generators provide power for the ship's electrical systems. The CODAD system reduces the amount of exhaust gases produced by the ship and allows for the use of smaller engines. The ships are equipped with KONSAI K-33J/DSZL multi-function Active electronically scanned array radar, S-band, and an AN/SPS-49(V)11 surface search radar. The radar is able to detect targets out to a range of 300 nautical miles. The radar is able to track multiple targets simultaneously. The radar is connected to a computerised fire control system that enables the ship to target and destroy enemy vessels. The system is able to identify targets using active or passive sensors. The ships are equipped with a Kingklip Mark 1115 hull sonar. The sonar is mounted on bow of the hull. The sonar is able to detect submarines, surface ships, and aircraft. The sonar is also equipped with a passive acoustic system. The system is able to detect the sound of submarine propellers. The ships carry a pair of 20 mm remotely operated guns. The guns are used for self-defence purposes. The guns are controlled by a computerised fire control system. The guns can be elevated to +15 degrees and depressed to -5 degrees. The guns are fitted with a laser range finder, infrared sensor, and a thermal imager. The ships are equipped a helicopter and a drone. The helicopter is used primarily for search and rescue operations, anti-submarine warfare and intelligence gathering missions. The drone is mainly used for reconnaissance and surveillance missions. The drone is fitted with a retractable skid and a pair of wheels. The ships' hangar is equipped with a pair of cranes that can lift the aircraft from the flight deck. The hangar has room for one medium helicopter and a drone.

Description
The ships of the Nanjia class were built by Jiaxing Shipyard in Shanghai. The hulls were modified to accommodate modern weapons systems and improved stealth capabilities. The ships have a displacement of 4,055 tons at full load and a length of 122 metres. The ships have a beam of 17.7 metres and a draught of 12 metres. The ships are powered by a pair of gas turbines that drive four-shaft generators. The turbines provide the power to run the ship's electric motors which propel the ship through water. The first ship of the class was laid down in 1990 and was completed in 1994. It undertook sea trials in 1995. Before it was finally commissioned into the IKN, the ship underwent further modifications. These included the installation of new sonar equipment, radar systems, and missile launchers. The second ship was launched in 1996 and completed in 1997. Both ships were commissioned into the IKN in 1998.

Propulsion
The ships are propelled by a pair of gas turbines that drive four-shaft generators. The turbines are fed by a diesel generator. The diesel generator provides the power to operate the ship's electrical systems. The turbines are able to reach speeds of 27 knots. The ships are propelled by a combined diesel and diesel (CODAD) propulsion system. The CODAD system consists of two diesel generators and two gas turbine engines. The gas turbine engines power the ship's main and auxiliary drives while the diesel generators provide power for the ship's electrical systems. The CODAD system reduces the amount of exhaust gases produced by the ship and allows for the use of smaller engines.

Armament
The main gun is a 100 mm naval gun mounted in a cupola. The gun is able to fire at a rate of 6–10 rounds per minute. Each gun is able to engage targets out to a range of 10 kilometres. The guns are controlled by a computerised fire control system. The gun mounts are protected by a pair of armoured bulkheads. Additionally, two 30 mm remote-operated guns are installed amidships. The ship carries eight anti-ship missiles for anti-ship operations. While two sets of 48-cell VLS are carried for surface-to-air missiles.

Fire control and sensors
The radar is a KONSAI K-33J/DSZL multi-function Active electronically scanned array radar, S-band. The radar is able to detect targets out to a range of 300 nautical miles. The radar is able to track multiple targets simultaneously. The radar is connected to a computerised fire control system that enables the ship to target and destroy enemy vessels. The radar can identify targets using active or passive sensors. The radar is connected to a computerised fire control system that enables the ship to target and destroy enemy vessels. The ship is armed with a 100mm naval gun, mounted in a cupola. The guns are able to fire at a rate of 60 rounds per minute. Each gun is able to engage targets out to a range of 18 kilometres. The guns are controlled by a computerised fire control system. The gun mounts are protected by a pair of armoured bulkheads.

Aircraft
The ships are equipped with a Zhongbin Z.31 medium helicopters and a KONSAI WZ.5 or Nanbin W.54 drone. The helicopter is used primarily for search and rescue operations, anti-submarine warfare, and intelligence gathering missions. The drone is mainly used for reconnaissance and surveillance missions. The ships' hangar is equipped with a pair of cranes that can lift the aircraft from the flight deck. The hangar has room for one medium helicopter and a drone.

Ships in class
A total of 15 ships are planned to be built. The first four ships were built by the Jiaxing Shipyard in Chenghai.

Construction and service
The Nanjia-class is the first major class of Kodeshi-designed warships to be built using integrated modular construction. The hulls were designed by the IKN's Naval Architecture Department. They were constructed by the Jiaxing Shipyard in Chenghai, which is one of the nations leading naval shipyards. The hulls built using this method are made up of a number of modules, which are welded together to form a single hull. This process should reduce costs and construction time compared to traditional methods. The steel-cutting ceremony took place on 20 July 1991, with the keel laying taking place on 28 March 1991. The first ship the Nanjia was launched in December 1993 and was commissioned into the IKN in November 1994. The second ship in the class was launched in June 1996 and was commissioned in October 1997. The third ship in the class was launched in February 1998 and was commissioned in April 1999. The Imperial Kodeshi Navy plans to have all 12 ships in active service by 2025.

Export
The frigate design has been showcased at a number of international defence exhibitions. It has attracted considerable interest from foreign navies and has led to a number of export deals. The frigate design was entered into Mervaria's Next Surface Combatant Tender.