Project 15470 frigate

Yanaho, c.2010
Class overview
Name:	Project 15470 frigate
Operators:	Itayana Navy
Preceded by:	Project 10705 frigate
Succeeded by:	Project 15490 frigate
In service:	2000-present
Completed:	24
Active:	24
General characteristics
Type:	Frigate
Displacement:	4,900 tonnes
Length:	138.1m
Beam:	14.6m
Draught:	8.6m
Propulsion:	2-shaft COGAG system: As built: 2 x cruise (10,000 kW each) + 2 x boost (27,500 kW each) gas turbines Post-MLU: 2 x cruise (14,000 kW each) + 2 x boost (32,000 kW each) gas turbines
Speed:	+32kn
Range:	4,000 nautical miles at cruise turbines
Boats & landing craft carried:	2 Type 601 cutters or 4-6 RIB boats (post-MLU)
Complement:	193
Sensors and processing systems:	As built: Fregato-M3 3D air search radar Klingo-95 SAM guidance radar Leono-145 fire control radar Post-MLU: Type 2132 3D air search radar Type 3100 SAM guidance / gunnery radar Type 2677 gunnery radar Navigation radar Optronic suite Sonar suite: Hull-mounted sonar Towed array sonar
Armament:	As built: 2 missile mounts (8 missiles) 36 SAM VLS cells 1x1 130mm gun 4x1 76mm guns 4x2 25mm automatic cannons 2x2 533mm torpedo tubes 2 RBU-6000 bomb throwers Post-MLU: 2 missile mounts (8 missiles) 36 SAM VLS cells 1x1 130mm gun 4x1 76mm guns 4 25mm rotary automatic cannons 2x4 324mm torpedo tubes 2 24-barrel multi-purpose launchers
Aircraft carried:	2 helicopters

The Project 15470 also known as the Rainfall-class frigate is a class of frigates in service with the Unifying Navy. Conceived as the primary unit of the Navy in 1990s, the ship was designed with extensive assistance of Redisan and Elatian shipbuilders. The lead ship was commissioned in 2000 and the initial plans to build eight vessels eventually expanded, making the family the mainstay of the Unifying Navy and its most numerous surface combatant through 2000s and 2010s.

General characteristics

The layout of the Project 15470 vessels is characterized by extensive superstructure, several antenna masts, two funnels and a wide helicopter hangar. The hull is 138.1 m long overall, with a beam of 14.6 meters and the draught of 8.6 meters, including a 4-meter bulb housing the bow sonar array. The hull shape was reportedly modeled using computer simulations to optimize hydrodynamic performance.

Ships of the class are powered by the COGAG propulsion system, with two cruise gas turbines and two boost gas turbines powering two reversible screws. The top speed is estimated to be in excess of 32 knots, with reports indicating as high as 36 knots on trials. The operational range of 4,000 nautical miles at economical speed is typical for contemporary frigates. Electrical power is provided by a set of steam generators using heat from cruise turbines, as well as backup diesel generators. The ships carry two 12-meter boats, standard minimum for the blue-water vessels of the Autocracy Navy; vessels after the mid-life upgrade have been known to use 7-meter RIB boats on several occasions. Each ship has a crew of 193, with 11 officers and 37 warrant officers.

The primary offensive weapon of the class is comprised of the two missile mounts amidships that allow variety of missile container launchers to be fitted. Initial ships used exclusively the imported Moskit anti-ship missiles, but at some point around 2008 further launchers were developed for other types of missiles, apparently including the modified Moskit derivative and the Kalibr cruise missile family. For anti-air defence, the ships carry 36 vertical-launch cells in three groups of 12 for various medium and short-range surface-to-air missiles. The exact types of SAMs in service of the Solar Autocracy are unknown, but are likely derived from Rezese, Redisan and Elatian systems.

Contrary to the contemporary naval design trends, ships of the Project 15470 carry an extensive artillery suite. A single dual-purpose 130mm gun is installed fore of the VLS cells, coupled with its own fire control radar and optical targeting module. It is known that the gun itself is licensed from Elatia, and is capable of firing 60 rounds a minute, but not much information is available on its targeting equipment. For close-range air defence, four 76mm guns of the Rezese origin are installed in pairs midships, fore of the missile launchers; those are capable of 120 rounds per minute.

As build, ships were equipped with eight 25mm guns in twin manned powered mounts, two at the fore superstructure behind the fire control radar, and two on top of the hangar. For the anti-submarine warfare, ships of the class carry two twin 533mm torpedo tubes below the main deck fore of the hangar, and two RBU bomb throwers. Two helicopters are housed in the hangar at the stern of the ship, complementing search capabilities and offensive power of the vessel. Those are assumed to be licensed Elatian helicopters, likely modified for compatibility with shipborne systems and datalinks.

The electronic equipment of the class consists of a 3D air search radar, a missile control radar, a gunnery radar, a navigational radar, and an electronic warfare suite mounted below the air search radar. Conceived in 1990s, the ships relied primarily on foreign electronic equipment. Additionally, four optronics stations are mounted at the fore mast. The sonar suite consists of the bow array and the towed array; the exact specifications or the place of origin of those are unknown. The communication tower on the hangar carries the signals complex, including several types of datalinks. The capabilities of the combat integration suite are unknown but are assumed to have evolved over time.

Mid-life upgrade

Starting 2020, the Navy initiated a mid-life refit program for ships of the Project 15470, coded Project 15472. The program serves to addresses the obsolescence of the electronic equipment on the class, dating from the 1980s and 1990s. Ships of the Batch 3 served as a testing ground for various subsystems and equipment.

Externally, the program includes redesigning the funnels and the mainmast of the superstructure to reduce the radar cross section. it is known that the original gas turbines were replaced by a modernized set, offering more power output. The artillery of the class remained the same, although the twin 25mm manned stations were replaced by 3-barrel rotary 25mm guns in remote weapon stations. 533mm torpedo tubes were replaced with quad 324mm torpedo tubes; those are compatible with all standard Navy torpedoes, which eliminated the odd 533mm calibre from the arsenal. Additionally, both RBU bomb throwers were replaced with 24-barrel launchers.

The most important change of the MLU compared to the original design is the complete overhaul of electronics, sensors and support systems. The radar suite was replaced with new radars, and while its overall architecture remained the same, the new radars are of domestic origins. It is known that the change have allowed ships to fire long-range surface-to-air missiles, as was repeatedly observed since 2014. However, no dedicated surface targeting radar was added to complement naval strike capabilities of the class, unlike with the successive projects.

Notable deployments

As the main surface combatant of the Autocracy Navy, Project 15470 frigates have been used to represent the Solar Autocracy whenever and wherever needed, either by themselves or escorting the few capital ships of the Navy. Their first deployments were happened in June 2001, shortly after the first batch was completed on Redisan yards. The ships have been frequently seen on joint exercises with Zacapine, Redisan, Rezese and Elatian navies, as well as representing the Autocracy as far as Velikoslavia, M'Biruna and Elatia.

The success of the design prompted the Solar Temple of Yanbango to massively expand their Star-2 Naval Program, contributing to the expansion of the shipbuilding plants No.75 and No.87. By the time of the Central Karana War, 16 frigates of the first two batches were commissioned, 8 more of the Batch 3 were on varying stages of construction and 24 more were ordered. Their role in the land war was limited to screening territorial waters and the economic zone of the Autocracy, although Yanaho was forced to stay behind due to the engine trouble. The ship was towed to Karana River where it scored two confirmed aircraft kills during the aerial phase of the war.

The 2009-2011 economic downturn impacted the shipbuilding programs of the Autocracy negatively; nevertheless, it appears that all effort was made to finish the frigates already laid down, regardless of the stage of construction. However, no further ships of the class were laid down, and it is known that the Admiralty Staff reordered those ships as more modern Project 15490 frigates rather than outright canceling the orders. The final ships of Project 15470 were commissioned in 2014 and were first officially sighted on manoeuvres with the Redisan Navy in 2015.

It is expected that frigates of the class will remain the mainstay of the Navy until 2030s, by which point they will be supplemented by sufficient number of newer and more advanced designs.

Ships in class

Project 15471, Batch 1

Name	Translation	Shipyard	Laid down	Launched	Commissioned	Status
<name>	Rainfall	Gallentica Naval Works	07.05.1998	25.10.1999	30.10.2000	Active
<name>	<Translation> Rain	Gallentica Naval Works	09.05.1998	27.10.1999	27.12.2000	Active
<name>	<Translation> Rain	Gallentica Naval Works	11.05.1998	29.10.1999	27.12.2000	Active
<name>	<Translation> Rain	Gallentica Naval Works	13.05.1998	31.10.1999	27.12.2000	Active
<name>	<Translation> Rain	Gallentica Naval Works	28.10.1999	15.03.2000	15.05.2001	Active
<name>	<Translation> Rain	Gallentica Naval Works	30.10.1999	17.03.2000	15.05.2001	Active
<name>	<Translation> Rain	Gallentica Naval Works	01.11.1999	19.03.2000	15.05.2001	Active
<name>	<Translation> Rain	Gallentica Naval Works	03.11.1999	21.03.2000	15.05.2001	Active

Project 15471, Batch 2

Name	Translation	Shipyard	Laid down	Launched	Commissioned	Status
<name>	White Cloud	Shipbuilding Plant No.87	05.04.2002	15.09.2004	25.03.2007	Active
Yanaho	Red Cloud	Shipbuilding Plant No.87	06.04.2002	17.09.2004	27.04.2007	Active
<name>	Blue Cloud	Shipbuilding Plant No.87	19.01.2002	25.12.2004	03.07.2007	Active
<name>	Morning Cloud	Shipbuilding Plant No.87	18.02.2002	11.06.2005	21.09.2008	Active
<name>	Evening Cloud	Shipbuilding Plant No.75	23.02.2002	03.08.2004	13.05.2007	Active
<name>	Cirrus Cloud	Shipbuilding Plant No.75	26.03.2002	26.11.2005	04.06.2007	Active
<name>	Cumulus Cloud	Shipbuilding Plant No.75	22.04.2002	30.01.2006	10.08.2008	Active
<name>	Wind-stirred Cloud	Shipbuilding Plant No.75	12.05.2002	30.01.2006	12.10.2008	Active

Project 15471, Batch 3

Name	Translation	Shipyard	Laid down	Launched	Commissioned	Status
<name>	Mountain Cloud	Shipbuilding Plant No.87	01.08.2008	15.09.2011	25.03.2014	Active
<name>	Summit Cloud	Shipbuilding Plant No.87	08.08.2008	20.09.2011	27.04.2014	Active
<name>	Celestial Cloud	Shipbuilding Plant No.87	15.08.2008	25.09.2011	03.07.2014	Active
<name>	Massed Clouds	Shipbuilding Plant No.87	22.08.2008	11.10.2011	21.09.2014	Active
<name>	Rain	Shipbuilding Plant No.75	08.09.2008	03.09.2011	13.05.2014	Active
<name>	Rain	Shipbuilding Plant No.75	15.09.2008	26.09.2011	04.06.2014	Active
<name>	Rain	Shipbuilding Plant No.75	22.09.2008	10.10.2011	10.08.2014	Active
<name>	Rain	Shipbuilding Plant No.75	30.09.2008	24.10.2011	12.10.2014	Active