Type 730 CIWS

The Type 730 is a Chinese seven-barrelled 30 mm Gatling gun CIWS. It has a PLA-N designation H/PJ12. It is mounted in an enclosed automatic turret and directed by radar, and electro-optical tracking systems. The maximum rate of fire is 5800 rd/m, and the effective range is up to 3 km.

Origin
The system's primary purpose is defence against anti-ship missiles, and other precision guided weapons. However, it can also be employed against fixed/rotary wing aircraft, ships and other small craft, coastal targets, and floating mines. Though externally similar to the Dutch Goalkeeper in appearance, it is thought to operate indigenous radar and optical systems. Another reported source of technology was reported to be the French which had experimented with the same General Electric EX-83 mount for their CIWS requirements. Two systems, SAGEM's SAMOS and the Thomson-CSF's SATAN were under evaluation in October 1987. The SAGEM SAMOS system featured the EX-83 mount with a SAGEM VOLCAN optical director, while the Thomson-CSF variant was controlled with an off-board Castor IIJ fire-control radar. Photos of the prototype Type 730 unit under trial apparently shows a SAGEM VOLCAN EO director in place of the domestic OFC-3 EO director.

Development
The gun is designed by the 713th (research) institute under the name 'Project 850' and is powered by two electric motors. The radar TR47C is a derivative of the EFR-1/LR66 J-band radar (NATO code name: Rice Lamp) by Xi'an Research Institute of Navigation Technology, but it is unclear that if this derivative is developed by the same institution. The OFC (Optical Fire Control)-3 electro-optical fire control system is designed by the Central China Optronic (electro-optical) Research Institute.

Radar
The TR47C radar operates in the same way of AN/APY-1/2 radar onboard E-3 Sentry in that the azimuth is scanned mechanically, while the elevation is scanned electronically, incorporating a total of 169 transceivers of phased array technology that enables the radar to pick up the splashes of 30 mm rounds. Like the western CIWS, the information is processed on site, via local computers of the radar and the gun mount, thus providing faster reaction time than the Russian design in which the radar and fire control system are separately located.

Electro-optics (optronics)
The OFC-3 system is modular design that comprises a laser range finder, a color TV camera, and an IR camera, and the laser range finder can be replaced by a laser designator (for a laser beam-riding SAM), the TV camera can be replaced by a night vision camera, and the IR camera can be replaced by an ImIR, at higher cost. Development to incorporate the dual band IR, night vision camera, and the color TV camera is reportedly in progress.

Fire-control system
Like western CIWS, Type 730 CIWS is an autonomous closed-loop system and thus offers faster reaction time than the Russian AK-630. Type 730 CIWS is fully compatible with Chinese and European combat data systems such as ZKJ-1, ZKJ-4, ZKJ-4A-3, ZKJ-5, ZKJ-6, ZKJ-7, H/ZBJ-1, and Thomson-CSF TAVITAC, and can be directly integrated with these combat data systems without any modification.

Range
The system can track a sea-skimming target with 0.1 square metre radar cross section at 8 km, extended to 15 km if the radar cross section is increased to 2 square metres, and further extended to 20 km if the radar cross section is increased to 10 square metres, though the targets could not be engaged until much closer (3 km) due to the limited range of the gun.

Gun
The 30 mm Gatling gun mount designated as H/PJ-12 is extremely similar to the General Electric GAU-8/A Avenger. Although there are sources claiming that it is the Chinese version of the Russian Gryazev-Shipunov GSh-6-30 Gatling gun, this appears to be unlikely, since the Russian Gatling gun only has six barrels. H/PJ-12 is versatile in that its FCS system can be either separately installed at different locations like the Soviet AK-630, or directly integrated on the gun mount like most western equivalents. Like the American GAU-8/A Avenger, it is recommended not to fire longer than a single minute at a rate of 4,200 rounds per minute, after which the generated heat would begin melting the rifles of the barrel, shortening its useful life. Rates of fire beyond 4,200 rounds per minutes increase wear. There are two ammunition drums each contains 250 rounds, and other versions of the ammunition drums have been reportedly developed.

LD-2000
The Chinese are currently developing a new version of the system which will include missiles on the same installation. A land based variant designated LD-2000 (LD: Lu Dun, 陆盾, meaning Land Shield) have also been successfully developed, but this land version lacks the electro-optic fire control system of the ship-borne version, instead, the radar is supplemented by a thermal imaging sight. The weapon is loaded with 1,000 rounds, enough, apparently, for about 48 potential target engagements, same as its naval counterpart, with effective range of 2.5 to 3.5 km. However, the missile armed version was first successfully developed for the land based version as LD-2000 Gai, with six surface-to-air missiles, three on each side of the turret, as it was revealed to public in 2005, but it is not clear the exact type of the missile, some claim that they are TY-90, while others claim they are DK-9, the surface-to-air version of PL-9.

Deployment
The system has been fitted on board the Type 052 (after 2011 refit), Type 052B, Type 052C, Type 052D, Type 051C destroyers, and the F-22P and Type 054A frigates so far, and may replace some Type 76 mounts on older combatants.

Type 1130
Further development of Type 730 results in Type 1130, which first appeared on Chinese aircraft carrier Liaoning. This successor of Type 730 is also 30 mm caliber and has a total 11 barrels, with reported rate of fire of 9,000 to 11000 rounds per minute Originally developed with 10 barrels, it eventually had 11 barrels when completed, and rumored to have the nickname Vulcan. Although it's reported that FL-3000 missiles can be integrated to the gun like FCS, this has not occurred yet, and FL-3000 was installed separately on the first Chinese aircraft carrier in its own launchers.