Monday 19 January 2009

A coastal force extends its reach and capabilities.

The Peoples Liberation Army Navy recently introduced two domestically designed and built guided missile destroyers that include Aegis-type radars and related technologies. Known as Project 052C guided missile destroyers (DDGs), the ships feature Aegis-type phased array panels, vertical launch systems, long-range missiles and considerable command and control. These capabilities were not found on any previous Chinese-built DDGs.

The design of a lead ship with prototype Aegis radar, combat direction links and a vertical launch system (VLS) into a small 6,600-ton hull is an ambitious development. The smallest U.S. Navy Aegis ship with VLS is the 8,400-ton Arleigh Burke-class DDG 51. Russia had its Aegis-equivalent Sky Watch system only on 30,000-ton aircraft carriers. The nine years of sea test development prior to the U.S. Navys first installing Aegis on the warship USS Ticonderoga CG 47 indicates the complexity and the engineering effort necessary to build a successful Aegis system. The fact that the Soviet Union gave up on an Aegis system after years of frustrating problems on two warships also shows the extreme difficulties.

China is building only two 052C ships, and the next ship under construction will have a different Aegis and VLS suite. Even so, the mere existence of Peopls Liberation Army Navy (PLAN) warships with long-range phased array radar, communications to other naval assets and over-the-horizon ship-to-ship missiles (SSMs) complicates planning by other naval powers for the Taiwan Straits or other disputed Pacific Ocean waters.

The first sea platform for the U.S. Navy Aegis was the trial ship USS Norton Sound AVM-1 in 1974. The first warship full-up four-panel Aegis system was on the Ticonderoga in 1983, which had 50 meters between the fore and aft deckhouse arrays. The first Aegis destroyer with the single deckhouse array SPY-1D was the 8,400-ton Arleigh Burke lead ship in 1989. More than 50 DDG 51-class ships have been built in this highly successful and constantly upgraded class of warships. All cruiser and destroyer SPY-1 variant antennas are 3.7 meters in diameter and measure 13.5 meters vertically, and they have an F-band frequency of from 3100 to 3500 megahertz.

In 1988, the Soviet Union installed its first Aegis-type Sky Watch on two full-deck aircraft carriers. Each of the four square-plate phased array antennas measured about 5 meters in diameter, and their frequency was estimated to be F-band at about 850 megahertz. This is similar to the Top Plate radar that was mounted on previous Soviet carriers for long-range detection. The port array was 60 meters forward from the starboard array.

The Soviets seem to have had considerable trouble in exercises with their Gorshkov phased array radar, as mechanical scanning Top Sail/Top Pair radars replaced it on the next Soviet carrier, the Tblisi. Sea operations attempting to successfully target incoming threats using external ship or aircraft platforms also seem to have failed.

Chinas first 6,600-ton missile destroyer with an Aegis-type four-plate phased array antenna is the Lanzhou DDG 170 launched in Jiangnan Shipyard in April 2003. The DDG 171 followed six months later. Their undesignated Chinese radar is different from the Aegis or Sky Watch phased array radars. This radar is C-band instead of L- or F-band, and it has convex curved arrays instead of flat panels. The four arrays are 4.6 meters high x 3.9 meters wide, and they face out from the forward deckhouse as on the U.S. DDG 51. China reportedly has purchased two advanced Russian phased array radars for a follow-on larger air defense DDG 103 ship that is under construction at the Dalien shipyard. The short one- or two-ship production runs are a trademark of post-Luda DDG designs.

When the U.S. Navy installed its first MK 41 VLS on the Ticonderoga-class Aegis cruiser CG-52 in 1989, it featured 64 missile cells forward and 32 cells aft. The MK 41 VLS cells launch multiwarfare missiles. The first Russian VLS trials were with SAN-6 missiles on the fourth Kara cruiser in 1977, and the 8,000-ton Udaloy DDG had eight SAN-9 VLS hatches. Both SAN-6 and SAN-9 VLS systems featured round modules with eight cells each and had a large unique Top Dome or Cross Sword acquisition and guidance fire control director and radar/datalink.

The PLAN DDG 170 and 171 feature six HHQ-9 VLS launcher modules forward of the bridge and two aft by the helicopter hanger. At first glance the Chinese VLS launcher looks like the Russian VLS, but there are major differences. The Chinese VLS modules each have two fewer cells than the original Soviet VLS, and the Russian VLS has only one hatch, as eight cells with blow-out patches rotate under it to launch. The rationale that the Russian eight-cell modules were too large for the smaller Chinese DDG hull does not seem valid because the diameter of the Russian module is only 1.5 feet larger than the Chinese module. Possibly, China used S-300 missiles, and Russia provided no naval SAN-6 equipment.

The Chinese VLS has a hinged hatch above each cell and launches each with no rotation needed. China uses a cold launch technique, as does Russia, which eliminates the complex smoke and flame ducts required by the U.S. Navys MK 41 VLS. A PLAN experimental ship has been testing a new VLS that has rectangular hatches similar to the MK 41, and this may be on the next-generation DDG 103 being built in Dalien.

China does not have a large dedicated SAN-6 Top Dome fire control radar near the VLS launchers. The Aegis phased array radar could provide search, and a small antenna near the VLS also could provide X-band acquisition and control links. The smaller guidance and tracking G-/H-band antennas that also have been found on Top Dome radars are located as stand-alone links fore and aft. A small radome is adjacent to fore/aft VLS launcher modules alongside the close-in weapons system, and this is usually covered by canvas in photographs. Several radomes are located fore and aft for satellite communications or non-VLS links or search functions. A very large radome atop the bridge mast may be a Type-364 multipurpose air search, surface search and targeting radar.

The usual PLAN antisubmarine warfare suite would be Italian triple antisubmarine warfare torpedo tubes and 12-barrel Type-75 mortars. Their locations on these new ships are not obvious from initial photographs. Almost certainly a French DUBV-23 bow-mounted sonar dome is under the raked bow. The fully automatic 100-millimeter gun turret on the bow is evolved from the French Creusot-Loire.

A pair of new 30-millimeter seven-barrel close-in weapons systems looks like Dutch Goalkeeper mounts, but the Netherlands claims it did not export the Goalkeeper to China. It appears that China has heavily modified the I-band Goalkeeper antenna, which also appeared on prior Project 052B DDGs. The Chinese designation for this close-in weapons system is Type-730.

A Luda upgrade first installed rectangular YJ-81 SSMs in 1999, and this has continued through the YJ-81s on new DDGs. The large Russian Bandstand radome supports SSMs with a 250-kilometer-range I-band active radar and a 450-kilometer-range multiband passive radar. Chinas DDG 107 has six new round-tube-shaped SSM launchers of slightly larger diameter than earlier C-803 SSMs. This indicates a more modern, longer range version of the C-805 (YJ-85) or a newer Russian supersonic SSM.

Taking full advantage of Aegis requires effective datalinks. The concept for the Naval Tactical Data System (NTDS) was outlined in a NATO study in 1955. Three NATO ships were the testbeds for prototype NTDS in 1961, and they operated together for years of development trials. Link 11, also called TADIL-A, was a high frequency (HF) and ultrahigh frequency (UHF) digital encrypted data bus. Later, wideband Link 16 UHF with 10 times the speed was added with antijam frequency hopping included.

Soviet NTDS concepts, such as integrated communication links, first appeared on Kara and Kresta II. The Bell Crown system, which was replaced by the newer Bell Thumb in 1993, was the original Soviet Link 11. The Light Bulb antenna serves the Link-16 Joint Tactical Information Display System (JTIDS) role, which would be replaced by newer AT-2M for Link-16 traffic. Russia has the expected surface-ship-to-aircraft and missile guidance datalinks. Light Bulb and Bandstand were datalinks to the SS-N-22 SSM on PLAN Sovremenny-class ships purchased from Russia.

The first Chinese tactical communication links with characteristics similar to NTDS were observed on the 4,200-ton Luhu-class DDGs in 1991. Initial TAVITAC CDS installations took place on the DDG 105 in 1987, and other Luda models in 1987 could have tried the concept. The PLAN link frequencies of 225 megahertz HF and 400 megahertz UHF are the same frequencies NTDS uses and may be part of the Chinese tactical datalink system designated HN-900.

Western vendors have provided Chinese aircraft with the MIL-STD 1553B data bus, which now has been installed on new 052 DDGs. China has used a Type-W datalink provided by France to non-NATO export customers that is similar to TADIL-A. Sovremenny and Ka-25 helicopters are equipped with the A-346Z secure datalink in addition to HF, very high frequency (VHF) and UHF radios. The newest frigates and DDGs 168, 169 and 170 have the HN-900. The HN-900 probably includes some of these foreign datalink technologies. The Russian Light Bulb datalink is positioned above the DDG 170 helicopter hanger, and Bandstand provides coordinated operations between the Russian navy using Chinese datalinks.

A Soviet 1950-vintage A-band Knife Rest early warning yagi radar antenna is aft. This antenna was not on 052B or the Luhu, but it was on the Luhai and 1990-vintage Luda upgrades and Jiangwei frigates. This seems to hint a weakness in the Aegis, which normally should perform such detection.

The Chinese Aegis DDGs have their own Ka-25 helicopters that can have distant reconnaissance or targeting capabilities and possibly can even carry missiles, although the Aegis concept is to pass target data to the control ship that would launch its weapons. Long-range shore-based fighter aircraft such as the Su-30MKK with its M400 over-the-horizon multispectral reconnaissance pod can pass target data back or can even be vectored to attack with its own long-range 3M80 Moskit missiles by the control ship. The early Su-27SK had an analog voice-encoding link, but the newer Su-30MKK has a TKS-22 datalink. China is negotiating with Russia to equip future Su-30 MK2 aircraft to include the next-generation TSIMSS-1 digital datalink. The DDG 107 would need the appropriate Sukhoi-variant link.

Long-range maritime patrol aircraft (MPA) variants of Tu-154- or Y8-converted An-12 are excellent reconnaissance assets with direct links to the Aegis control ship. Soviet naval MPA used R-837 and R-807 for long-range communications, and the R-802 was the UHF command radio—all of which are on PLAN ships. China has limited ocean reconnaissance satellite capability, but it is known to intercept and utilize data from other nations’ satellites, including those of the United States. Other non-Aegis warships can be good over-the-horizon data sources as long as they have the appropriate datalinks. They could even be shooters if targets are within their missile range. Naturally, the Sovremminy, the Luhu and the Luhai are the best consorts, but other frigates or Luda destroyers also could be used if necessary.

A key element required for an integrated Aegis capability is a shipboard local area network (LAN) and common display consoles shared by a sensors and computer/control station. The U.S. Navy has had several generations of workstations on its Aegis ships.

Soviet ships had primary Second Admiral force command consoles and subordinate Second Captain own-ship warfare area consoles. These were used on large Soviet cruisers such as the Slava and the Kirov prior to the appearance of Sky Watch.

Chinese combat system architecture is less visible, and open literature sources do not directly describe it. A photograph in a working space on the Luhu showed several identical consoles being manned by technicians, and this was not seen on earlier stovepipe sensor and weapon equipment. The consoles do not look like any units seen on Soviet or French products, and they may have been designed and produced by Chinese electronic plants. Possible vendors are the Jiangsu Automation Research Institute, which is known to make rugged naval computers and displays, and Huanwei Technology, which makes Ethernet switches, routers and fiber optic datalinks.

As on the U.S. Aegis ships, such systems can retain many of the original hardware cabinets, but the unique display console might be replaced with a standard shared console including open architecture LAN access. Chinas choice of a LAN could be a Russian GOST standard or a Digibus LAN used on French TAVITAC CDS aboard recent PLAN ships. Ethernet or MIL-STD 1553 already are used in avionic and army systems and easily adapt to naval equipment, which supports interoperability of forces. Display console software operating systems likely would be commercial standard versions such as Windows or VX Works that are in production in China.

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