COLUMN | Seabed warfare emerges from the shadows [Naval Gazing]

A 1.2 million-kilometre international network of seabed cables conveys electricity gas, water, and about 97 per cent of all voice and internet traffic around the world. These cables have a significant military role, in part because they are markedly less exposed to interception of sensitive data than are surface transmissions.

Military aspects

However, much of the vital network is situated in fairly shallow water and is therefore vulnerable to attack from hostile subsea and surface vessels. With the exception of Russia, which has a large inventory of undersea and surface craft fitted with specialist kit (such as tracked submersibles and underwater grapples, all capable of both attacking and defending seabed installations) most nation’s maritime security forces currently have very limited capability to counter this threat.

Incidentally, many Russian seabed operations vessels come under the command of the specialist (and politically powerful) General Staff Main Directorate for Deep Sea Research, rather than the Russian Navy.

For its part, China's huge People's Liberation Army Navy (PLA-N) has a large fleet of intelligence gathering auxiliaries, but historically, this fleet has been largely focused on the activities of western surface warfare assets, particularly missile firings.

Beijing seems to be shifting its emphasis though, as according to some reports, the PLA-N has recently cut a cable linking the island of Taiwan with Taipei-claimed Matsu, an outpost that is located very near to the Chinese mainland.

Awareness of this little-publicised threat was further boosted in late November, when reports emerged of two cables beneath the Baltic Sea having been severed simultaneously. These cables, which reportedly carry mainly data traffic, serve Sweden, Germany, Finland, and Lithuania.

Investigations into the incident continue, with both the Swedish and German governments publicly pointing fingers at the Chinese merchant vessel Yi Peng 3, which is known to have been operating in the area.

Investigation in progress

The Swedes and the Germans are currently promulgating that the Chinese ship had deliberately, or accidentally, dragged its anchor over the cables. The Chinese vessel meanwhile remains in the area under the guard of a pair of Royal Danish Navy warships.

There have been reports that damage to the ship’s anchor is visible. In practice, though, investigations into incidents of this sort are mainly for political and security reasons and rarely result in any publicly acknowledged definitive conclusions.

Why might Beijing have targeted these cables? Firstly, analysts believe that it is very likely that they are heavily used to carry military communications traffic, but some regional commentators suspect that persistent unfavourable regional diplomatic and media coverage of Chinese diplomatic and security matters might have prompted Beijing to send a subtle warning.

A number of western naval units, including the UK Royal Navy’s new Astute-class nuclear-powered attack submarines, have some limited seabed warfare capability, while dedicated seabed warfare assets currently available to western navies to carry out such operations include the new UK multi-role ocean surveillance ship (a converted offshore supply vessel) Proteus and the US Navy’s modified Seawolf-class attack submarine Jimmy Carter.

The Americans, however, are currently constructing an advanced derivative of the Virginia-class submarine to add to its specialist seabed warfare flotilla.

Seabed operations vessels rely very heavily upon a range of crewed and uncrewed submersible craft, many of a highly classified nature, in order to carry out their role. The capabilities of Proteus, which flies the blue ensign of the Royal Fleet Auxiliary, includes three large Kongsberg Hugin uncrewed underwater vehicles supported by a hangar and port and starboard launching systems, a multibeam echosounder, and a helicopter flight deck.

There is little doubt that seabed warfare is at last emerging from the shadows, and is set to become a progressively important element of national defence commitments.