THE West has some formidable missiles designed to sink warships.
Three of the most deadly are America's Harpoon, France's Exocet and the
Swedish RBS-15. These all fly close to the speed of sound for up to
about 200km (124 miles) using precision-guidance systems to skim over
land or water. This makes them difficult to detect. And even if they are
spotted, the missiles can fly in unpredictable patterns, which makes it
harder to shoot them down. They then punch a warhead, weighing as much
as 200kg (440lbs), into a moving ship with devastating consequences.
Despite all this, missile defences can be effective. Shooting at
missiles with rapid-firing guns, or anti-missile missiles, can bring
them down. The incoming missile's electronics can also be scrambled with
blasts of electromagnetic radiation, such as microwaves. And decoys can
be fired to trick the missile's homing sensors and lure it away from
the vessel under attack. But missile attacks on ships are rare, so it is
difficult to know just how safe a ship really is—especially if an
attacker launches a dozen or so missiles at once.
One particular anti-ship missile has become especially worrying for
Western defence chiefs. This is because it is even more fearsome than
anything NATO countries and their allies now use. The Russian-made
missile is called the Club and it can carry bigger warheads farther than
any anti-ship missile the West can launch.As is the way of NATO nomenclature, the Club has been designated
another name, the Sizzler. In some configurations the Sizzler can
deliver about 450kg of explosives as far as 300km. It also carries out
defensive manoeuvres—even curving around islands—and some lighter
versions perform a unique, nasty trick: the warhead separates a few
dozen kilometres away and then accelerates from almost the speed of
sound to about three times as fast.
Sizzling targets
Tim Keating, an American vice-admiral, told the House Armed Services
Committee early last year that America's ability to defeat the Sizzler
was uncertain, not least because the military lacked an adequate dummy
stand-in for testing defensive systems against such a fast missile. Now
one is in the works. Dan McNamara, a manager with the US Navy group
developing what is called the Multi-Stage Supersonic Target, says it
will help defeat the “groundbreaking” Sizzler. The new missile is
expected to be ready in 2014.
The Sizzler is the leading example of a growing class of supersonic
cruise missiles designed by non-Western countries. Versions of it, and
its competitors, can be launched from submarines, aircraft and vehicles.
The Yakhont, a slightly slower Russian missile that also carries a
heavy warhead, has been sold to countries including Indonesia and
Vietnam. The BrahMos, a joint Indian and Russian upgrade of the Yakhont,
comes even closer to matching the Sizzler's effectiveness.
These non-Western supersonic missiles are changing defence thinking.
To begin with, uncertainty about ship “survivability” is increasing as
missiles proliferate, says Steve Zaloga, a missile expert at Teal Group,
an aerospace consultancy in Fairfax, Virginia. China and India already
have Sizzlers and countries that have indicated interest in, or bought,
the Sizzler or versions of it include Algeria, Syria, the United Arab
Emirates and Vietnam. Some think Iran probably has Sizzlers too.
As a rule of thumb, to hit a well-defended modern warship a volley of
more than ten subsonic missiles might be needed, according to an expert
at Thales, a French defence contractor. How much deadlier might
supersonic ones be? Sinking a warship, especially a big one, is unlikely
with a single missile, whether supersonic or not. More probably,
attackers would score a “mission kill” that limits a ship's ability to
fight. In 2006 a subsonic missile fired by Lebanon's Hizbullah militia
seriously damaged an Israeli corvette more than 15km offshore. Four
sailors were killed.
Hizbullah's success highlights the so-called “asymmetric” element of
anti-ship technologies: striking a warship can be far less expensive and
complex than operating and defending one. According to Rafael, an
Israeli defence contractor, a ship's protection gear often costs as much
as its attack weaponry. Missiles are now the “poor man's way” of
obtaining sea power, says Nathan Hughes, an analyst at STRATFOR, a
consultancy in Austin, Texas.
Iran is one country gaining naval power without much in the way of
sophisticated ships. It has large numbers of anti-ship missiles which
can be launched from small, fast boats or batteries hidden ashore in
buildings or trucks. Defence officials are troubled by the prospect of
missiles that can be launched from civilian positions. A product
designed by Concern Morinformsystem-AGAT, the Russian company behind the
Sizzler, may heighten such fears. The firm now offers a four-missile
launching package hidden inside a standard commercial shipping
container. It could be transported on a ship, train or big lorry. Called
the Club-K Container Missile System, it provides dangerous potential to
rogue forces, says a Western arms-market consultant who has visited the
manufacturer's facilities in Russia.
Defensive technologies, of course, will also improve. Sofradir, a
French remote-sensing defence contractor, plans to start making a
“multichannel” missile-detection system later this year. (Early versions
are already being tested by potential customers.) It integrates radar,
infra-red and visible-light sensors into a single unit. Software can
then better assess the quality of data from one channel by comparing it
with data from the other two. Such sensing technology should make it
easier to “lock onto” (and therefore shoot down) incoming supersonic
missiles, especially when they tend to gain altitude to pinpoint a
target before dropping down for a final sea-skimming approach, says
Philippe Bensussan, Sofradir's chief executive.
From the deep
But there are also threats from below to deal with. The sinking in
March of a South Korean frigate provides a further example of the
asymmetric nature of anti-ship weapons: the evidence suggests that it
was sunk by a torpedo fired from a North Korean “midget submarine” small
enough to hide in shallow water, where it is hard to detect using
sonar. North Korea is thought to have supplied such submarines to Iran.
Torpedoes can still be tricked, in many cases, with decoys that emit
sound waves to mimic ships. But torpedoes, like missiles, are getting
smarter. Their homing and guidance systems are improving. Many
torpedoes, once fired, can be controlled via a long optical fibre that
remains attached to the submarine to increase accuracy and prevent
jamming. And some torpedoes will now circle back if they miss a target
on the first pass. At Rafael, the Israeli defence contractor (and a
maker of anti-torpedo countermeasures), a spokesman reckons that torpedo
effectiveness has roughly doubled in the past decade, also in part
because of work carried out in Russia.
Torpedoes rarely travel faster than 100kph because water friction and
turbulence could cause them to veer off course or suffer damage. But
now speeds can be doubled or even tripled by “cavitating” torpedoes. The
trick involves positioning a flat disk, smaller than a DVD, about 10cm
in front of the torpedo's nose tip. At high speed the disc vaporises
water, creating a steamy air bubble, called a cavity, which envelops the
torpedo. This dramatically reduces water drag.
Cavitating torpedoes remain rare, not least because they are
problematic. High speeds can make it hard to decipher the sonar signals
used for guidance. Propulsion is provided by a rocket engine, rather
than a propeller and rudder, which makes steering difficult: some
cavitating torpedoes can travel only in a straight line. High pressures
deep underwater pose further difficulties, and may have contributed to
the sinking of Russia's Kursk submarine in 2000, killing all on
board. (It sank after an explosion during the testing of a cavitating
torpedo called Shkval, or Squall.) A German cavitating torpedo called
the Barracuda is thought to be the fastest, but Russia's Shkval is sold
more widely.
As ship vulnerability increases navies are buying more submarines,
especially in Asia, says Ramli Nik, Malaysia's defence attaché to the
United Nations until 2004. Malaysia will receive its second attack
submarine by the end of the year, he says. Other countries plan to buy
or build more. Australia expects to double its fleet of six; Indonesia
aims to expand its fleet from two to 12 and Singapore expects to double
its fleet of four. Vietnam has none but plans to have six by 2025. By
then, China may have 70 attack submarines. Mr Nik thinks submarines
provide the best naval defence platform. With modern remote-sensing kit,
they can stealthily “get all the details” of warships, he adds.
Yet warship-building is far from declining. Naval budgets, broadly
speaking, are growing because of a big shift in strategy caused in part
by improved missile capabilities. Premvir Das, a former commander of
India's Eastern Naval Command, says the availability of fast, powerful
and accurate cruise missiles is encouraging forces to restructure so
that they are better able to conduct, or support, land warfare from the
sea. India, he says, will extend the range of its BrahMos missile “quite
substantially” beyond its current 300km range.
Even more exotic new weapons could be just over the horizon. About
five years ago Pentagon officials learned that Chinese engineers working
on a government missile project appeared to have solved a difficult
technical challenge involving manoeuvring with radar data. According to
Eric McVadon, a retired American rear-admiral, some of his fellow
defence officials began “running around with their hair on fire”. China
was modifying a medium-range space-faring ballistic missile, the DF-21,
so it could re-enter the atmosphere and nosedive, at about two
kilometres a second, into a warship and detonate conventional
explosives. The new missile could be ready for testing by 2012.
China's missile might be vulnerable, some experts say, to America's
newest Aegis intercept missiles, which are launched from ships. But a
different type of countermeasure could be even more effective. America
and France are among a few countries developing powerful lasers to shoot
down missiles. As a former American battle-group commander notes, a
nuclear-powered aircraft-carrier generates enough electricity to power a
small city, let alone a powerful laser. “Literally, that's ammunition,”
he says: “directed energy” which can be delivered by laser. And no
missile can travel as fast as light.
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