POWER July 2013 - 51

ASSET MANAGEMENT
and the country either encouraged or looked
the other way when one of its scientists-now
a revered national hero, A.Q. Kahn-diverted
European centrifuge uranium enrichment
technology to Iran and North Korea.
But the EMP threat extends further down
the threat chain than bad state actors in nasty
neighborhoods. While a nuclear weapon detonated
above a modern country could spread
broad havoc, much smaller devices can use
pulses of radio frequencies to take out specific
targets such as power plants, refineries,
electric substations, and the like, arming terrorist
groups, disgruntled employees, or addled
individuals with asymmetrical weapons
that profoundly challenge conventional arms
control and police capabilities.
In his book, Maloof describes a hypothetical
attack on Washington, D.C., that
completely disrupts the nation's capital
and surrounding areas, including commuElectromagnetic
Rail Guns
Electromagnetic forces are not only a threat
to U.S. infrastructure but also can be the
motive force for advanced weapons. The
U.S. military has been working for many
years on an electrical " rail gun " that would
use magnetic forces to suspend a projectile
in a field and propel it forward at enormous
nications at the Pentagon. The attackers,
he writes, use " small, rifle-sized arms that
shoot not bullets but radio frequencies,
weapons that can be built for about $400
with easy-to-obtain parts. Think of one of
those Super Soaker water guns. " (The U.S.
military is, not surprisingly, also looking at
the use of electromagnetic forces for weaponry-see
the sidebar.)
Maloof also describes how a terrorist cell
with a primitive EMP weapon in the back of a
panel truck could easily bring down a passenger
airplane landing at Washington's Reagan
National Airport. " At the cost of a few thousand
dollars in material and know-how, this
homegrown terror cell kills more than a thousand
people-several hundred passengers on
the planes, the rest in the buildings that take
the full impact of the crashing planes. "
The visions of Franks, Maloof, Pry, and
others about the possibility of an EMP threat
have critics, although their critique is directed
not directly at the physics of an EMP assault
but at the doomsday nature of an attack.
Physicist Yousaf Butt, a Federation of American
Scientists consultant, wrote last year in
The Space Review, " If terrorists want to do
something serious, they'll use a weapon of
mass destruction-not a weapon of mass disruption. "
He said an EMP attack depends " on
complicated secondary effects, " rendering it
less fearsome and less likely.
Starfish and Other Denizens of
the Deep
U.S. scientists learned of the perverse
effects of an EMP in an Atomic Energy
Commission 1962 test explosion of a 1.4
megaton warhead over the South Pacific.
It was called " Starfish Prime, " one of several
tests in the " Operation Fishbowl " series.
The blast caused an electrical pulse
speeds, freed from the friction that limits
conventional guns. Although the Air Force
initially supported rail gun research, the
program has shifted to the Navy, which sees
the weapon as a way to increase its reach
for ships firing at targets beyond what conventional
armaments now allow (Figure 2).
2. Fast and furious. The electromagnetic railgun launcher is a long-range weapon that
fires projectiles using electricity instead of chemical propellants. Magnetic fields created
by high electrical currents accelerate a sliding metal conductor, or armature, between two
rails to launch projectiles at 4,500 mph to 5,600 mph. Electricity generated by the ship is
stored over several seconds in the pulsed power system. Next, an electric pulse is sent
to the railgun, creating an electromagnetic force accelerating the projectile to Mach 7.5.
Using its extreme speed on impact, the kinetic energy warhead eliminates the hazards of
high explosives in the ship and unexploded ordnance on the battlefield. Source: Office of
Naval Research, U.S. Navy
Above sensible atmosphere
Simplifies deconfliction
According to the Navy's research program,
the rail gun would be a " longrange
weapon that fires projectiles using
electricity instead of chemical propellants.
Magnetic fields created by high
electrical currents accelerate a sliding
metal conductor, or armature, between
two rails to launch projectiles at 4,500
mph to 5,600 mph. "
The key to the rail gun, according to
the Navy, is a pulsed electric power system
located on the ship. The electrical
system would produce an instantaneous
burst of electrical energy that would push
a projectile down a rail path and toward
a target. The rail gun would be able to
reach enemy targets some 70 miles in the
distance, far beyond conventional chemical
ballistic, ship-fired missiles.
But development of the weapon hasn't
Missile defense
Surface
warfare
Hypervelocity launch/impact
(MACH 5-7)
Indirect fire
Long range fires
Direct fire
(horizon in 6 seconds)
Enhanced company operations
been easy. Popular Science reports, " Rail
guns require a massive amount of electricity
that current naval ships cannot
spare if they can generate it at all. The
Navy hopes its rail gun will debut on the
next-generation of high-powered ships,
like the Zumwalt class destroyer (currently
slated to enter service in 2015)
by early in the next decade. " The magazine
notes that the Navy has spent some
$240 million over seven years and " the
technology is still very much restricted
to the lab. " Live demonstrations could
come in 2017.
July 2013 | POWER
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