Those Far Flung Ships

Well it is the 21st century after all, So it should not come as a shock to read on Wired: “Navy Wants Lasers on Marines’ Trucks to Shoot Down Drones”.

If there was any doubt that the military has new confidence in its forthcoming laser arsenal, the Navy’s top geeks want to outfit Marines with a laser cannon to shoot small drones out of the sky. … So, the specs. The idea is to get a laser cannon weighing less than 2500 pounds mounted onto a Marine Humvee or comparable truck. The cannon needs to provide a “minimum optical output power” of 25 kilowatts, with an eye toward scaling up to 50 kilowatts, for a two-minute full-power blast.

The Marines need a truck to tote the power source for their laser. The Navy has been redesigning its vessels to increase the output of electrical power. The Gerald Ford class of aircraft carriers will produce three times the electricity as their predecessors. They need it, among other things, to operate their electromagnetic catapult.

And there’s an insatiable hunger for the power to run gizmos now on the drawing board. Whether it is catapaults, railguns or lasers, the limiting factor in sea power may be electrical power. A NavSea primer describes the plethora of applications that energy weapons, or energy based weapons have at sea. Stuff to shoot down missiles. Stuff to burn holes in small boats. There are even devices which can stop a vehicle or aircraft by disabling its electrical systems or disperse crowds by bathing them in a kind of microwave heat ray. All require electricity, some in sudden and massive spikes.

To provide large amounts of electrical prime power, new types of rotating machines were studied, including flywheels, conventional alternators, homopolar generators, rotary flux compressors, and compensated pulsed alternators. These machines attempted to produce fast, high-power pulses using special materials to reduce losses, eddy currents, and mechanical stresses.

The magazine of future naval warships will be a battery of some sort. Doubtless the resulting confusion in nomenclature will drive historians crazy.

But one of the retrograde characteristics of directed energy weapons is that the aiming process reverts to the days of Horatio Hornblower. Directed weapons are mostly line of sight. They cannot loop over hills or mountains. At least not yet. Boeing is working on something called the Tactical Mirror Relay system, which reduces the distance beams travel through the atmosphere (losing energy in the process) by bouncing it off UAVs or aerostats. But they need help to do it. And that help comes from stuff that flies around or circles in orbit.

Which brings us to the ultimate matchup, of which the Marine laser and the enemy drone are the simplest case. The ultimate matchup is the Sensor versus the Energy weapon.

The United States’ status of a superpower depends in large part on its control of space. Satellites are used for communication, surveillance, targeting, navigation and electronic warfare. Without space power the United States couldn’t operate drones. GPS would go out. It would be blind. But directed energy weapons would put all those assets at risk. In 2006 the Telegraph reported that China test-blinded US satellites by directing lasers at their sensors.

The relationship between the Sensor and the Energy weapon is an interesting one. Without Sensors directed energy weapons will lack targeting information. The horizon would once again limit what you could aim at. But directed energy weapons have the potential power to blind the satellites or drones. Show an eye and the light will blind it. But without the eye, how to aim the energy weapon? The tactical relationship between the two is interesting.

The mediating factor is electrical power.

China has one big disadvantage in a directed energy contest over space. If it is is restricted to ground based weapons based on their territory then China would be at a major disadvantage to any seapower whose ships, able to lug around huge generating plants in the form of their engines, could roam the world with their energy weapons. A maritime power’s window onto the space would be much bigger than almost any landbased power.

They could attack multiple targets at once. They wouldn’t have to wait for each target to come into view like a duck in a shooting gallery. The ships could simply hit the ducks simultaneously.

When America inherited the role of British empire it did so largely by inheriting the mantle of sea power. Perhaps never has control of the sea been so important as these early years of the 21st century. Whoever controls the sea has direct power over the undersea fiber optic cables that carry information across the planet; who rules the waves controls the vast flows of oil and merchandise which make a global economy possible. Now we find that last but not least, huge power sources at the sea have the power to burn up anything in orbit.

America still rules the waves. That is perhaps its greatest single trump card. Two hundred years ago another maritime power struggled against an invincible conqueror on land. Napoleon Bonaparte’s armies were unbeatable. But powerful as he was on land, his influence ended at the water’s edge. His ports were blockaded. He could not even cross the channel and turn his might on a small island only two dozen miles away from France itself. Mahan described Britain’s advantage memorably: