Yet tomorrow is creeping closer, if ever so slowly, toward that vision of laser weapons for land, sea, and air. In this slideshow, we'll take a look at what's been accomplished so far by the U.S. military-industrial complex, what's coming next, and what never really got off the drawing board.
“We are in the process of developing a laser weapon prototype for the naval surface fleet to counter small unmanned aerial vehicles and small-boat threats,” Chief of Naval Research Rear Adm. Matthew Klunder said in a statement in August.
Over three days at sea during that particular demonstration, the laser was operated at high power more than 35 times and "withstood the stresses" of waves in excess of seven feet high, according to Northrop Grumman. The Maritime Laser Demonstrator, installed on a decommissioned Spruance-class destroyer, the USS Paul Foster, also was the first laser system to be integrated with a ship's radar and navigation systems.
"The results show that all critical technologies for an operational laser weapon system are mature enough to begin a formal weapon system development program," Steve Hixson, vice president, space and directed energy systems at Northrop Grumman's Aerospace Systems sector, said in a statement. "Solid-state laser weapons are ready to transition to the fleet."
The 13.3-kilowatt Gamma laser was tested at a beam quality of 1.4, exceeding the design goal of 1.5. (Perfection in laser beams merits a 1.)
The ground-based Skyguard was derived from the Tactical High Energy Laser (THEL) system that Northrop Grumman developed for the U.S. Space and Missile Defense Command and for Israel's defense ministry. The THEL Testbed, developed in the late 1990s, was in residency at the Army's White Sands Missile Range in New Mexico.
In March 2009, under the JHPSSL program, Northrop Grumman said it had coaxed a solid-state laser past the 100KW mark -- a record for an electric laser. It got there by combining seven laser chains, each producing about 15KW of power, to produce a single beam of 105.5KW. Note that the 100KW level is generally considered the threshold for "weapons-grade" lasers.
At that time, the seven-chain JHPSSL laser demonstrator ran for more than five minutes, with beam quality of better than 3.0. As of December 2010, the system had logged more than six hours of operating time at power levels greater than 100KW.
The plan with the Airborne Laser was to catch ballistic missiles in their launch phase, when they're most vulnerable. The ABL, equipped with a "megawatt-class" laser, would fire from that bulbous nose to heat up the side of the missile, weakening it enough to knock it out of commission long before it could reach targets in the U.S. At one point, the Pentagon thought it would build as many as seven ABL aircraft, but in 2009, Defense Secretary Robert Gates put the kibosh on plans to build a second plane and consigned YAL-1A to a humbler fate as nothing more than an R&D effort.
The image sequence here shows the infrared trail of the target missile breaking up in flight as it was zapped.
"With this successful experiment, the Airborne Laser Testbed has blazed a path for a new generation of high-energy, ultra-precision weaponry," Michael Rinn, vice president and ALTB program director at Boeing, said in a statement. "ALTB technology and future directed-energy platforms will transform how the United States defends itself and its friends and allies. Having the capability to precisely project force, in a measured way, at the speed of light, will save lives."
A few weeks earlier, the ATL had made a laser strike on a stationary ground target. As Boeing described the results, "the laser beam's energy defeated the vehicle." By "defeated," Boeing meant that the target was made temporarily or permanently unavailable for its intended use.
In July 2011, Predator drone maker General Atomics won the contract from DARPA to build the Demonstrator Laser Weapon System (DLWS) for HELLADS. General Atomics says it is pursuing a "new approach to electric lasers" that joins "the high storage density of solid-state with the efficient heat removal of flowing liquids."
Following the ground testing of the DLWS in 2013, the laser demonstrator looks likely to be integrated onto a B-1B Lancer aircraft. (See DARPA's illustration of that above.)
In 2007, an earlier version of Laser Avenger showed off its prowess -- in tests -- at neutralizing IEDs and unexploded ordnance on the ground.
"If a laser beam is intense enough, its electro-magnetic field is strong enough to rip electrons off of air molecules, creating plasma," George Fischer, lead scientist for the project, said in a story by Picatinny's public affairs staff. "This plasma is located along the path of the laser beam, so we can direct it wherever we want by moving a mirror."
Where you might want to direct it is at, say, an enemy vehicle or an unexploded artillery shell.
In a FEL system (video), laser light is generated by sending high-energy electrons through a series of magnetic fields, and the resulting beam could be immensely powerful. And an important distinguishing characteristic is the ability to tune the beam to different wavelengths, which could help it better deal with the vagaries of the atmosphere at sea.
But right now, FEL systems are huge and inefficient, and practical systems are a long, long ways off. A report issued last spring by the Center for Strategic and Budgetary Assessments, a Washington, D.C., think tank, said that it might not be until "the late 2020s" that we see ship-based FELs "with power outputs sufficient to interdict more hardened targets, including ballistic-missile reentry vehicles."