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Laser Weapon System (LaWs)

December 11, 2017

By: Robin Staton
Special Guest Writer

My dual objectives with this blog entry are first, to provide a short historical perspective on what it has really taken to get a true laser weapon on a ship with the necessary protocols and procedures in place that are required to actually use the weapon; and second, to briefly review the role Dahlgren has played in achieving that milestone.

 
 Credit: Alvim Corréa from the 1906 French edition of H.G. Wells’ War of the Worlds. Courtesy Wikipedia Commons
Energy beam weapons have been a staple of science fiction for more than 100 years. Figure 1, illustrating War of the Worlds  published in 1898, depicts a “Heat Ray” weapon used by the invading Martians. Star Trek fans from the early 1960s to today will undoubtedly recognize the Phaser. Like many of today’s technologies, including cell phones, medical monitors, television, robots, satellites, and countless others, the advantages of such devices are often seen (and explored through science fiction) long before anyone has any idea how to go about actually building the device.

Thus, the potential advantages of laser weapons were understood well before the construction of the first operating laser in 1960 by Theodore H. Maiman at Hughes Research Laboratories. Those advantages include speed-of-light energy transmission over an essentially straight path to the target (including highly maneuvering targets) and a reduced logistics burden compared to gun projectiles and missiles with explosive warheads and very energetic propellants. All the expensive components of the laser weapon remain on the ship and can be used again and again. The target receives only the destructive benefits of the energy delivered.

From a historical perspective, it is interesting to observe that the development of the first deployed Navy laser weapon covers virtually the same time period as the Navy’s use of Dahlgren for weapon testing, development, and evaluation. The quantum mechanical theory of stimulated light emission, fundamental to understanding how a laser works, was proposed by Albert Einstein in 1917. The Navy ballistics testing facility (then the “Lower Station” of the Naval Proving Ground, Indian Head, Maryland) was established at Dahlgren in 1918. Laser weapon development from sound scientific theory to operating, useful weapon on a Navy ship therefore covers roughly the same 100 years as the history of the Navy base at Dahlgren.

As a point of reference, and to put current laser weapons in a historical framework, gun technology development goes back at least 775 years (circa 1241) and significant advances in gun technology still occur on a fairly regular basis. Explosive technology development (think gunpowder) traces its roots to 9th century China—more than 1100 years ago. Thermal weapons (think fire, molten tar) are much older still. Lasers are very new on the weapon technology scene.

At the current pace of technology development, you have to wonder where lasers weapons might be in 25 to 50 years, much less another 100 years. What can be said with fair certainty is that Dahlgren-led efforts in the LaWS program have resulted in the Navy now having one deployed, operational laser weapon in 2017.The numbers of systems, the power levels, and the operational utility will only increase from here. In fact, recent news reports suggest the next-generation Navy laser weapon may arrive in only two years and will have a power level over four times greater than the current LaWS.

 
 Mid-Infrared Advanced Chemical Laser (MIRACL)
 
 Sea Lite Beam Director
The Navy has had an interest in laser weapons since the 1970s, in part because ships could carry the very large lasers of the time that could generate the megawatts of continuous laser power needed to quickly destroy hard targets like missiles and aircraft.  First efforts focused on chemical lasers that could generate very high powers—and actually shoot down large missiles in flight. These systems ultimately proved to be unsuitable for a number of reasons, including operating frequency and logistics and safety burdens.

Early work at Dahlgren related to laser weapon technology in the 1970s was focused more on semi-active laser (SAL) illumination of targets for guiding 8- and 5-inch SAL-guided projectiles. There was also work on the SAL seekers themselves, and on the target acquisition, target tracking, laser beam pointing, and target aimpoint selection needed to keep the laser pointed at the spot on the target you wanted to hit with the guided projectile. All these, and other, technical efforts at Dahlgren in the late 1960s and 1970s would support creating the expertise needed for the Navy’s future laser weapon research.

One Dahlgren technical discipline that traces its roots back to the very birth of Dahlgren and before, and that helped tremendously in preparing Dahlgren scientists and engineers for laser weapon development, is the discipline of target interaction, lethality, and vulnerability. Originally a ballistics problem of projectile versus armor plate, the ensuing 100 years saw the concepts expanded to include aircraft, warheads, bombs, missiles, hazards of electromagnetic radiation to ordnance, EW, high-power microwaves, cyber warfare, and lasers. Dahlgren was working both theoretical and experimental issues associated with laser/ target interactions and lethality long before there was a LaWS Program. In fact, the first IPG Phototonics Corporation’s solid-state lasers purchased at Dahlgren were used for laser lethality studies, not the LaWS. Figures 4 and 5 illustrate a steel plate with laser damage and some of the first IPG laser cabinets at Dahlgren.
 
 Half inch steel plate penetrated by a 39 kw Laser Strike
 
 IPG Laser Cabinets

Included in the early Dahlgren weapon research category was the development of the target signature forward-looking infrared (TSF) sensor to collect highly accurate radiometric infrared target signature data on as many targets as possible for weapon system acquisition, track, and beam pointing. The TSF was used during two instances of note.

In the first instance, Hughes Aircraft/TRW was attempting to demonstrate the first successful shoot-down of a missile by TRW’s 2-megawatt high-energy laser at San Juan Capistrano, California. The companies were unable to point and track a target with their system, and were under pressure from President Carter, who threatened to kill the program if they weren’t successful. John Albertine, PMS-405, solicited Dahlgren’s help, so a team took the TSF on a tracking mount to observe the tests.

During testing, Dave Troyer, the lead on-site Dahlgren engineer, called Roger Horman, a supporting scientist at Dahlgren, each night to discuss the issues and failures of the day’s testing and get advice on what to do next. After the testing started to be successful, Albertine became convinced the on-site Dahlgren engineer was a genius when, in fact, he just knew where to get good, competent technical advice. (Albertine, however, was never convinced otherwise.) In the end, Dahlgren helped Hughes Aircraft make the necessary adjustments to successfully shoot down a missile with an HEL. Dahlgren’s imagery was presented to the President, and the program was continued. As expected, Dahlgren received no credit nor was anyone from Dahlgren invited to the resulting celebration. It’s rumored, however, Troyer did receive a coffee mug in recognition of Dahlgren’s contributions.

In the second instance, the Johns Hopkins University Applied Physics Laboratory (JHU APL) requested Dahlgren engineers’ participation during a laser test at a Pratt and Whitney facility in West Palm Beach, Florida, where there was a several-hundred kilowatt high-energy laser (HEL) and where dynamic phenomenology and lethality tests were conducted. With JHU APL’s help, Dahlgren was able to install its 8–12 µm imager co-linear with the 3.3 µm HEL. This was the first test ever to determine atmospheric effects of an HEL on the main spectral band of the proposed imaging system for the Navy’s HEL system, and some of the premier theoretical experts in the country were in attendance. As the laser was irradiating, the 8–12 µm imagery showed what appeared to be the equivalent of many bubbles rapidly being formed, growing, and disappearing. The experts went about trying to explain the complex physics associated with an HEL propagating over this path. The engineers asked if they could walk along the path between the HEL system and the target. What they found were thousands of dead bugs! The HEL system was the biggest and most expensive bug zapper ever built.

Since the 1970s, other Dahlgren technical efforts in lasers included developing, testing, and at-sea evaluation of laser “dazzlers” intended to temporarily blind approaching threats and turn them away. Equally significant over the past 30 years have been projects at Dahlgren in electro-optical (EO) sensor development; target acquisition and tracking research, development, test, and evaluation; several projects in laser radars; multi-sensor integration efforts that include radar, EO, and electronic warfare (EW) sensors; and fire control and combat system software development and test. These systems provided crucial experience in the real-world problems involved in ship modifications, installation, and maintenance of EO systems that would prove capable of operating for well over a year in a difficult at-sea environment.

It is very fair to say that by the time Dahlgren was designated lead systems engineer for the laser weapon system in March 2007, NSWCDD scientists and engineers had accumulated decades and decades of highly relevant weapon system experience over scores of technical disciplines. They knew very well, for example, that if target acquisition doesn’t work, the system doesn’t work. If target tracking doesn’t work, the system doesn’t work. If you cannot select an appropriate aimpoint and maintain the laser on it, the system doesn’t work. If the laser is not lethal for the target at the target’s range, the system doesn’t work. If the software doesn’t work, the system doesn’t work. If the system cannot be maintained in the field, the system doesn’t work. If you cannot address safety and operation issues, then it doesn’t matter if the system works or not—you will never be allowed to use it.

Everything has to work—all the components, in all the relevant environments, and under the control of the operators. And not only that, everything has to simultaneously work together. How inconvenient! From guns to rockets to missiles to entire multi-weapon systems, these lessons had been learned and constantly reinforced over and over at Dahlgren during the past 100 years. Figure 6, from a 2009 LaWS test, illustrates what happens when everything works.
 
 BQM-147A during LaWS engagement

It is easy to forget just how many man hours and years it really takes to achieve the desired success.  Building a laser weapon requires a diverse team with a wide range of skills, and sometimes teams competed for troubleshooting time. The laser team had to spend a great deal of its time on alignments, and these usually took top priority. So some of the other teams decided they too needed to “align” their systems, even though it isn’t really relevant, just to get the time needed to work on the system.

Because of the long hours one needs to work when testing the system, often there isn’t time to make it to the mess when meals are being served. This is especially problematic when doing shipboard testing and integration. So when embarking on testing, one needs to make sure the team has enough “mission food” to sustain it through the long hours of testing. The official LaWS mission food always included Oreos.

 
 LaWS Beam Director during testing at Naval Weapons Center, China Lake
The Afloat Forward Staging Base (Interim) USS Ponce (AB(I) 15) conducts an operational demonstration of the Office of Naval Research (ONR)- sponsored Laser Weapon System (LaWS) while deployed to the Arabian Gulf. (U.S. Navy photo by John F. Williams/Released)
LaWS has now been deployed on a U.S. Navy ship operating in the Persian Gulf since 2014. To quote Wikipedia and CNN:

“The AN/SEQ-3 (XN-1) Laser Weapon System or LaWS is a directed energy weapon developed by the United States Navy. The weapon was installed on USS Ponce for field testing in 2014. In December 2014, the United States Navy reported that the LaWS system worked perfectly, and that the commander of the Ponce is authorized to use the system as a defensive weapon.”

While there are some inaccuracies in the subsequent article, including attributing the system development and construction to Kratos Defense and Security Solutions, Inc., this part appears to be accurate and is supported by numerous additional sources.

The official program start in March 2007 kicked off greatly expanded efforts in system design, component procurement, utility studies, lethality studies, and many other investigations needed to develop the planned system. Dahlgren scientists and engineers drew on a very wide community of Navy and DoD research and development establishments, as well as a wide array of university and industrial firms. Parts were bought from many places, and talents were used from many places. However, the core of the development, fabrication and assembly, testing, modification, and improvement remained at Dahlgren. The system development was funded by the Navy’s Directed Energy and Electric Weapons Program Office. Articles available on the Internet, as well as Dahlgren’s Leading Edge publication already referenced provide much more system and weapon development detail.

One question which might be asked is: “is LaWS truly a weapon?” One definition of “weapon” (again from Wikipedia) is “...any device used with the intent to inflict damage or harm to living beings, structures, or systems.” Clearly, LaWS is a weapon by this definition. A very legitimate question is then: “just how good a weapon is it?” Is it a really useful weapon? After all, in some situations, a coffee mug or beer bottle are truly useful and effective weapons, but they do not have wide utility in that function across multiple situations.

The LaWS laser is currently a multi-kilowatt laser, not a multi-megawatt laser. A single stick of dynamite delivers about 1 megajoule of energy. A 1-megawatt laser delivers 1 megajoule in 1 second. LaWS is not yet throwing sticks of dynamite toward its target, at least not very quickly.

That said, few people would dispute that a .50 caliber sniper rifle with a good telescopic sight is a deadly weapon in skilled hands. It is not nearly as powerful as the 76 mm and 5-inch guns found on many current Navy ships, but in many situations it has very high utility. The .50 Browning machine gun round was introduced in 1921 and was based on the 30-06 Springfield cartridge developed around 1900 (again, more than 100 years of development history.)

I view today’s LaWS as a weapon that is very analogous to an accurate .50 caliber Browning sniper rifle with a really good telescopic sight. LaWS delivers roughly twice the muzzle energy of a .50 caliber machine gun round every second. In addition, the LaWS “telescopic sight” is inertially stabilized and has a video tracking capability that, combined with zero time-of-flight, makes it accurate for shooting a moving target. Like the sniper rifle, there are a number of targets LaWS can kill at useful ranges. A partial list of suitable targets for LaWS includes many UAVs/drones; some missile, rocket, and mortar rounds; minimally protected fuel tanks; exposed boat motors; and a wide array of optical sensors. For both weapons, the reasonable target list is quite large.

There are also a good number of targets that LaWS cannot (currently) kill such as army tanks, armored personnel carriers, or large steel boats. The .50 caliber round will not stop those either, but LaWS at least has a really good chance of destroying sensors on those (moving) vehicles and possibly even detonating exposed ordnance on the vehicles. (Because of time-of-flight and other issues, unguided ballistic bullets do not perform nearly as well.) The LaWS sensor system, like the telescopic sight, is also useful without even firing the weapon for target identification, target monitoring, and developing clues on target intentions.

Past weapon technology development in particular disciplines have continued for centuries. Examples include the blade, bow and arrow, guns, explosives, poisonous chemicals, rockets, thermal weapons, bombs, and mines. Even the current Predator-launched Hellfire attacks have a history that includes rockets, glide bombs, and Maverick missiles launched from the Ryan Aeronautical Company’s Firebee drones during the Vietnam War period, torpedoes dropped from remotely controlled DASH [drone antisubmarine helicopter] in the late 1950s/early 1960s, and even the research on remotely controlled aircraft intended to be the Navy’s flying torpedoes or flying bombs in the 1920s (subject of another blog). Although the theoretical scientific knowledge and the practical optical technology and techniques needed to build a laser existed in the 1930s, the laser was not successfully constructed until 1960. In spite of considerable work on laser weapons since the 1970s, it is still fair to say that laser weapons are in their very early infancy. It is also fair to say that the operational deployment of a true laser weapon on a Navy ship operating in a high-threat environment represents a significant historical milestone. That milestone was accomplished in no small part because of Dahlgren’s engineers, scientists, and technicians.