By Troy Turner
The U.S. Navy, actively engaged in defending Red Sea shipping against missile and drone attacks and with an eye toward China’s rapid military growth, is expediting research on the merits of arming its ships with lasers amid concerns about the limitations of conventional weaponry.
Those concerns include limited munition supplies in ship magazines and unfavorable cost-exchange ratios.
Adding shipboard lasers on a widespread basis, however, requires more development and successful testing be completed, funding approved, and production ramped up, according to the Congressional Research Service in a special report to Congress released July 1.
Military and defense industry leaders working in Huntsville, such as the Army’s Space and Missile Defense Command and Redstone Arsenal, also are among those answering the call for rapid advance in the development of weapons using directed energy such as lasers and microwave technology.
Such weapons are being developed by multiple parts of the Department of Defense, not just the Navy, and have potential application to military aircraft and ground forces equipment, not just surface ships, the research service reported.
Rearming the surface fleet
“Although Navy surface ships have a number of means for defending themselves against surface craft, unmanned aerial vehicles (UAVs) and anti-ship missiles, some observers are concerned about the survivability of Navy surface ships in potential combat situations against adversaries, such as China, that are armed with large numbers of UAVs and anti-ship missiles, including advanced models,” the report stated. “Concern about this issue has led some observers to conclude that the Navy’s surface fleet in coming years might need to avoid operating in waters that are within range of these weapons.
“Views on whether Navy surface ships can adequately defend themselves against UAVs and anti-ship missiles might influence perspectives on whether it would be cost effective to spend money on the procurement and operation of such ships.”
The report, titled “Navy Shipboard Lasers: Background and Issues for Congress,” dives into the development and needs for the Navy’s solid state lasers (SSL) program.
Interest quickly became heightened after witnessing the dramatic increase of unmanned aviation, ground and naval assets in Ukraine’s war with Russia, and now the active use of such weapons by Iranian-backed militia attacking vessels in the Red Sea.
“The Navy’s proposed FY2025 budget requests continued research and development funding for some of these efforts,” the report says of laser development. “The issue for Congress is whether to modify, reject, or approve the Navy’s acquisition strategies and funding requests for shipboard laser development programs.
“Decisions that Congress makes on this issue could affect Navy capabilities and funding requirements, and the defense technology and industrial base.”
Staying in the battle
The research report spells out the Navy’s concerns:
“Two key limitations that Navy surface ships currently have in defending themselves against UAVs and anti-ship missiles are limited depth of magazine and unfavorable cost exchange ratios. Limited depth of magazine refers to the fact that Navy surface ships can use surface-to-air missiles (SAMs) and their Close-in Weapon System (CIWS) Gatling guns to shoot down only a certain number of enemy UAVs and anti-ship missiles before running out of SAMs and CIWS ammunition, a situation that can require a ship to withdraw from battle, spend time travelling to a safe reloading location (which can be hundreds of miles away), and then spend more time traveling back to the battle area.
“Unfavorable cost exchange ratios refer to the fact that a SAM used to shoot down a UAV or antiship missile can cost the Navy more to procure than it cost the adversary to build or acquire the UAV or anti-ship missile.”
Procurement costs for Navy air-defense missiles range from several hundred thousand dollars to a few million dollars per missile, depending on the type.
By comparison, SSLs are electrically powered, drawing their power from the ship’s overall electrical supply, and can be fired over and over, indefinitely, as long as the laser continues to work and the ship has fuel to generate electricity.
“Depending on its beam power, an SSL can be fired for an estimated marginal cost of $1 to less than $10 per shot (much of which simply is the cost of the fuel needed to generate the electricity used in the shot).”
The pros of using lasers
Among the potential advantages of developing SSLs, according to the report:
• Fast engagement times. Light from a laser beam can reach a target almost instantly (eliminating the need to calculate an intercept course, as there is with interceptor missiles) and, by remaining focused on a particular spot on the target, cause disabling damage to the target within seconds. After disabling one target, a laser can be redirected in several seconds to another target.
• Ability to counter radically maneuvering missiles. Lasers can follow and maintain their beam on radically maneuvering missiles that might stress the maneuvering capabilities of Navy SAMs.
• Precision engagements. Lasers are precision-engagement weapons; the light spot from a laser, which might be several inches in diameter, affects what it hits, while generally not affecting (at least not directly) separate nearby objects.
• Graduated responses. Lasers can perform functions other than destroying targets, including detecting and monitoring targets and producing nonlethal effects, including reversible jamming of electro-optic sensors. Lasers offer the potential for graduated responses that range from warning targets to reversibly jamming their systems, to causing limited but not disabling damage (as a further warning), and then finally causing disabling damage.
The limitations of using lasers
Among limitations cited for shipboard lasers:
• Line of sight. Since laser light tends to fly through the atmosphere on an essentially straight path, shipboard lasers would be limited to line-of-sight engagements, and consequently could not counter over-the-horizon targets or targets that are obscured by intervening objects. This limits in particular potential engagement ranges against small boats, which can be obscured by higher waves, or low-flying targets. Even so, lasers can rapidly reacquire boats obscured by periodic swells.
• Atmospheric absorption, scattering, and turbulence. Substances in the atmosphere—particularly water vapor, but also things such as sand, dust, salt particles, smoke and other air pollution—absorb and scatter light from a shipboard laser, and atmospheric turbulence can defocus a laser beam. These effects can reduce the effective range of a laser… Lasers might not work well, or at all, in rain or fog, preventing lasers from being an all-weather solution.
• Thermal blooming. A laser that continues firing in the same exact direction for a certain amount of time can heat up the air it is passing through, which in turn can defocus the laser beam, reducing its ability to disable the intended target. This effect, called thermal blooming, can make lasers less effective for countering targets that are coming straight at the ship, on a constant bearing. Other surface ship self-defense systems, such as interceptor missiles or a CIWS, might be more suitable for countering such targets. Most tests of laser systems have been against crossing targets… In general, thermal blooming becomes more of a concern as the power of the laser beam increases.
• Saturation attacks. Since a laser can attack only one target at a time, requires several seconds to disable it, and several more seconds to be redirected to the next target, a laser can disable only so many targets within a given period of time. This places an upper limit on the ability of an individual laser to deal with saturation attacks—attacks by multiple weapons that approach the ship simultaneously or within a few seconds of one another. This limitation can be mitigated by installing more than one laser on the ship, similar to how the Navy installs multiple CIWS systems on certain ships.
• Hardened targets and countermeasures. Less-powerful lasers—that is, lasers with beam powers measured in kilowatts rather than megawatts — can have less effectiveness against targets that incorporate shielding, ablative material, or highly reflective surfaces, or that rotate rapidly (so that the laser spot does not remain continuously on a single location on the target’s surface) or tumble. Small boats (or other units) could employ smoke or other obscurants to reduce their susceptibility to laser attack. Measures such as these, however, can increase the cost and/or weight of a weapon, and obscurants could make it more difficult for small boat operators to see what is around them, reducing their ability to use their boats effectively.
• Risk of collateral damage to aircraft, satellites and human eyesight. Since light from an upward-pointing laser that does not hit the target would continue flying upward in a straight line, it could pose a risk of causing unwanted collateral damage to aircraft and satellites. The light emitted by SSLs being developed by the Navy is of a frequency that can cause permanent damage to human eyesight, including blinding. Blinding can occur at ranges much greater than ranges for damaging targeted objects. Scattering of laser light off the target or off fog or particulates in the air can pose a risk to exposed eyes.
The Huntsville connection
Redstone Arsenal in Huntsville is the home to several U.S. Army space and missile commands; and to NASA development work, including Marshall Space Flight Center.
They along with dozens of defense industry contractors large and small are working on or have interests in the development of directed energy assets such as laser technology.
For example, in March a Virginia-based company earned a nearly $63 million contract for work to be performed in Huntsville on the production, integration and sustainment of laser systems and vehicles.
“The systems will provide the warfighter with the ability to effectively identify, disarm and clear unexploded ordnance from an airfield,” according to the Department of Defense.
Another example of Huntsville’s role came in August 2022 with the ribbon-cutting of the Army Space and Missile Defense Command’s new Directed Energy Systems Integration Lab, or DESIL.
DESIL is a 5,400-square-foot facility designed to provide the Army with a consolidated capability to support a full end-to-end directed energy system, meaning an all-in-one site that allows researchers to generate and test their systems without having to assemble it in one location and move to another for live-fire tests.
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Troy Turner is the editor and senior consultant for AlaDefense.com. He can be contacted at [email protected].
The Congressional Research Service report cited in this article was authored by Ronald O’Rourke.
To view the complete report, go to: https://crsreports.congress.gov/product/pdf/R/R44175
Photos: The U.S. Navy has conducted laser tests at sea for more than a decade, including multiple tests on the USS Ponce. (Photos via U.S. Navy/Department of Defense.)
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