Directed Energy Arrives on the High Seas
The guided-missile destroyer USS Preble (DDG-88) has achieved a significant milestone in the development of shipboard directed-energy weapons, successfully engaging and destroying four unmanned aerial vehicles during live-fire testing in the Pacific. The engagements were conducted using the High Energy Laser with Integrated Optical-dazzler and Surveillance (HELIOS) system, a 60-kilowatt-class laser weapon developed by Lockheed Martin and integrated into the ship's Aegis combat system.
The tests, conducted over several days at the Pacific Missile Range Facility off the coast of Hawaii, demonstrated the HELIOS system's ability to detect, track, and engage small drone targets at operationally relevant ranges. All four engagements resulted in the destruction of the target, with the laser burning through the drone airframes in a matter of seconds. The results represent the most successful shipboard laser weapon test to date and mark a critical step toward the operational deployment of directed-energy defenses aboard US Navy warships.
How HELIOS Works
The HELIOS system combines a high-energy fiber laser, a sophisticated beam-control system, and a multi-function optical sensor suite into a single weapon station that can be installed aboard Arleigh Burke-class destroyers. The system is designed to operate as part of the ship's existing Aegis combat system, receiving targeting data from the ship's radar and other sensors and engaging threats under the direction of the combat information center.
At 60 kilowatts, the HELIOS represents a meaningful increase in power over earlier shipboard laser prototypes. The Navy's previous Laser Weapon System (LaWS), deployed aboard the USS Ponce in 2014, operated at approximately 30 kilowatts and was capable of engaging small boats and drones at short range. The HELIOS roughly doubles that power output, extending the effective engagement range and reducing the time required to disable or destroy a target.
The Physics of Laser Defense
Directed-energy weapons destroy targets by concentrating a beam of coherent light on a specific point, heating the material until it fails structurally or its internal components are destroyed. Against small drones, which are typically constructed from lightweight composite materials and carry volatile lithium-polymer batteries, the effect can be dramatic — the laser can burn through the airframe in seconds, causing the drone to break apart or ignite in flight.
The advantage of a laser over a conventional kinetic weapon — a missile or a gun — is primarily economic. A single engagement with the HELIOS costs roughly the equivalent of the electricity needed to power it, estimated at a few dollars per shot. By contrast, a Rolling Airframe Missile (RAM), the Navy's current primary short-range air defense weapon, costs approximately $1 million per round. When defending against swarms of cheap drones, the cost-per-engagement advantage of a laser is transformative.
There are limitations, however. Laser weapons are affected by atmospheric conditions — rain, fog, humidity, and sea spray can all degrade beam quality and reduce effective range. The 60-kilowatt power level, while sufficient for small drones, is not yet adequate for engaging faster, more durable threats like anti-ship cruise missiles. And the system's power demands place additional strain on a warship's electrical generation capacity, which is already under pressure from modern radar and electronic warfare systems.
