Directed-Energy Weapons

A high-energy laser weapon disables a target by concentrating an intense beam of light on it. It is a type of directed-energy weapon that transfers electromagnetic energy, rather than a projectile's kinetic energy, to damage a target or prevent it from functioning.

How laser energy damages a drone

The principal destructive mechanism is thermal damage. When the target absorbs laser light, that energy becomes heat; damage occurs if energy accumulates faster than it can be dissipated.

• Focusing the beam onto a small area produces a high power density, allowing the illuminated material to heat rapidly.
• Sufficient heating can weaken, melt or burn through material, damaging a drone's structure or essential components and potentially causing loss of flight.
• Disabling a critical component can stop the mission without destroying the entire aircraft; this is a mission kill.
• Lasers can also interfere with optical sensors. Temporary dazzling is distinct from permanent sensor damage and does not necessarily require the destructive heating associated with burning through a structure.

Why tracking and dwell time matter

The beam reaches the target at the speed of light, but destructive effects are not necessarily instantaneous. The weapon must usually keep sufficient energy concentrated on the target for a period called dwell time.

• Sensors and fire-control systems detect and track the drone, while beam-control equipment points and stabilises the laser.
• Target movement, vibration and pointing errors can spread energy over a larger area, reducing heating at any one point.
• The required exposure depends on beam power, spot size, atmospheric transmission and the target material's absorption and resistance to heat.

Operational strengths and limitations

Laser weapons offer precise engagement and a potentially low marginal cost per shot, but they are not an all-weather replacement for other air-defence weapons.

• They require line of sight; terrain, structures or other obstructions can block the beam.
• Fog, clouds, rain, dust and smoke can absorb or scatter laser energy, while atmospheric turbulence can make tight focusing harder.
• Electrical power and cooling capacity constrain sustained operation; a laser does not have unlimited endurance merely because it uses no conventional ammunition.
• A system generally engages targets sequentially, so dwell time and retargeting can limit its effectiveness against numerous simultaneous threats.