Making Laser Weapon Systems that the warfighter actually trusts is all about getting the “illities” right.

Colonel Steven D. Gutierrez of U.S. Army RCCTO made an interesting LinkedIn post on November 11^th 2024 covering RCCTO’s efforts to improve and field “tactically relevant” High Energy Lasers

A question in that chat of “what is the working definition of “tactically relevant” High Energy Lasers?”

Was met with a response of: – a HEL capability that is inclusive of and gets after the other “Illities” beyond just lethality – maintainability, affordability, sustainability, reliability, survivability, etc.

This is a great list of capability requirements. Lets try to dive deeper into a more specific understanding of what these “illities” might mean. To do this, It could be useful to investigate the term Design Reference Mission which is an outline of what a weapon system must do to be considered effective for the warfighter(s) supported.

A DRM outlines:

•The objectives of the mission (e.g., destroy, disable, or deter targets)

•The operational environment (e.g., maritime, urban, desert, or space)

•The threats and challenges the system will face (e.g., drones, ballistic missiles, mortar rounds).

•The performance requirements needed to accomplish the mission (e.g., engagement range, power levels, accuracy)

•The constraints like power availability, weather conditions, or other logistical limitations 

The goal is to create a comprehensive context in which the weapon system can be designed, developed, and tested, ensuring that it meets mission-critical capabilities.

Here’s an example of some DRMs that might be made for a HEL system:

1. Drone and UAV Defense
Mission Objective: Protect a forward operating base from swarming UAV attacks.
Operational Environment: Hot desert with high levels of dust and wind.
Threats: Low, slow, and small drones attempting to penetrate the base’s perimeter.
Performance Requirements: Ability to detect, track, and engage multiple small UAVs at varying altitudes and ranges (e.g., up to 5 km).
Constraints: Limited power supply and harsh environmental conditions.

2. Shipborne Defense Against Anti-Ship Missiles
Mission Objective: Protect a naval vessel from incoming anti-ship missiles.
Operational Environment: Open ocean, with sea state 3-4 (moderate waves) and variable weather conditions.
Threats: High-speed, low-altitude missiles using evasive maneuvers to avoid detection.
Performance Requirements: Rapid target acquisition, high-speed tracking, and high-power laser engagement at ranges of up to 10 km.
Constraints: Ship movement, limited deck space, and seawater corrosion.

3. Mobile Army Convoy Protection
Mission Objective: Protect a convoy of vehicles traveling through hostile territory.
Operational Environment: Urban terrain with potential civilian interference and line-of-sight challenges.
Threats: Mortar rounds, IEDs, and armed drones.
Performance Requirements: Quick response time to intercept incoming projectiles (e.g., within 2 seconds). Ability to operate from a moving platform.
Constraints: Power limitations on mobile platforms, vibration, and cluttered environments.

4. Space-Based Asset Protection
Mission Objective: Defend space assets like satellites from anti-satellite (ASAT) weapons.
Operational Environment: Low Earth orbit (LEO) with microgravity, vacuum, and extreme temperature fluctuations.
Threats: Kinetic kill vehicles or high-speed debris targeting satellites.
Performance Requirements: Precise targeting at distances of hundreds of kilometers with minimal power consumption.
Constraints: Limited onboard power and strict weight limitations.

5. Airborne HEL Platform for Counter-Rocket, Artillery, and Mortar (C-RAM)
Mission Objective: Intercept incoming artillery shells or rockets targeting a critical military installation.
Operational Environment: Mountainous terrain with variable atmospheric conditions.
Threats: High-speed, low-trajectory rockets or mortars.
Performance Requirements: Extremely rapid detection and engagement, with the ability to neutralize threats within seconds of detection.
Constraints: Altitude, limited space, and weight restrictions on airborne platforms.

(Credit to ChatGPT for the DRM definition and DRM examples)

Now these five DRMs have a lot of information so lets consider getting a bit more specific. The drone and UAV defense DRM is popular in the news based on vehicle mounted lasers for drone defense such as the Locust, Dragon Fire, and more with different articles covering them so we will focus on that.  

Drone and UAV Defense
Mission Objective: Protect a forward operating base from swarming UAV attacks.

For Mission Objective, much of the systems gaining prominence suggests that HEL integration to mechanized platforms or in a palletized configuration is an essential part.  

Swarms of UAVs are also considered, but what number of UAVs constitutes a “swarm”? To learn this, we can look to the Defense Systems Information Analysis Center (DSIAC) which defined swarms in 2020 using the following definitions in its sources:

The FAA defines a swarm as “an operation of more than one UA in which all UAs operate in unison to commands from one PIC, who commands them all through a common link” in the Order JO 7200.23A policy [5].

The Counter-Unmanned Aircraft System (CUAS) Capability for Battalion-and-Below Operations [6] defines a swarm as a group of 40 or more small UAS (sUAS) where the following criteria are met:

•The group seems to act as a unit, but each individual executes local behaviors.

•Not all members know the mission.

•Swarming members communicate with one another.

•Each sUAS will not focus on a designated position, but rather will position itself relative to other sUAS.

So, the DSIAC article concludes with “Although there does not seem to be a consensus on the definition of UAS swarms, all preliminary definitions mention multiple UAS (anywhere from 2 to 40+)”

Operational Environment: Hot desert with high levels of dust and wind.

Considering that a key vulnerability to laser lethality and effectiveness is dust, smoke, or other particulates that might block some (or all) of a HEL’s beam path this will mean that system performance is degraded when inclement atmospherics are present around the area of operations.
Threats: Low, slow, and small drones attempting to penetrate the base’s perimeter.

So for the purpose of defining what this looks like we can consider the U.S. Army’s ATP 3-01.81 Counter-Unmanned Aircraft System Techniques. Below is a picture of ATP 3-01.81’s Figure 1-1 providing greater context on the low, slow, small (LSS) terms.

How the Iranian Shahed 136 Works

Demonstration of a Chinese Drone Swarm Launcher

Performance Requirements: Ability to detect, track, and engage multiple small UAVs at varying altitudes and ranges (e.g., up to 5 km).

This topic is covered in another SemQuest blog entry. Just so you don’t need to jump around we’ll consider the U.S. Army’s stated requirements  for Group 3 UAS for nominal engagements:

•Nominal radar handoff (State vector, Covariance, Latency)

•Track Target – 8 km (Above and Below the Horizon (ATH and BTH))

•Identify Target – 6.5 km (Operator in the loop, 60-second ID time)

•Defeat Target – 4-5 km

Based on the fact that the Shahed video states that these low budget cruise missile configured drones have been observed swarming in groups of 5-10, perhaps this should be considered the baseline for “multiple small UAVs”.

Constraints: Limited power supply and harsh environmental conditions.

Power supply is where systems employed by the Army and Air Force could run into difficulties. Providing power to the laser could be a large technical challenge considering many mechanized vehicles were designed prior to taking a laser into account. The Navy might have an easier problem to solve here since on board ship systems can likely offer more energy margin.

Weather considerations can be difficult to plan around for any weapons systems. Arguably, even with potential challenges in effectively wielding lasers in foul weather conditions. The stronger defense posture offered in fair laser weather conditions would help bracket would be attackers into operating in only the worst of weather conditions when they know lasers cannot be used as effectively. 

Now that we have some extra context added to the cUAS DRM, lets consider how it fits into the “illities” mentioned by Colonel Gutierrez. For comparisons, we’ll consider the fact that Laser Weapon Systems will be compared to other systems that offer that same sort of general capability. For the purpose of some of these comparison the USMC’s Marine Air Defense Integrated System (MADIS) will be used.

Lethality – For lethality, a range of different system power levels could be used. To narrow things down, we’ll consider the U.S Army “Sweet Spot(s)” power ranges from 20 to 50 kW:

•20 kW with a 4 cm beam size = an Average Power Density of 3.1 kW/cm²

•30 kW with a 5 cm beam size = an Average Power Density of 3.0 kW/cm²

•40 kW with a 5.5 cm beam size = an Average Power Density of 3.3 kW/cm²

•50 kW with a 6.5 cm beam size = an Average Power Density of 3.0 kW/cm²

Each of these power density values are high enough to yield the 2.8 kJ/cm² if held for 1 second on target.

Maintainability – For maintainability, we can relate the maintenance needs of a Mk44 Bushmaster which can take between 10-20 hours of maintenance to keep operational.

Laser systems can have a disadvantage here as developmental systems in need of a lot of maintenance handling to keep up performance. Maintenance checks can also require advanced laser power detection equipment to be truly effective.

Affordability – For affordability, the MADIS system’s  FY20 budget for (26) systems purchased at $150 million (just over $5.8 million each). The Stryker systems are also worth comparing at $130 million for 91 vehicles (just over $1.4 million each).

Press releases are slim for laser weapon system cost information, but smaller systems such as AIM’s Fractl can cost less at $4.9 million each or as much as $83 million for larger 300 kW systems.

Sustainability – In this category, lasers might have a definite edge from a munitions standpoint since the “bullet” of a laser weapon system is simply highly focused light. Guns and missile systems will have to restock their magazines periodically whenever they’re in need of more ammunition.

However, from a system components standpoint, laser weapon systems might be at a disadvantage with the long lead times often tied to the technically advanced optics needed in any laser weapon system. Ensuring that these components can stand the test of time during deployment, and be manufactured more quickly is key for these systems to be truly sustainable.

Reliability –  Information on malfunction rates for weapons is not easy to find. But we can consider the efforts to keep the Mk44 and the M242 systems commonality with logistics parts at a rate of 60% and at a rate of 90% for operator maintenance training an impressive achievement.

Commonality amongst laser weapon systems parts is also desired.

Survivability – Survivability of laser weapon systems could be difficult to achieve thanks to fragile optical components that might break in transit, in bad weather, or when in close proximity to hostile fires. Yet, there might be a clear way forward by stowing HEL systems to make them more survivable when in transit or in severe weather.

So, if you’re making Laser Weapon Systems you need to be asking all the right questions. We think one of those right questions is:

Can you out “illity” a gun truck?