CL-20, chemically known as
hexanitrohexaazaisowurtzitane (HNIW), is a
polycyclic nitroamine explosive and the
most powerful non-nuclear single explosive currently in use. It was developed by the
China Lake Naval Weapons Center in the
1980s and features a cage structure with a density exceeding
2 g/cm³.
CL-20 outperforms conventional explosives like
HMX and
RDX by
14–20% in detonation velocity and pressure, while offering a better oxidizer-to-fuel ratio for propellants. The
ε-polymorph is the most stable and dense form, though large-scale production remains costly and complex.
Recent applications include the
AeroVironment Switchblade 300 drone, testing in
Lockheed Martin LRASM and
JASSM-ER missiles, and integration into
Taiwan’s Hsiung Feng missile systems. It was also notably used in the
2024 Lebanon electronic device attacks.
Identified CL-20 manufacturers
CL-20 production is concentrated in a handful of countries, with
China being the only one with true industrial-scale mass production (achieved in 2011). Here's a breakdown:
China
- Sichuan Military and Civilian Co-Innovation Center for New Energetic Materials — led by Guo Changping, developed a nanotech method making CL-20 ~5× more shock-resistant, enabling mass production.
- Beijing Institute of Technology — won China's highest military science award in 2016 for its contribution to CL-20 mass production.
United States
- Northrop Grumman — the primary US manufacturer (a legacy of Thiokol Corporation → Cordant Technologies → Alliant Techsystems → Orbital ATK → Northrop Grumman).
- Aerojet Rocketdyne (now under L3Harris) — also a leading US producer.
- The Holston Army Ammunition Plant in Tennessee (run by BAE Systems) is the main US Army explosive production site.
Taiwan
- Chungshan Institute of Science and Technology (CIST) — inaugurated a CL-20 production facility in 2022, with integration into the Hsiung Feng II and Hsiung Feng III missile lines.
India
- DRDO's High Energy Materials Research Laboratory (HEMRL) in Pune synthesized CL-20 (called "ICL-20"), with ~100 kg produced in collaboration with Premier Explosives Limited (PEL) in Andhra Pradesh.
In short,
China is the only country with proven large-scale industrial production, while the
US relies on
Northrop Grumman and
L3Harris for limited domestic supply.