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Bloomfield, CT

Developing patented multi-fuel rotary engine power systems and maturing compact mobile command post auxiliary power units to unlock Army SBIR CATALYST matching funding.

• HEHC Rotary Engine Platform: LiquidPiston develops rotary engines built on the High Efficiency Hybrid Cycle (HEHC) and the X-Engine architecture, using a compact rotor and eccentric shaft for higher power density.
• High Efficiency and Reduced Complexity: The X-Engine architecture is designed around a rotary configuration with only two primary moving parts, targeting efficiency and operational simplicity for demanding environments.
• Multi-Fuel Capability: The engine platform supports multi-fuel operation including diesel and jet fuel, and it is compatible with hybrid-electric power configurations for defense and aerospace use cases.
• MASCP Auxiliary Power Development: The raise is aimed at developing and maturing compact mobile command post auxiliary power units and related systems under the Army’s Mobile and Survivable Command Post (MASCP) initiative.
• Expanded Test and Manufacturing Capacity: Proceeds support renovation of a new headquarters and integrated laboratory and manufacturing facility in Suffield, Connecticut, to expand testing capacity and in-house machining capability.

LiquidPiston is raising funds to support the development and maturation of compact mobile command post auxiliary power units and related systems under the Army’s Mobile and Survivable Command Post (MASCP) initiative. The campaign is intended to provide matching capital to unlock additional non-dilutive Army SBIR CATALYST funding, contingent on commitments from an Army transition partner and an industrial integrator.

The company develops advanced rotary engines based on the High Efficiency Hybrid Cycle (HEHC) and the X-Engine architecture, designed to deliver higher power density with a compact rotor and eccentric shaft and a reduced moving-parts count. LiquidPiston positions the engines for defense, aerospace, and industrial power systems, emphasizing multi-fuel capability across fuels such as diesel and jet fuel, and compatibility with hybrid-electric power configurations. With a portfolio of 110+ granted and pending patents, including patents covering the HEHC thermodynamic cycle and enabling technologies, LiquidPiston works on industrialization and commercialization through licensing and engineering services. Proceeds also support renovation and buildout of a new headquarters and integrated laboratory and manufacturing facility in Suffield, Connecticut, including specialized testing equipment, dynamometers, and in-house machining capacity to increase development and production throughput. Additional allocations cover marketing and program management activities needed for defense customer engagement, documentation, and readiness for prototype field testing.

Company Info

LiquidPiston develops and licenses compact, multi-fuel rotary combustion engines and hybrid power systems for defense, aerospace, and industrial customers.

LiquidPiston develops compact rotary combustion engines based on a patented high-efficiency hybrid cycle and an X-Engine architecture designed to reduce size, weight, and mechanical complexity. The engine platform uses a rotor and eccentric shaft as the two primary moving parts and supports high-compression, constant-volume combustion concepts aimed at improving power density and efficiency.

The company applies its technology across defense, aerospace, and industrial power needs, including multi-fuel operation on diesel, jet fuel, biofuels, propane, and hydrogen. LiquidPiston also builds and integrates hybrid electric power configurations and portable auxiliary power systems, enabling roles such as mobile command post power generation and unmanned aerial system propulsion support.