Development and Qualification of a CubeSat Scale Hybrid Thruster for In-Orbit Demonstration

The growing demand for agile orbital maneuvering in small satellites highlights the need for propulsion systems that provide both sufficient ΔV and meaningful thrust. Existing options remain polarized between low‑thrust electric propulsion and hazardous, difficult‑to‑miniaturize chemical systems. Hybrid chemical propulsion offers a promising middle ground; however, only one in‑orbit demonstration has ever been conducted, leaving the technology at a low level of maturity. Letara Ltd. has developed ICR‑X, a 2U CubeSat‑class hybrid chemical propulsion system using HDPE fuel and nitrous oxide. The system features an integrated oxidizer‑tank–combustion‑chamber structure, a low‑power multi‑restart ECP ignition system, and oxidizer‑temperature‑based thrust control, enabling 1–4 N of thrust and approximately 45 N·s of total impulse. Extensive ground testing—including atmospheric and reduced‑pressure combustion tests—confirmed reliable ignition and stable 5‑second burns under both gas‑phase‑dominant and liquid‑phase‑dominant oxidizer supply conditions. Environmental qualification tests (vibration, TVAC, EMI/EMC) further verified readiness for spaceflight. In the upcoming in‑orbit mission, multiple burns will be conducted to evaluate ignition feasibility, combustion stability, and repeatability in space. ICR‑X will serve as the world’s first in‑orbit demonstration of a CubeSat‑sized hybrid chemical thruster, and aim to further achieve multiple ignition events, marking a significant step toward practical hybrid propulsion for small satellites.