Because of hydrazine's carcinogenic and toxic nature its use in space propulsion is expensive and may lead to significant delays. One already established alternative is to use energetic salt-based ionic liquid propellants, dissolving ammonium dinitramide or hydroxyl ammonium nitrate in water with additives. However, with this approach costs remain high because these substances are quite costly and highly regulated due to their partly unstable and energetic nature. Nitromethane, being a widely available solvent, offers a cost-effective solution, with comparable propulsive performance. In this paper results of a hot-fire test campaign are presented. Stable combustion using NMP-001 a nitromethane-based monopropellant at 15 to 40 bar pressure at 84 to 94 % C*-efficiency in a combustion chamber with L* = 9 to 11.7 m was demonstrated