Main Page | See live article | Alphabetical index A hybrid propulsion system is composed of solid fuel and liquid or gas oxidizer, typically. These systems are superior to [[solid rocket|solid propulsion systems]] in the respects of safety, throttling, restartability, stability, and environmental cleanliness. Hybrid systems are more complex than solids, though, and consequently typically heavier and more expensive. See also: Spacecraft propulsion, rocketry This article is from Wikipedia. All text is available under the terms of the GNU Free Documentation License.