Space MIAD Practice Test 2025 – 400 Free Practice Questions to Pass the Exam

The use of hydrazine in spacecraft propulsion primarily falls under monopropellant propulsion. This type of propulsion system utilizes a single chemical propellant, which, when heated or catalyzed, produces thrust through the rapid expulsion of gas. Hydrazine is commonly preferred because of its high energy density and reliability.

In monopropellant systems, hydrazine decomposes upon contact with a catalyst, generating hot gases that provide thrust. This process is straightforward and allows for precise control, making it ideal for spacecraft maneuvering and attitude control. It simplifies the design and operation compared to systems that require multiple propellants, which often involve more complex management and handling procedures.

While other types of propulsion, like solid or hybrid, do serve various purposes in the aerospace industry, they do not utilize hydrazine in the same manner as monopropellant systems do. Solid rocket propulsion typically involves a solid fuel that has oxidizers mixed in, and hybrid propulsion combines solid fuel with a liquid oxidizer, neither of which aligns with the characteristics of hydrazine usage. Bipropellant propulsion involves two different substances (fuel and oxidizer) and is not specific to the single propellant nature of hydrazine. Thus, monopropellant propulsion is the correct