#propulsion systems

• Jet engine — An air-breathing jet engine (reactive) that utilizes surrounding air as an oxidizer for burning fuel and generating propulsion force through the rapid expulsion of exhaust gases. Unlike rocket engines, this structural mechanical assembly fully depends on the presence of Earth's atmosphere to function, being widely used in modern airliners and supersonic aircraft.
• To self-propel — To propel oneself or move a vehicle or body by its own energetic and motor means, structurally integrated within it, without relying on an external pulling or pushing force. In transportation and aerospace engineering, it describes the ability of a device, vehicle, or projectile to generate the force required for travel by consuming a fuel or energy source stored on board.
• Self-propulsion — The act of self-propelling and its result; a technical or mechanical process through which a vehicle, projectile, or body generates its force of motion and spatial displacement utilizing an internal energy source or its own engine, without the input of an external pulling or pushing force. This structural system is fundamental in the design of rockets, spacecraft, submarines, and heavy self-propelled machinery, optimizing the operational independence of the assembly.