How is propulsion efficiency defined in turbine engines?

Propulsion efficiency in turbine engines is defined as the ratio of thrust output to the energy input provided by the fuel. This measure helps to evaluate how effectively an engine converts the energy from fuel into useful thrust. A higher ratio indicates that a larger portion of the energy is being converted into thrust, which is essential for the performance and efficiency of an aircraft.

Understanding propulsion efficiency is critical for optimizing fuel consumption and enhancing overall engine performance. This concept directly relates to how well an engine operates; an engine with high propulsion efficiency delivers more thrust for the same amount of fuel compared to one with lower efficiency. Hence, it is a key indicator of an engine's effectiveness in terms of navigating the trade-offs between thrust, fuel consumption, and overall operational capability.