Comments by "Gort" (@gort8203) on "Jet Engine Fixes + Help me Decide on Something" video.

  1. The discussion of pressure within the engine was a bit unclear to me. If it helps, a turbojet creates thrust by increasing the velocity of the exhaust, but there is also a pressure difference between the air entering the compressor and exiting the turbine. The maximum engine pressure ration (EPR) an engine is capable of is an indicator of its efficiency. For a turbojet the actual EPR indicated at any given moment is the primary method of setting engine thrust to the value desired for takeoff or climb. Turbofan engines are different and typical set thrust by the fan RPM (N1) because much or most of the fan air bypasses the turbine, making pressure ratio a less useful indication of thrust setting.
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