I ask Chat GPT an engineering question

dbp:

Modern propeller driven aircraft normally operate at 1500 to 2700 rpm. At this rpm, the engine can only develop about half of its theoretical power. In theory, a smaller engine could be used, if a way could be found to run at higher rpm. This would save weight. A ducted fan could be used instead of a propeller but would the weight savings in the engine be lost to the heavier ducted fan? Chat:

Running an engine at higher RPMs may require significant changes to the design and materials of the engine components to withstand the increased stresses and forces. This could potentially offset any weight savings achieved by using a smaller engine.

Higher RPMs might lead to increased aerodynamic drag on the propeller or fan blades. This could affect the overall efficiency and performance of the aircraft.

Higher RPMs often result in increased noise and vibration. This can have implications for passenger comfort, as well as structural considerations for the aircraft.

Ducted Fan Considerations:>While a ducted fan might offer some advantages in terms of efficiency and noise reduction, the weight of the ducted fan system itself could offset any weight savings from using a smaller, higher RPM engine.

Technology and Material Limitations:>The current state of technology and materials might impose limitations on designing engines that can efficiently operate at extremely high RPMs without compromising reliability and safety.

In practice, aircraft designers carefully balance various factors, including weight, efficiency, safety, and operational considerations, to determine the optimal engine and propeller or fan configuration for a given aircraft. While it's always possible that future technological advancements could lead to new possibilities, any significant departure from the current designs would require thorough testing and validation to ensure safety and performance.>It's also worth noting that different aircraft have different requirements, and what works well for one type of aircraft may not be suitable for another.