Why are the diameters of propeller of Cessna 152 given as 67.5 to 69.0 inches?

The diameters of the propeller for the Cessna 152 are specified as 67.5 to 69.0 inches to optimize performance characteristics such as thrust, efficiency, and climb rate. This range ensures that the propeller can effectively convert engine power into forward motion while maintaining appropriate aerodynamic properties. Additionally, the specified diameter helps ensure compatibility with the aircraft's design and operational limits, ensuring safety and reliability during flight.