Which of the following best describes a characteristic of the propulsion reduction gear?

Which of the following best describes a characteristic of the propulsion reduction gear?

• A. It Increases The Speed Of The Turbines
• B. It Reduces The High Speed Output Of The Turbines
• C. It Stores Energy
• D. It Cools The Oil

Answer: (B)

Propulsion reduction gear serves to lower the turbine’s high shaft speed to a much slower, more usable speed for the propeller while increasing torque. Turbines run at very high RPM for efficiency, but the propeller needs slower rotation to avoid overspeed, cavitation, and excessive wear. The gear ratio in the reduction gear accomplishes this speed reduction, making the statement that it reduces the high speed output of the turbines the correct description. It isn’t about storing energy, cooling oil, or increasing turbine speed, which are not the functions of the reduction gear.

Propulsion reduction gear serves to lower the turbine’s high shaft speed to a much slower, more usable speed for the propeller while increasing torque. Turbines run at very high RPM for efficiency, but the propeller needs slower rotation to avoid overspeed, cavitation, and excessive wear. The gear ratio in the reduction gear accomplishes this speed reduction, making the statement that it reduces the high speed output of the turbines the correct description. It isn’t about storing energy, cooling oil, or increasing turbine speed, which are not the functions of the reduction gear.