The device that reduces the power turbine RPM and transfers power to the power output flange is the:

• A. Turbine governor
• B. Fuel control unit
• C. Combustion chamber
• D. Reduction gearbox

Answer: (D)

The main idea is that the device lowers the turbine’s very high rotational speed and puts the resulting power onto the output shaft. In a gas turbine, the power turbine spins incredibly fast, so a reduction gearbox steps the speed down to a practical, usable level while increasing torque. This lets the power be transferred efficiently to the power output flange and any connected equipment, like a generator, without forcing the output to run at extreme RPMs. The other components play different roles: the turbine governor keeps speed within limits by adjusting fuel, the fuel control unit meters fuel, and the combustion chamber creates the hot gases that drive the turbine. None of these directly reduce RPM and transfer power to the output shaft the way a reduction gearbox does.