What is the function of the Power Turbine?

• A. Drives fuel pump
• B. Transforms gas energy into mechanical power to drive the reduction gearbox
• C. Compresses intake air
• D. Provides lubrication to bearings

Answer: (B)

The main idea is that the power turbine harvests energy from the expanding hot gases and turns it into useful shaft power. That shaft power is routed through the reduction gearbox to spin the propeller or output shaft at the lower speed and higher torque needed for propulsion. In other words, the turbine’s job is to convert gas energy into mechanical power that drives the gearbox and ultimately the load.

This isn’t about compressing intake air—that’s the job of the compressor. It isn’t about lubricating bearings—that’s handled by the lubrication system. And while some engine accessories can be driven by an accessory gear train, the power turbine’s specific role is to provide that shaft power to the gearbox for propulsion.