What is a primary indication of power output on the turboprop engine?

• A. torque
• B. RPM
• C. EGT
• D. fuel flow

Answer: (A)

In a turboprop, the most direct indicator of how much power the engine is delivering to the propeller is the torque on the reduction gear. Torque represents the turning force the engine is actually applying to drive the propeller, so it tells you the engine’s current power output more accurately than other indicators. The propeller is held at a commanded RPM by the governor, so RPM can stay near a set value even as the torque (and thus power) changes with loading and altitude. EGT shows turbine inlet temperature and is a health/limit indicator, not a direct measure of power. Fuel flow indicates how much fuel is being burned, which correlates with power but isn’t a direct readout of the actual power being produced. So torque is the best, most immediate cue to the engine’s power output.