On the marine gas turbine shown in the illustration, the gas generator speed sensor is located where? Illustration GT-0017

Correct Answer: Option B — On the accessory gearbox.

The gas generator speed sensor is mounted on the accessory gearbox, which is driven by the gas generator rotor. By measuring the rotational speed at this location, the control system receives accurate data regarding the gas generator's performance, which is vital for governing and engine protection logic.