Outline a normal shutdown sequence for a gas turbine.

• A. Reduce power to idle, place fuel control to shutdown, monitor oil pressure/EGT during spool-down, secure fuel and electrical power, lockout if required.
• B. Immediately cut fuel and disconnect all systems.
• C. Increase load and then shut down.
• D. No specific sequence; just cut power.

Answer: (A)

Controlled shutdown of a gas turbine aims to decelerate smoothly and bring the machine to a safe stop while protecting bearings, seals, and hot sections. Start by reducing power to idle so the rotor slows gradually rather than stopping abruptly, which minimizes thermal and mechanical stresses. Then place the fuel control to shutdown to terminate fuel flow in a controlled manner, avoiding sudden temperature swings. As the turbine decelerates, monitor oil pressure and exhaust gas temperature to ensure lubrication remains adequate and temperatures trend down; if oil pressure drops or EGT behaves abnormally, you can reassess the shutdown process. Once conditions look safe and the rotor is near idle, secure fuel and electrical power to prevent unintended re-ignition, and apply lockout if required by procedure to prevent restart during maintenance or after a fault. This sequence protects the turbine and attached systems and provides a verified safe shutdown.