🔍 Key Concepts

• Single-shaft vs split-shaft gas turbine layout (how power turbine and compressor are connected) • How starting torque and reversing are usually handled in marine gas turbine installations • Relationship between number of shafts/gears and mechanical complexity (moving parts)

💭 Think About

• Think about how the compressor and turbine are connected in a single-shaft design. Does this tend to make the machinery simpler or more complex than a split-shaft? • In most marine gas turbine plants, how is reverse thrust or reverse propulsion actually achieved—inside the turbine itself, or by some other component? • Which design is more likely to have higher starting torque at low RPM, where the turbine is just coming up to speed?

✅ Before You Answer

• Be clear on which option describes mechanical simplicity (how many separate turbine sections, shafts, and couplings are involved). • Ask yourself whether gas turbines are normally directly reversible like some diesel engines, or if they rely on a reduction/reversing gear or controllable-pitch propeller. • Eliminate any choice that conflicts with the typical complexity advantage of a single-shaft layout versus a split-shaft layout.