🔍 Key Concepts

• Cross-compound turbine layout (how HP and LP turbines are arranged on separate shafts) • Where the astern turbine is usually placed in relation to the main propulsion turbine stages • Function of a cruising turbine versus main/astern turbines

💭 Think About

• In a cross-compound set, think about which turbine handles normal ahead power and which one is associated with reversing the shaft rotation. • Ask yourself: when the ship needs to go astern, which part of the turbine train must be engaged quickly and is commonly mounted on the same shaft as which main element? • Consider: is a cruising turbine normally placed on the same shaft as the high‑pressure or low‑pressure turbine, and is it typically at the ‘end’ of the rotor?

✅ Before You Answer

• Identify which turbine in the options is specifically used for reversing (astern) power. • Recall whether a high-pressure turbine would logically be located at the end of a low-pressure turbine rotor in a cross‑compound setup. • Verify in your notes/diagrams how ahead and astern turbines are grouped on each shaft in a cross‑compound marine turbine plant.