🔍 Key Concepts

• Turning gear purpose – why engines use a turning (jacking) gear and what parts it connects to • Propeller shaft condition – what must be true about the main shaft before you mechanically connect a small turning mechanism to it • Risk of damage – what could happen if the main engine or shaft is still moving when the turning gear is engaged

💭 Think About

• Think about what the turning gear actually drives: is it meant to move a running engine or a stopped engine very slowly? • Which choice describes a condition that directly protects the small, delicate turning gear from being over‑speeded or shock‑loaded? • Which options talk about signals or other equipment that don’t necessarily guarantee the main shaft is completely motionless?

✅ Before You Answer

• Verify which option clearly ensures the main shaft/propeller is completely stopped and cannot rotate freely before engagement. • Check which answer directly relates to mechanical protection of the turning gear teeth, clutch, or pinion, not just to control-room signals. • Eliminate any options that could still allow residual rotation or unexpected movement of the main engine shaft while engaging the turning gear.