🔍 Key Concepts

• Think about how a single-screw (one propeller shaft) is normally aligned in a vessel: usually on or very near the centerline for balance and efficiency. • Consider where it is safest and most practical to route piping in relation to moving machinery like a rotating shaft and where crew need to walk for inspection. • Visualize a shaft tunnel cross-section: shaft in the middle or off to one side, then ask yourself where walkways and piping would logically go to allow access and protection.

💭 Think About

• On a single-screw ship, would the shaft and its tunnel more likely be on the centerline or offset? Why would designers choose that arrangement? • For crew access and maintenance, is it more practical to have walkways on both sides of the shaft or just one side? How does this affect safety and inspection? • Would running piping overhead above a rotating shaft or under protected walkways be better for protection from damage and ease of support and drainage?

✅ Before You Answer

• Focus first on single-screw = alignment: confirm in your mind whether that usually means centerline or offset for the shaft tunnel. • Check which options place walkways in a way that allows safe inspection along the whole tunnel without climbing over or reaching around the shaft. • Check which options put piping in the most protected and structurally convenient area (overhead vs. under walkways) while keeping clear of the rotating shaft.