Lesson 1 of 8 · 1 min
Hull Structure — The Terms You Must Own
The examiner uses construction terms without explaining them, and expects you to do the same. This is the working vocabulary:
| Term | Meaning |
|---|---|
| Keel | The backbone — the principal fore-and-aft strength member along the bottom centreline |
| Frames | Transverse ribs rising from the keel, giving the hull its shape and transverse strength |
| Stringers / girders | Longitudinal members tying the frames together — longitudinal strength |
| Beams | Transverse members supporting the decks, tying the two sides of the hull together |
| Bulkheads | Vertical partitions — structural, fire (class divisions), or watertight subdivision |
| Stem / stern post | The forward and after extensions of the keel structure |
| Garboard strake | The plating strake next to the keel |
| Sheer strake | The uppermost side strake at deck edge — highly stressed; why cuts and welds there matter |
| Sheer | The fore-and-aft curve of the deck line, rising toward the ends |
| Camber | The transverse curve of the deck, shedding water to the sides |
| Bilge keel | External longitudinal fins at the turn of the bilge — roll damping |
| Double bottom | Inner and outer bottom plating forming tanks — grounding protection, ballast/fuel stowage, and LOW weight |
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Hull labeller
Name the structure on the drawing.
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Definitions trainer
The ship-knowledge terms the examiner expects you to own.
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