II SEAMNSHIP

• SHIP'S DIMENSION
• After Perpendicular (AP): A perpendicular drawn to the waterline at the point where the aft side of the rudder post meets the summer load line. Where no rudder post is fitted it is

  taken as the centre line of the rudder stock.
• Forward Perpendicular (FP): A perpendicular drawn to the waterline at the point where the

  foreside of the stem meets the summer load line.
• Length Between Perpendiculars (LBP): The length between the forward and aft

  perpendiculars measured along the summer load line.
• Amidships: A point midway between the after and forward perpendiculars.
• Length Overall (LOA): Length of vessel taken over all extremities.
• Length on the Waterline (LWL)- the term denotes the length of the vessel at the point

  where it sits in the water.
• Base Line: A horizontal line drawn at the top of the keel plate. All vertical moulded dimensions are measured relative to this line.
• Moulded Beam: Measured at the midship section is the maximum moulded breadth of the ship.
• Moulded Draft: Measured from the base line to the summer load line at the midship section.
• Moulded Depth: Measured from the base line to the heel of the upper deck beam at the ship’s side amidships.
• Extreme Beam: The maximum beam taken over all extremities.
• Extreme Draft: Taken from the lowest point of keel to the summer load line. Draft marks represent extreme drafts.
• Extreme Depth: Depth of vessel at ship’s side from upper deck to lowest point of keel.
• Freeboard: The vertical distance measured at the ship’s side between the summer load line(or service draft) and the freeboard deck.
• Air draft: is the distance from the surface of the water to the highest point on a vessel.
• Tumblehome: The inward curvature of the side shell above the summer load line.
• Camber (or Round of Beam): Curvature of decks in the transverse direction.
• Rise of Floor (or Deadrise): The rise of the bottom shell plating line above the base line. This rise is measured at the line of moulded beam.
• Camber Measured as the height of deck at centre above the height of deck at side.
• Half Siding of Keel: The horizontal flat portion of the bottom shell measured to port or starboard of the ship’s longitudinal centre line. This is a useful dimension to know when dry-docking.
• Sheer: Curvature of decks in the longitudinal direction. Measured as the height of deck at side at any point above the height of deck at side amidships.
• Flare: The outward curvature of the side shell above the waterline. It promotes dryness and is therefore associated with the fore end of ship.
• Stem Rake: Inclination of the stem line from the vertical.
• Keel Rake: Inclination of the keel line from the horizontal.
• Tween Deck Height: Vertical distance between adjacent decks measured from the tops of deck beams at ships side.
• Parallel Middle Body: The length over which the amidship section remains constant in area and shape.
• Run: The immersed body of the vessel aft of the parallelmiddle body.
• Tonnage: This is often referred to when the size of the vessel is discussed, and the gross tonnage is quoted from Lloyds Register. Tonnage is a measure of the enclosed internal volume of the vessel
• Lightweight: is the weight of vessel as built, including boiler water, lubricating oil, and cooling water system.
• Entrance: The immersed body of the vessel forward of the parallel middle body.
• Deadweight: is the difference between the lightweight and loaded displacement, i.e. it is the weight of cargo plus weights of fuel, stores, water ballast, fresh water, crew and passengers, and baggage.
• Displacement: is made up of lightweight plus deadweight.
• TEU and FEU: Indicate the cargo carrying capacity of container ships. TEU (twenty foot equivalent unit) indicates the number of standard shipping containers that may be carried On some shipping routes container ships may carry standard containers that are 40 feet in length. FEU is forty foot equivalent unit.