Bottom raking damage in tanker design
Bottom raking damage: the long grounding damage assumed by MARPOL Annex I Regulation 28.7 for oil tankers of 20,000 dwt and above, and its use in other rules.
Bottom raking damage is the assumed long, shallow breach of a ship’s bottom from a grounding at speed. In MARPOL Annex I it appears in Regulation 28.7 , which applies to oil tankers of 20,000 tonnes deadweight and above delivered on or after 6 July 1996: the damage runs 0.6L from the forward perpendicular for tankers of 75,000 dwt and above and 0.4L below that, B/3 wide anywhere in the bottom, and breaches the outer hull.
The full article will set out how the raking case differs from the local bottom damage of Regulation 28.2.2, how it interacts with the double bottom height of Regulation 19 , and the paragraph’s renumbering from 28.6 to 28.7 on 1 January 2016.