The values of speed and endurance can vary considerably between the design, as built and service states due to various factors, which usually have an adverse affect e.g. changes and additions in underwater and topside fittings, increase in displacement, carrying additional fuel above the normal design stowage, the states of the sea and the vessel's bottom.
The design figures are based on the vessel being at the design displacement with a clean bottom in calm seas. The service figures have been assessed as far as possible as those likely to have been achieved soon after going into service when carrying the normal stowage of oil fuel, with a moderately clean bottom in reasonably calm seas.
For convenience the classes are divided into two sections IIIA and IIIB to cover:
WHEN USING FIGURES FROM THESE APPENDICES IT IS ADVISABLE TO CONSULT THE RELEVANT CLASS CHAPTER FOR CLARIFICATION
This form is for you to comment on, or add additional information to this page. Any questions will be deleted. If you wish to ask a question contact the Branch or the Webmaster using the Contact Us page or ask your question on our Facebook Page