Safinah Head of PT & ES, Keith Hutchinson presents "Tanker Damage Stability – Historical Problems, Solutions and Outstanding Issues" to RINA, Tuesday 25th April 2019 at Lloyds Register of Shipping, London, United Kingdom
This presentation will discuss an issue of some concern over recent years amongst regulators and operators as to how best to demonstrate compliance with the tanker damage stability regulations if a specific loading condition deviates significantly from those shown in the approved Stability Information Book / Trim and Stability Book.
Presentation Abstract
This presentation will discuss an issue of some concern over recent years amongst regulators and operators as to how best to demonstrate compliance with the tanker damage stability regulations if a specific loading condition deviates significantly from those shown in the approved Stability Information Book / Trim and Stability Book. Some of the regulations state that if a loading condition does differ significantly then it must be approved by the authorities for compliance with the damage stability regulations before the vessel sails. Complications arise through having to calculate fluid loss from a damaged compartment which may be filled to any level and carry liquids with a wide potential range of specific gravity. When this is allied to an extensive variety of loading patterns and multi-compartment side or bottom / raking damages, demonstration of compliance other than by use of an on-board ‘direct calculation’ computer can be problematic even though the regulations permit the simplifying assumption that all the fluid in the damaged compartment is instantaneously lost and replaced by seawater up to the outside damaged equilibrium waterline. In practice, for various reasons, advance approval of all the potential damage scenarios for ‘non-standard’ loading conditions is seldom sought and hence it was widely acknowledged that there was an urgent need to develop guidelines for the verification of damage stability requirements for tankers that regularly sail in conditions of loading significantly different from those in approved documentation. Such guidelines have recently been developed by the International Maritime Organisation (IMO) and the UK’s Maritime and Coastguard Agency (MCA). This presentation discusses these issues, from the aspects of the ship designer, regulators and operators, and proposes practical and effective solutions.
