Different Methods of Refloating a Ship

Abstract

In the shipping industry it is vital for a ships construction to take into consideration any grounding event that might occur, due to the fact that grounding has been representing an important issue in the maritime industry being almost always connected to a catastrophic pollution of the marine environment. Another important matter it is represented by the refloating methods that should be applied on these ships that are grounded, in order to safely take them out of their position with minimum hull damage and no pollution to the marine environment. There is a need for a basic understanding of the geometry, stability and strength of intact ships before trying to refloat a damaged, grounded or sunken ship. When talking about refloating a grounded ship, it is first of all necessary to fully understand the grounded event that led the ship into that position so that the best method for refloating to be applied. It is an important demand to establish the appropriate method of refloating so that the risk of polluting to be reduced at minimum. It is really vital to have a well thought-out and organized salvage plan in order to apply a certain refloating operation. In order to have such a salvage plan it is necessary to investigate properly the ships site and gather the appropriate information. Operational conditions around the ships site, namely the casualty, are dynamic and may change several times throughout the course of the refloating operation and this way many of the refloating operations cannot be applied on that certain cases of grounding. Ships groundings can have devastating effects on the marine environment. Cleaning up after a major grounding event could lead to enormous amounts of money and even then there is no certainty that the cleaning process has the best results or even the wanted ones. The general opinion of the shipping industry is that the cheapest method to refloat a grounded ship is to use the means present onboard that particular ship (means of propulsion, rudder, ballasting/de-ballasting operations, getting rid of weights). In this paper I tried to show how a ship can or cannot use the means present onboard in order to put herself out of the grounding position. In order to do that I have used Transas Navi Trainer 5000 simulator.