Accidents involving commercial ships have serious cost and environmental implications and are not rare. Between January 1992 and March 1999 a total of 593 merchant ships were lost. In many of these cases, if a support tool had been available there was quite a good probability that the accident would have been avoided. For instance, in the AMOCO CADIZ accident, if action had been taken early enough to control the drift this would have prevented the grounding of the ship and the spilling of 227 000 tons of crude oil, with a cost of about €282 million.
The overall objective of SAFETOW was to provide masters of ships with tools to help them control their vessels if they become disabled and provide masters of salvage and escort tugs with tools which will enable them to take decisions in real-time with the best available information regarding the consequence of their actions.
SAFETOW built on innovative technologies to develop easily parameterisable modular solutions for
- a manoeuvring aid;
- a towing aid; and
- a lines monitor.
The manoeuvring aid is aimed at tankers and advises the disabled ship on the likely results of any manoeuvre (or the lack of it). Even when a ship is disabled there are a few options for action available to it which will have an effect on the way it is drifting. It is, however, essential to forecast accurately the consequences of any such action so as to be sure of taking the appropriate decision. The manoeuvring model will be able to predict the drift mode accurately and will also make suggestions about the most advisable course of action.
The towing aid is aimed at the escort and salvage tugs. It will have a full model of the tug plus configurable and easily parameterisable models of the towed vessel and other involved tugs. This will allow the manoeuvring model of the whole tug plus the disabled tanker system to be put together in real time out of pre-existing models and a few basic parameters.
The lines monitor will assist the tug crews in determining whether the towing equipment is being stressed, which is usually a cause for concern in the towing configuration.
The project yielded the following results:
- definition of a full set of requirements for SAFETOW systems;
- definition of a full set of specifications for SAFETOW systems;
- implementation of a first set of prototypes;
- evaluation of a first set of prototypes;
- revised set of specifications for SAFETOW system;
- final implementation of the revised SAFETOW system;
- end-user evaluations of the final prototypes.