THE EVALUATION OF LIFEBOAT FORWARD VELOCITY CAPABILITY SUBJECT TO EXTREME CONDITIONS AT THE OFFSHORE INSTALLATIONS

Year 2020, Issue: 19, 31 - 40, 16.09.2020

Özgür Özgüç

Abstract

For the offshore installations, dropping lifeboats are employed as a last reserve evacuation method. Lifeboats normally rest on the skid, which is mounted on the mother vessel, until the hook holding the lifeboat rests. It is important that lifeboat diving is a safe method of evacuation. This study describes the capability assessment with respect to the forward speed of the lifeboats under extreme storm conditions. Hence, the aim of the analysis is to determine the limiting storm conditions where the lifeboats are still able to maneuverer away from the offshore installation. The findings of this work are in accordance with the simplified methods, where the North Sea is considered as the suitability of lifeboats under extreme storm conditions. The findings show that the lifeboats cannot propagate forward in storm conditions where the
significant wave height is larger than 11 m. In addition, the net forward force for sea states with wave heights of 10 m and 11 m is rather small and hence the lifeboats may not be able to propagate forward with sufficient velocity.

Keywords

lifeboat, offshore installation, wind force, storm condition, North Sea

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