UMC International recently carried out the repair of a stabiliser fin of a luxury 55m yacht moored in the Dutch Caribbean Island of Curacao.
The starboard stabiliser fin had sustained some damage and the vessel was not able to sail in its present condition. A modified but tried and tested UMC procedure that has been approved by the MOD to remove stabilisers afloat was put forward to the client and Fraser Yachts.
Upon approval from the customer UMC immediately despatched their fly-away team of specialist marine architects and diving supervisor to project manage the removal process. Associates of UMC’s global network of diving partners, Miami Divers, were available to provide local support in the way of additional equipment and divers.
Because the removal was being undertaken as an afloat process, UMC had to adapt the original OEM removal process to ensure the watertight integrity of the vessel. The “KoopNautic SR4080” design fin was secured outboard by way of underwater welt welding lifting eyes to the hull and to the fin itself. The fin was then restrained with lifting strops and rigging to the external hull. Once the fin was secure outboard the internal components were dismantled as per the OEM removal process and all of the components were removed.
Dave Richards, Project Manager and Director said, “During the removal it was noticed that the tiller arm and “Dobikon” clamping element were not budging so we contacted the OEM who advised us to manufacture a second jacking plate to allow double the jacking pressure.”
He continued, “Due to local support and knowledge, the plate was manufactured locally as per the OEM drawings. However, this still did not free the clamping element or tiller arm and after some concerted ideas and effort, we asked the owners if we could cut a section out the tiller arm, and this finally released the components.”
An internal cofferdam was then bolted in position and the stabiliser fin lowered and transferred to a 6T lift bag and towed to the bow of the vessel where it was lifted clear of the water and then secured to the deck. The stabiliser shaft housing was then blanked off with a 15mm steel plate filled and covered with underwater epoxy filler.
The removal of the damaged stab fin carried out by UMC whilst the vessel was still afloat, saved time and considerable expenses and allowed the yacht to go directly to drydock for a full stabiliser fin repair.