Titan makes 1st refloat attempt on 3rd February
(with thanks to Richard Grundy of www.tristandc.com)
The salvage team made a first attempt on Saturday 3 February to refloat the oil rig stranded at Trypot Bay. However, although there was plenty of buoyancy on the port side of the rig, the tides were not sufficient to lift the starboard side clear of the reef.
The main attempt to refloat is still scheduled for mid-February, and the team will be working hard until then to regain some more of the buoyancy they need.
The photographs (first two) show clearly (compared with the situation in December – photo at the end) how much of the structure has been cut away to remove weight to assist the salvage attempt and the amount of buoyancy obtained, particularly on the seaward size of the rig, where the previous waterline mark shows how much further the support columns have lifted out of the water.
Pressure Tides and Winds
The Titan salvage team will be aware that during anticyclonic weather and the accompanying high pressure, sea levels are lowered by the increased weight of air – about 1cm for every mb of increased pressure. So it is not only the high tide on 18th February, but the air pressure, which will determine the exact level of the ocean. Ironically it would be better to be lower pressure (with the likelihood of stronger winds) rather than a calm anticyclone which could raise the high tide by a crucial few extra centimetres. Perfect would be low pressure with a north-west wind (the prevailing wind on Tristan) so that Trypot Bay would be in the lee.
It’s an ill wind……. (note from Web Manager Richard Grundy)