A stern winch capable of lifting 28 tonnes has been welded to the deck of the Seaworks vessel Brandywine in preparation for this week's Aratere propeller lifting mission from the bottom of Cook Strait.
Seaworks chief executive Steve Macintyre said weather and tide patterns were shaping up well for an attempt to lift the propeller from 123 metres of water, out from the entrance to Tory Channel, later this week.
The stern winch on the Brandywine, a former United States tank carrier, would work in conjunction with another Seaworks vessel, the Seasurveyor, which will be the command centre for the remote controlled SC58 submarine required for stropping work in the salvage operation.
Mr Macintyre said the first priority would be to get the submarine into a position to strop the 6.5 tonne propeller and broken shaft.
This would be done by using a number of chains lowered from Brandywine's winch.
There were no guarantees the propeller salvage lift would succeed but if the propeller could be lifted the object of the exercise would then be to tuck it underneath Brandywine's hull.and transport it back to shallower waters.
Mr Macintyre conceded the location of the Cook Strait cable might mean problems ferrying the propeller back to Wellington above the cable.
"The propeller is sitting at 45 degrees on the seabed. The lift will be a tricky operation. There are no guarantees in all of this," Mr Macintyre said.
Skilled pilots would operate the remotely controlled submarine during the multi-chain stropping operation.
He agreed with an earlier statement made by an InterIslander spokesman that the propeller lifting operation would be attempted between Tuesday and Saturday this week.
"Tide and weather conditions are looking good. We have to be flexible in our planning for this job," Mr Macintyre said.
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