Salvage science - making our world
The Kiperousa held in position by the Nikolay Chiker. Photo © Dr Jim Cambray
As an example, salvors have worked hard to 'keep the pollution on the ship' with the result that improvements in technology have reduced the number of serious oil spills from an average of 24 per year in the 70's to 5 in 2004.
Ships and their cargoes are very expensive things. In the case of vessels that carry cargo (e.g. oil tankers) or components (e.g. nuclear reactors powering submarines) that are of great environmental danger, the potential damage to the environment if the vessel sinks may be much greater than the value of the items in transit themselves. To protect the owners against all losses, vessels are insured. When something goes wrong, it is in the interests of all parties involved that the financial, environmental and public relations losses are kept to a minimum. Salvage operators are contracted to save ships, cargo, the environment and corporate image.
When a ship has an accident, various legal options are rapidly explored. A salvage contract is signed and the salvors begin their work. The head of the salvage operation is the Salvage Master. This individual supervises maritime architects and engineers who assess the damage to the ship. These experts work with specialised divers to survey the ship and work out ways to stabilise it. In many cases these experts arrive at the machine before any big machinery is brought in.
Once the situation is understood, the appropriate machinery is mobilised to the site. Specialised tug boats equipped with powerful engines, helicopter landing pads, winches, pumps, small hospitals and fire fighting equipment are frequently used. Customised barges, cranes, submersibles and smaller boats are also used. Environmental experts monitor the operations to ensure that environmental, and hence financial risk are minimised.
The Kiperousa was en-route to the east laden with 23 000 tons of hardwood logs when its engine room flooded. Powerless, the ship drifted out of control and ran aground near East London, South Africa. If the ship were to disintegrate thousands of logs, each up to 25 meters long would be released into the environment. These would pose a huge threat to ships, boats and people swimming on beaches.
The Nikolay Chiker dwarfs the Amandla. The helicopter landing pad is at the front of the tug boat and the huge yellow winches with 15km of heavy cable are visible. Photo © Dr Jim Cambray.
The South African Salvors Smit Dudulu and the Greek based international salvage firm, Tsavliris, were engaged to try and refloat the vessel. The monstrous Tsavliris super tug, Nikolay Chiker, and the famous South African tug Amandla (formerly the John Ross) were rushed to the scene together with a team of 40 salvage experts.
The Nikolay Chiker was built in Finland in 1989. The mega tug is equipped with engines capable of generating 40 560kw (40 000 hp). This is approximately 1000 times more powerful than a family car. The tug has a maximum speed of 20 knots (37km/h). It also sports a large all weather helicopter landing pad, huge winches with 15 km of cable, pumps capable of emptying the equivalent of 2 Olympic swimming pools of water per hour and a small hospital. This machine is the most powerful tug in the world.
The Smit Amandla, formerly known as the John Ross, is a well known South African salvage tug. Currently it is under contract to the South African government in terms of the National Marine Pollution Prevention and Response contract. At one point, this venerable tug boat was one of the fastest and most powerful in the world protecting shipping routes past the Cape of Storms - one of the most dangerous in the world.
The two tug boats tried using all available power to drag the Kiperousa off the reef during a spring tide. This however went sadly wrong as shortly into the operation the Smit Amandla was badly damaged and left the scene. The bunker fuel on the Kiperousa was transferred to the Durban based Toto supply tug and the Nikolay Chiker remained on the scene anchoring the stranded ship and acting as a base for sea based operations.
A land centre of operations was established and Godfrey Needham acted as Salvage Master for Tsavliris. The load bearing structures of the ship were determined by a maritime architect, specialist divers and other qualified professionals. It was calculated that if the logs on the surface of the ship were removed, sufficient buoyancy would be freed to float the ship at the next spring tide and pull it from the reef. But how do you remove 1600 hardwood logs from the deck of a ship rolling in the waves 300m from the shore?
The hugely powerful Mil Mi26t helicopter lifts a 20t load of logs from the deck of the Kiperousa. Photo © Dr Jim Cambray.
Tsavliris hired a Russian made Mil Mi 26t Halo helicopeter (see article The Mil Mi 26 Halo - a scientific marvel 25 years on. Loaded with fuel and sufficient parts to fill two shipping containers, as well as its team of 6, the helicopter left Uganda and flew for 48 hours to reach the Kiperousa wreck. Working from dawn till dusk, the highly competent Russian helicopter team flew loads of up to 6 logs at a time from the deck of the ship to the landing site 10km away. At a cost of US$12 000 per working hour, a machine like this has a skilled and efficient crew keeping the operations moving swiftly, with not even one second (per second cost: US$3.30) going to waste.
Sadly, the Mil Mi 26t Halo (Titan) suffered a failure of a bearing on its rear rotor, forcing it to be grounded for a few valuable days. When the spring tide came, insufficient logs had been removed and the ship failed to move from the reef despite the most powerful efforts of the Nikolay Chiker.
Once repaired the helicopter resumed operations ferrying logs to land as fast
as possible. On some of the return flights, gigantic pumps were flown to the
Kiperousa. These pumps were placed on the deck and used to pump as much water
from the flooded hold of the ship as possible. The plan was to drag the ship off
the reef and then tow it at about 7 knots to nearby East London, where it could
With the removal of logs from specific sections of the ship, stresses were placed on the hull. To minimise the damage to the ship, the maritime architect flew to the ship on a daily basis, measuring the changes in the shape of the hull, and advising on where logs should be removed next to minimise structural strain.
After two months work on the operation, the Kiperousa shifted 90 degrees and was declared a wreck. At this point a new salvage contract was negotiated to ensure that damage to the environment was minimised and it was decided that the Kiperousa would become an addition to the reef.
The Mil Mi26t returned to North Africa where it began delivering aid to people in Sudan and the Nikolay Chiker returned to wait for the next opportunity to save people, money and the environment.
For more information on the exciting world of marine salvage visit:
The International Salvage Union
This site represents salvors around the world and is full of great information
Well we have all heard of Trainspotters, why can't we have Tugspotters as well?
From Greece, this huge salvage company appears to have some of the best equipment in the world.
John Ross and Wolraad Woltemade
For those of us who get a little misty eyed when we hear of these two venerable iconic South African tugs - lots of pictures and first hand information from crews.
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