Rolls-Royce has retrofitted new Zero Speed Stabilisers onboard Poseidon Expedition’s Sea Spirit to improve operational performance
Housed in a customised fin box, new retractable Rolls-Royce fin stabilisers were fitted to Sea Spirit during a dry dock in Lisbon earlier this year, to enable the ship to safely navigate the icy Greenland and Barents seas.
The stabilisers have an optimised lower fin angle to reduce drag while Sea Spirit is moving and minimise rolling while the vessel is anchored, moored or drifting. This reduces fuel consumption, enabling Poseidon Expeditions to lower its environmental impact. The stabiliser fins have a trailing edge designed to eliminate vibrations and noise, to enhance the onboard experience for guests and crew.
“The new system uses a computer-based programmable logic controller that develops different algorithms depending on conditions,” said Poseidon Expeditions senior director of cruise operations Nikolay Zakharov. “The result will be a ride for our passengers as comfortable as aboard any new expedition ship currently coming into the market. At the same time, they look to the future with safeguards to protect the polar ecosystems. The stabilisers are fully compatible with environmentally acceptable lubricants and feature quad main seals for additional redundancy.”
The latest version of Rolls-Royce’s stabilisation systems enables ice class ships to use the Stabilisation-at-Rest (SAR) system. Incorporated in both the Aquarius and Neptune ranges of Rolls-Royce retractable stabilisers, the SAR system employs active fin control technology and advanced hydrodynamic design to deliver roll reduction at rest while maintaining stabilisation performance whilst underway.
Martin Cunningham, managing director, Rolls-Royce Motion Control Dunfermline, said: “The one-piece fin construction offers simple maintenance, reducing through-life cost. The fin shape is designed to improve zero speed performance, as more chord is behind the fin centreline.
“This is achieved because the ice class SAR system is based on the well-established Rolls-Royce Aquarius and Neptune retractable stabilisers. Both initial and operational costs are minimised due to the units being easily installed, the fin box custom-designed to exactly match the ship’s hull profile, small hull opening and a simple reliable design.”
Recognising that the Rolls-Royce ice class SAR stabilisers are likely to be employed on vessels sailing in environmentally sensitive areas, a special quad seal arrangement ensures minimal risk of leakage, and the machinery is fully compatible with a wide range of environmentally acceptable lubricants (EAL).
“The sealing arrangement and compatibility with EALs mean the ice class SAR systems meet the requirements for VGP Permit vessels, while the low drag results in less fuel being burned, which also benefits the environment,” adds Mr Cunningham.
Sea Spirit, which has also been re-certified for new IMO Polar Code requirements, will operate Arctic itineraries in the summer and voyages in Antarctica for the rest of the year.
Principal particulars: Sea Spirit
Length overall (m): 90.6
Beam (m): 15.3
Speed (kn): 15
Engines: 2 x MAN 8L28/32A-FHO
Crew: 72Built: 1991
Yard: Nuovi Cantieri Apuania, Italy
Class: Bureau Veritas