Two Alconza electric motors for the RRS Sir David Attenborough, launched at Cammell Laird

Alconza strengthens its position as a manufacturer of low-noise electric propulsion motors for marine research vessels


Alconza has again positioned itself as a point of reference in the manufacture of electric propulsion motors for research vessels. This time it is two latest-generation 5,500 KW at 140 RPM motors incorporated into the RSS Sir David Attenborough, which was launched on 14 July in the British Cammel Laird shipyard. It will be sailing primarily in the waters of the Antarctic..

Marine research is the main task of the vessel, so it is essential for it to have silent, low-vibration motors in order to minimize the impact on the marine fauna and environment. In this respect it is worth noting that the two Alconza propulsion motors have a tandem configuration, they are directly connected to the propellers and they comply with the Det Norske Veritas (DNV) ‘Silent R’ standard.

The two electric propulsion motors are low speed so they do not need reduction gear and can operate from zero to 186 RPM. For its cooling system, Alconza has taken into account all the requirements on noise and vibroacoustics. These electric motors drive two Rolls-Royce propellers making up a propulsion package that has taken the ‘Polar Class 4’ technical requirements into account.

The low noise characteristics of the electric motors were decisive in the vessel’s compliance with the Lloyd’s Register (LR) Rules (CAC1), the most demanding in terms of structural noise and vibration. This compliance provides the crew with a high level of on-board comfort.

With its technological contribution to the RRS Sir David Attenborough, Alconza has demonstrated that it has the best technological and productive capacities to equip vessels of this type with solutions based on asynchronous motors with rigid mounting. This solution has many advantages over direct current motors on elastic support, which are normal in research vessels and make the propulsion package more complicated and more expensive.

As a first step to the delivery of the motors to the Cammell Laird shipyard, Alconza demonstrated the suitability of the technology used through Factory Acceptance Testing (FAT), in order to verify that the propulsion motors operate in accordance with the customer’s specifications.

RSS Sir David Attenborough is a research vessel that is owned by the Natural Environment Research Council of Great Britain. She will be operated by British Antarctic Survey, a body devoted to research in the Antarctic. It is 128 metres long and is considered one of the most advanced scientific ships in the world. She can sail for 60 days without refuelling and can break ice up to 1.5 metres thick.

The ship is capable of undertaking voyages of up to 19,000 nautical miles and being entirely self-sufficient in fuel and provisions, at the same time as optimizing the comfort and safety of the crew. Most of the passengers will be environmental scientists who will be carrying out their research on board the vessel. It therefore needs to have the best conditions of habitability and comfort, and Alconza’s technological input has made an outstanding contribution to this.

The name of the vessel is a tribute to the naturalist and scientific broadcaster David Attenborough, whose nature documentaries enjoy worldwide prestige because of their scientific rigour and their extraordinary audiovisual narrative, which is closely related to cinematography.