DISCOVER Magazine #7

Unique cooperation leads to launch of new Rotor®tug ART 80-32 Hybrid

Published in category: Harbour & Terminal

In a move that took the tug industry completely by surprise Damen, Robert Allan Ltd., Rotortug B.V. and KOTUG International B.V. have teamed up in a recent project.

Damen’s new Harbour & Terminal Journal asks what brought a renowned tug designer and a world-class shipbuilder – which has its own extensive portfolio of tugs – together, even though they are more often known as fierce competitors. Undoubtedly, the key to this unusual move is the international maritime service company KOTUG – a customer of all of the companies.

Ard-Jan Kooren – better known as AJ – President of KOTUG, readily admits that it is a bold step adding, that KOTUG, Damen and Robert Allan Ltd. are all known to push the boundaries and this is no exception. It makes sense to bring a top designer and top builder together, he says.

Headquartered in Rotterdam, KOTUG is a four-generation family firm, established in 1911. Since 2005, the company has expanded rapidly purchasing more than 39 newbuilds, as well as some secondhand vessels from the market. The Dutch company now has some 50 tugs in its fleet, 30 of which are Rotor®tugs.

Originally designed by AJ’s father Ton, the Rotor®tug is dear to KOTUG’s heart, although KOTUG and Rotortug B.V. are now separate companies. KOTUG operates tugs in the Netherlands, Germany, the UK, Cameroon, Australia and has three on charter in Russia.

It just occurred to me one day, that we are building our vessels worldwide and why not have a relationship with Damen

Ard Jan Kooren

AJ explains: “It just occurred to me one day, that we are building our vessels worldwide and why not have a relationship with Damen – known as a quality, established company – right here in the Netherlands. Damen always has a good name as a quality company and being able to deliver in a very short lead time.”

During discussions that followed regarding KOTUG’s planned new building programme he outlined the new hybrid Rotor®tug design to Damen. “I asked why not consider building Rotor®tugs, alongside your own portfolio?” The three parties; Damen, Robert Allan Ltd. and Rotortug B.V. have signed an agreement, which allows Damen to build the Rotor®tug ART 80-32 Hybrid for third party clients.

“Damen is showing that it is client focused and an open minded shipyard in that it will build other designs, not just its own, and it will build what the client wants.”


We used to design and construct Rotor®tugs but now with Robert Allan Ltd. being the exclusive designer of the Rotor®tug, Rotortug B.V. is the patent holder and we provide a lot of input in the design process.

Evan Willemsen

Coen_Boudesteijn_Product_Director_Tugs_in_DamenCoen Boudesteijn, Damen Product Director of Tugs, comments: “For Damen it is a special experience to build Robert Allan Ltd. designed tugs at the high level of the Damen Standard for our customer KOTUG. Development of a complete new Damen design like ASD Tug 3212 takes us about three years. Quality is in the details! These Rotor®tugs are delivered with a lead-time of only 18 months.

This complete new design was the result of a dedicated team effort, encompassing our experience from the development of our proven ASD and Stan Tug Series. A number of truly innovative developments in the new Rotor®tugs ART 80-32 Hybrid are the result of a close cooperation of the Damen Tugs team, Damen Research, Damen Engineering and the Robert Allan Ltd. design team.”

Jim_HyslopAs well as being the first time Damen has built a Rotor®tug, this also represents that Robert Allan Ltd. is designing the Rotor®tug on an exclusive basis. Robert Allan Ltd. has designed the two Damen-built Rotor®tugs ART 80-32 Hybrid, as well as four standard Rotor®tugs being built in Cheoy Lee Shipyards in Hong Kong. Jim Hyslop, Manager, Project Development Principal at Robert Allan Ltd., explains more.

Established in 1930, the third generation Robert Allan still works at the naval architects’ firm, although the company was sold to a group of employees in 2008. Jim comments: “Independence is very important to us, we are not tied to any equipment manufacturers, yards etc. It is a real honour that Mr Allan trusts us to carry on and uphold the name, tradition and quality.”

Robert Allan Ltd. is probably most well known for its tugs, escort tugs, fireboats and ferries. Based in Vancouver, the company has designed boats for KOTUG for about 10 years and was officially named the exclusive designer of Rotor®tug at ITS in 2012.

Jim admits that the new KOTUG contract has taken a slight shift in mindset. “In many cases we compete with Damen tug designs and we work with a lot of yards that compete directly with Damen so again, we indirectly compete.”

Evan Willemsen, Managing Director at Rotortug B.V. adds that for Rotortug B.V. too, this contract has led to a new way of thinking. “We used to design and construct Rotor®tugs but now with Robert Allan Ltd. being the exclusive designer of the Rotor®tug, Rotortug B.V. is the patent holder and we provide a lot of input in the design process.”

We are proud to put the Damen logo on our site. We are all very proud to be partners.

Ard-Jan Kooren

He agrees with Jim that the new cooperation has taken some getting used to. “A few years ago Damen was our direct competition, as were all other naval architects and shipbuilders. So it has been a 180-degree turn.

However, at the end of the day we have actually teamed up with the major players in the world and together with the customer – in this case KOTUG – we can design according to our customer needs.”

Jim adds: “Ultimately this has come about because of KOTUG; they are our client and a good one. We trust them. Ton Kooren and Robert Allan mutually respect each other. KOTUG supports us and assists us to come up with the right solutions. It is an on-going collaboration process.

Damen is a quality yard and yes, we do have different philosophies in that Robert Allan Ltd. is more about custom-design, one-offs, while Damen is a specialist in standardisation. But I think we will all benefit from this arrangement as will the Rotor®tug concept.”

AJ emphasises: “If you consider the hybrid version, this saves 25% in fuel consumption and 45% in emissions. With this addition to the Rotor®tug range we are taking responsibility for any future rules and regulations to come. Like my grandfather and father, we are always pioneering.”

Coen adds: “With the new Rotor®tugs ART 80-32 Hybrid, Damen is pioneering in the field of customised tugs and unique in the shipbuilding world as it is the only shipyard building different types of hybrid tugs and building them for stock. These new generations of hybrid tugs are both economic and environmentally friendly. Damen has a distinct vision.”

“KOTUG, Damen, Robert Allan Ltd. and Rotortug B.V. are always looking at what’s going on in the market and we all have fantastic quality brands. We can learn from each other, we are leading companies doing a project and I look forward to future cooperation,” AJ stresses.

“We are proud to put the Damen logo on our site. We are all very proud to be partners.”

Evan Willemsen

The new Rotor®tug ART 80-32 class

The new Advanced Rotor®tugs (ART) will incorporate the patented triple Azimuthing Rotor®tug concept, featuring enhanced omni-directional manoeuvrability and the benefits of a fully redundant and precise propulsion machinery configuration. The Rotor®tug concept offers increased security for ship-handling and escort towing, as well as enhanced crew safety.

At 32 m long, the vessels have an installed power of 3 x 1765 kW, delivering a bollard pull of 80 tonnes over the stern and bow. The hull form has been developed from Robert Allan Ltd.’s high performance escort tugs. The Rotor®tugs ART 80-32 will also feature the XeroPoint Hybrid Propulsion System designed and supplied by Aspin, Kemp & Associates Ltd. and this is similar to the first E-Kotug, RT Adriaan, which is a retrofitted vessel operating in the port of Rotterdam.

Evan Willemsen, Managing Director at Rotortug B.V. says: “I can now concentrate on telling people the major advantages the Rotor®tug holds over any other propulsion configuration.”

In his opinion the main advantages are that the Rotor®tug is the only tug designed to work bow first – it is always able to sail bow first, he stresses. There is a lot of redundancy, with a high BP capability possible even if there is a failure. Operators never have to reposition their tug because they work well indirect or direct at all speeds, he adds.

And even in severe weather, the Rotor®tug can easily be controlled and manoeuvred. “Her high and immediate steering forces with little heeling angle at a vector response time of virtually “0” seconds makes it the best escort tug around. You never lose control. Rotor®tugs really created a different way of ship handling. There is push/pull method, which is very slow, but we don’t have to push on the side of the ship but against the tow wire instead, again with a zero response time to follow pilots’ orders.”

Ultimately, the Rotor®tug works very well in confined areas and this makes it possible to reduce the number of tugs per port call, he stresses.

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