Tri-party design WFSV

MO4 is unique to the market in several respects
MO4 is unique to the market in several respects
Mainprize's MO4
Mainprize's MO4
MO4 has a huge working deck area of over 120m2
MO4 has a huge working deck area of over 120m2
MO4's shallow draft design gives an even greater operational window in a tide restricted port
MO4's shallow draft design gives an even greater operational window in a tide restricted port
The vessel can carry up to 24 passengers, under the ‘offshore personnel’ designation
The vessel can carry up to 24 passengers, under the ‘offshore personnel’ designation
Radar and comms have been supplied by Furuno and Bee respectively
Radar and comms have been supplied by Furuno and Bee respectively

Mainprize Offshore is working hard to attract even more business from the still growing market for offshore wind, so it has built its cleverest windfarm service vessel yet, the MO4.

The vessel paid a visit to this year’s Seawork International exhibition en-route to its first commission, an eight-year term with Deutsche Windtechnik, working on Germany’s offshore windfarms.

Tri-party partnership
Constructed as a triparty design between Mainprize Offshore, Aluminium Marine Consultants (AMC) and Walker Marine Design, MO4 measures in at 23m in length and 9.6m in beam and has a draft of 1.4m and provision for 30t of deck cargo.

Interestingly, the MO4 is one of the operator's smallest vessels (although it is apparently the largest 23m vessel around), but it is arguably the cleverest.

Because MO4 has a huge working deck area of over 120m2, it’s one of a handful of WFSVs in existence which have this much deck space, the area is 30 to 40% greater than some much larger vessels.

The vessel also has 30,000 litre fuel oil capacity and 20,000 litre fresh water capacity onboard.

Another aspect that makes the vessel really unique is its shallow draft design which gives an even greater operational window in a tide restricted port.

Behind the design
It’s the second vessel design for Mainprize Offshore for the naval architect James Walker. The first was the 25m MO3 WFSV, one of two vessels built for the operator back in 2014.

The MO4 is designed specifically for its new client which specified the type of vessel it wanted.

“We have a joint venture arrangement with Mainprize,” said Mr Walker.

He explained that the design for the MO4 took the baseline design for the MO3 but it was modified to suit the client’s requirements.

The MO4 is in Bob Mainprize’s own words, a “Swiss Army Knife”.

“It’s a multi-role small supply ship with plenty of deck space and cargo tanks. The vessel can undertake multiple tasks, it’s not just putting backsides on seats which is what the majority of windfarm service vessels do,” Mr Walker said.

He added that the MO3’s first contract was on a diving project and that the MO4 has also been built to undertake a variety of different tasks and work in a variety of sectors.

With a history at South Boats before starting out on his own, James Walker has become synonymous with high spec WFSV design, including projects with CWind and Manor Marine, among others.

Build specs
The MO4 is fitted with Finning Cat supplied twin Caterpillar C32 diesel engines, ZF 3055 Gearboxes and a Clements stern gear package, giving the vessel a service speed of 26 knots, even when fully loaded.

MO4 also has a Palfinger 4501M crane, rated 1 tonne@7m SWL with radar and comms supplied by Furuno and Bee respectively.

Lifeboats and safety equipment have been supplied by Viking and Seasafe.

The vessel can carry up to 24 passengers, under the ‘offshore personnel’ designation.

It’s currently configured for 12 pax, but Bob Mainprize says that to achieve 24 pax would only require a small alteration that has been designed into the construction and layout of the saloon.

So, it’s a quick and simple change over to perform with all regulations covered in full.

An innovative build
MO4’s builder, AMC, is no stranger to the lucrative offshore windfarm industry.

This is the first time that Mainprize has entrusted AMC with one of its builds and when asked why the change in builder this time, Bob Mainprize said that put simply: “They were the right builders for the job.”

Another reason AMC was selected for the job is because Mainprize was working to a tight build schedule and AMC was one of the few that could have delivered.

Mainprize has had a bit of bad luck with its newbuilds in the past. In 2013, the construction of two of its vessels was ground to a halt as Buckie shipyard went in to administration following cash flow problems. So, having a builder it can rely on is fundamental for the operator.

AMC is synonymous with high-profile orders for many of the leading windfarm service vessel operators, including CWind and Turbine Transfers.

The latter saw AMC delivering one of its highest profile projects to date with the ‘Trearddur Bay’ windfarm service vessel.

From Keel Being laid to handover, the build of the MO4 took less than nine months which exceeded all expectations and enabled MO4 to go into its charter four months earlier than expected.

This is something that Rob Stewart, commercial director, AMC, is particularly proud of.

Mr Stewart pointed out that this is largely down to the firm’s “flexible build approach.”

“Due to the nature of the beast, build specifications can somewhat change during a project, which does cause challenges throughout the build, but AMC offers an open and flexible approach to construction so that the end result is exactly what the customer requires,” he said.

He said that the MO4 project was both “fascinating and progressive” and allowed AMC’s attention to detail and workmanship to come to the forefront during the build.

It’s also a landmark build for the firm.

“This build project was immensely important to AMC because MO4 is a ground-breaking design offering extensive fore and aft deck space and huge saloon capacity to enable a quick change to 24pax if required.”

“The collaboration between AMC, Walker Marine Design and Mainprize Offshore has resulted in an outstanding design that is more than fit for purpose.”

Going forward
Mainprize’s future vision for windfarm service vessels doesn’t just stop with the MO4 though. It’s next build, the MO5 looks set to dwarf even the sizeable MO4 and it will have a new and unique hull design to boot.

The MO5 is born from an idea that Mr Mainprize had six years ago, but it wasn’t the right time then to move ahead with the project.

However, he tells MJ that the time is now right and the plan is to unveil the new vessel at Seawork International 2018.

By Anne-Marie Causer

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