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Mission Possible: Reinventing the Keel

Maritime Activity Reports, Inc.

December 15, 2011

(The M/V Susitna can lower its buoyant vehicle deck to decrease the hull draft for landing craft operations.) photo by Charlie Starr, used by permission from Alaska Ship and Drydock.

(The M/V Susitna can lower its buoyant vehicle deck to decrease the hull draft for landing craft operations.) photo by Charlie Starr, used by permission from Alaska Ship and Drydock.

When vessel owners and operators opt to bite the bullet and invest millions of dollars into a new workboat, it is reasonable to assume that they will start shopping with the expectation of procuring the most boat that their Limited money can buy.

 

Capital investments of this magnitude are often justified solely upon the premise that a new custom-designed vessel will have more functionality and thus greater revenue generating capability. Why buy a workboat unless it can pay for itself? With fewer dollars being spent these days, boat builders and designers are more eager to rise to the challenge, push the envelope, and create the revenue generating multi-mission marine machines that owners have long been dreaming about. 

 

Swiss Army Vessel Design
 

Purely from an economic perspective, a multi-purpose tool makes the most sense – right?  Many owners will attest that the survival and success of their operation largely depends on their ability to employ each craft in a vast variety of jobs. The pros of a multi-purpose and multi-mission workboat sound great at the conceptual level, but pulling it all together into a package that floats is quite complex and often problematic. It may not be too much of a stretch to design a passenger vessel that can host burials at sea in the morning, whale watching tours in the afternoon, and a cocktail cruise at sunset, but when the tasks at hand require multiple pieces of machinery and a reconfiguration of the working deck, the complexity of the boat design is taken to another level.
 

Alaska Ship and Drydock’s latest launch, the M/V Susitna, is the epitome of versatility in vehicle ferry configurations. Not only does the vessel feature a highly stable, ice strengthened SWATH hull, but its adjustable vehicle deck gives the vessel the ability to vary the draft for landing craft capability.  While this kind of Swiss Army Knife design approach offers great versatility, it also comes with a premium price.

 

Right Tool for the Job
 

In certain applications, the mission is so critical and unique that a specific vessel configuration is absolutely required for completing the job. Over the years, basic marine missions have remained virtually unchanged. Harbors still require patrolling. The sea floor requires mapping.  Cargo requires moving. Rigs still require support. Accordingly, workboats have remained steadily employed and in demand, over time. Though the needs remain unaltered, the technology for enhancing mission-specific performance has evolved. Efficiency and effectiveness can make the consideration of a new mission-specific vessel very appealing.  Take for example the new Response Boat Medium and the forthcoming next-generation Response Boat Small, which have incorporated advanced technology for patrol boat missions that increases both the safety of the crew while also augmenting effectiveness in mobilizing threats.
 

Foss’ hybrid tug is also making waves with a greener propulsion system that has reduced emissions, yet still tough enough to push and pull conventional loads. When Ulstein Group unveiled the unconventional X-bow hull shape maximized for efficiency and seakeeping ability, it quickly became clear that perhaps one core vessel design could be used in multiple mission-specific applications.  X-bow configurations have since been developed for an array of mission-specific vessels working in short sea shipping, offshore supply, sub-sea exploration, and now there is even potential for a wind farm installation application.
 

Sometimes even the latest technology cannot replace the most tried and true mission-specific craft. After twenty-five years of good service, NOAA went back to the naval architects at Jensen Maritime Consultants for a contemporary redesign of their survey launches. After all the input was given and feedback exchanged, NOAA ended up with a replacement fleet of survey boats that closely resembles their older versions.

 

From Dreams to Design:

 

Unconventional radicals opting to reinvent the keel on the workboat of their dreams must define each mission’s specifications before the keel is laid. Shooting for the moon is not a successful approach as boats are only built via compromise. A key guideline when designing a multi-mission vessel is to adhere to the likely unfamiliar, yet practical, ‘Stiletto Principle’.  The principle was aptly coined when a customer was insistent that every aspect of the vessel, from construction materials to the deck plans was meticulously designed to be easily accessible and safe for a person wearing high-heel stiletto shoes.  While stilettos are rarely found on today’s seagoing workboats, the merit of the principle should not be ignored. The limiting factor for successful vessel design must be clearly established and reasonable. Once the factor is identified, all other wants, concerns, and specifications must be prioritized in order of importance. Furthermore, remember that builders and designers will always be bound by the laws of physics despite the magnitude of their creative talents.  
 

Reconfigurable deck space is a sensible solution for the multi-mission vessel; however, deliberate consideration should be given to each configuration that may have an impact on the weight and balance of the vessel. Stability and performance are the most sensitive traits impacted by multi-mission vessel design. Depending on the diversity of the missions, naval architects may struggle to find a solution that keeps the boat afloat and up to speed. Vessels always perform better when they are balanced and mitigation through the use of ballast water is not as easy and environmentally acceptable as it used to be. Buyers must also determine if it makes sense to include an adaptation that may inhibit performance by 20% every time the vessel moves, especially when the adaptation may only be utilized 5% of each year. For example, the WAM-V hull by Marine Advanced Research was specifically designed for easy reconfiguration. The craft features a spider-like chassis that can be equipped with interchangeable pods, which are self contained and customized for each job.
 

Support system requirements for various missions should also be measured in order to confirm that that the vessel can supply the needed power and hydraulic demands for each task.  Systems can always be expanded to comply with maximum demand, but also consider the cost of maintaining the larger system when full capacity is not required. C&C Technologies wanted their new propeller driven, multi-mission catamaran to perform efficiently at both 11 knots and 20 knots. The cost of installing two high horsepower engines could not be justified when the vessel was operating for hours on end at lower speeds. The compromise that calculated for both missions was a design that incorporates two different sized engines in each sponson. High speed missions can now succeed when all four engines are running and likewise the low speed missions are efficient with the operation of just two smaller engines.
 

The workboat industry benefits over the pleasure craft market in that our vessels are custom designed and fabricated, without the restrictions and confines of a pre-shaped mold. Every new workboat project gets the benefit of lofting from a clean slate, but typically it is without the budgets found in the fat wallets held by yacht buyers. Our industry is truly forced to do more with less. By choosing a vessel design that is too mission-specific, the craft may lose usefulness and value over time, through lack of versatility or adaptability. Conversely, installing too many features and adaptations leads to higher maintenance costs and increases the capacity and requirements of onboard support systems.

 

The Winds of Change
 

Workboat designs are changing and will continue to change. The newly emerging wind farm industry is bound to generate the need for many new mission-specific and multi-mission platforms. Forthcoming regulations will continue to impact the design of workboats and how they are operated. Tighter capital budgets will push workboat buyers to ask for more – and, if you don’t ask, you won’t get. The silver lining is that technology is on everyone’s side and will continue to push our working boats upstream, at least until Ron Popiel unveils the one workboat that can do it all.

 

Joe Hudspeth is Business Development Manager at All American Marine, Inc., a manufacturer of high speed passenger ferries, excursion vessels, and work boats, in Bellingham, WA. Hudspeth currently serves as a regional co-chairman for the Passenger Vessel Association and participates regularly on several committees concerned with marine related issues. Joe can be reached at [email protected].

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