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4 Oceanographic Research Vessel Design The most important factors in oceanographic research vessel design. Does specialized research needs dominate the design criteria and, if so, what are the impacts on costs and overall availability? Ship design is an exercise in conflict resolution. It is the creation of a system of systems to perform a specific mission while balancing con- flicting requirements to achieve a ship capable of performing its mission in the best way possible within economic constraints. Oceanographic ship design is one of the very complex subsets of ship design, due to the large variety of oceanographic missions: physical, biological, and chemi- cal oceanography; marine geology and geophysics; ocean engineering; and atmospheric science. Each discipline has its own unique set of mis- sion requirements, yet a given ship is often called upon to perform work for a number of different disciplines, often on the same research cruise. In addition, the capital needed to build effective oceanographic ships is finite and scarce. Ships will remain the primary method of conducting oceanographic research, both through direct observation and through deployment and recovery of sensors, moorings, and vehicles. Driven in part by national oceanographic research objectives, research will be conducted in increas- ingly remote and environmentally challenging areas. Future ships must be able to perform their science missions in all areas of the oceans, includ- ing the margins of the polar seas. Specialized vessels (icebreakers) will also be needed to work in ice-covered regions. 47
48 SCIENCE AT SEA SCIENCE-DRIVEN SHIP DESIGN REQUIREMENTS The future science trends and technology advances that will drive oceanographic ship design have been described in Chapters 2 and 3. These have been synthesized into a matrix (Table 4-1). Several of these needs are unique to certain disciplines and are potential design require- ments that should be assessed carefully in general purpose oceanographic ship design. Other needs are more universal; for example, the ability to collect seawater samples throughout the water column is important for most of the oceanographic disciplines. Specific design considerations driven by the listed needs are discussed in the following sections. Handling Equipment Handling equipment overboard and onboard will continue to be of paramount importance, to allow for the safety of personnel, equipment, and the ship itself (Figure 4-1). Trends indicate that handling equipment must be able to operate effectively and safely up to sea state 6. General pur- pose oceanographic research ships require a permanently installed suite of winches (direct pull and traction) to perform conductivity-temperature- depth (CTD) type activities, deep tow, coring, and trawling missions. To expand the environmental operating window, active heave compensation has been incorporated on a number of recent ship designs. The Office of Naval Research (ONR) and the National Science Foundation (NSF) jointly funded a 2004 workshop to consider future handling systems. Recom- mendations from that workshop were used in motion compensation sys- tems installed on the Regional/Coastal class Sharp (Figure 4-1B,C), the Ocean class Kilo Moana, and the system designed for the Alaska Region Research Vessel (ARRV). It is likely that active heave compensation will be considered for all future University-National Oceanographic Laboratory System (UNOLS) vessels. Gliders, autonomous underwater and unmanned aerial vehicles (AUVs and UAVs), and remotely operated vehicles (ROVs) often require specific deployment and recovery procedures and equipment (e.g., Figure 4-1A). Although systems vary, deployment is usually much easier than recovery. While UAVs now use catchlines for recovery, advancements in remote aircraft are likely to change significantly in the future. Current oceanographic vessels, especially the larger classes, have high freeboard that makes recovery more difficult for offboard equipment. Requirements for damage stability and personnel safety in desired higher sea state â http://www.unols.org/publications/reports/lhsworkshop/index.html â Damage stability refers to the ability of a ship to have sufficient stability to survive a flooding casualty.
Table 4-1â Science-Driven Ship Needs Science Driver Physical Biological Chemical MG&G Atmospheric Atmospheric measurement capability X X X X AUV/glider/UAV stowage and handling X X X X X Capability to service observatories X X X X Clean laboratory space X X X X Controlled temperature laboratory space X X Dynamic positioning X X X X High data rate communication X X X X X Hull mounted and deployable sensorsa X X X X X Low radiated noise X X X Low sonar self noise X X X Manned submersible use X X X Mooring/buoy deployment and recovery X X X X X Multi-channel seismics X X Ocean drilling and coring X Precise navigation X X X X X ROV stowage and handling X X X X Towing nets and/or vehicles X X X X X Underway scientific seawater supply X X X X X Watercatching/water column sampling X X X Xb X aIn this instance, deployable sensors include centerboards, stalks, and towed sensors that can be lowered beneath the level of bubble sweep- down interference. bFor hydrothermal plume studies. 49
50 SCIENCE AT SEA (A) (C) (B) Figure 4-1â (A) An AUV being deployed using a custom OTS handling system (used with permission from ODIM Brooke Ocean). (B) The hands-free CTD han- dling system mounted on the R/V Sharp, which allows the CTD to be deployed and recovered without personnel holding the rosette. (C) A CTD deployed using the R/V Sharpâs OTS CTD handling system. The motion compensating function keeps the CTD at designated depth without regard to the motion of the ship, once deployed. (B and C used with permission from William Byam, University of Delaware). operations are likely to exacerbate this issue. Existing options, including using a small boat or a grapple to hook gliders, AUVs, or ROVs, will be less viable in rough weather conditions. Development of over-the-side (OTS) lifting equipment, either portable or permanent, will be neces- sary to protect equipment and personnel. However, designing handling equipment that is optimized for current OTS equipment could negatively impact vessel utility over the 30-year lifespan of a ship. Instead, this type of equipment should be designed with future needs in mind.
OCEANOGRAPHIC RESEARCH VESSEL DESIGN 51 Acoustic Quieting Acoustic quieting requirements are essential for many missions (e.g., shipborne acoustic sensors, acoustic releases on equipment, offboard platforms with acoustic communications). Double raft mounting and/or resilient mounting will be increasingly desirable. Achieving compliance with ship-radiated noise recommendations set forth in the International Council for the Exploration of the Sea (ICES) report Underwater Noise of Research Vessels (commonly referred to as ICES 209; Mitson, 1995) is likely to be costly, and mission needs must clearly warrant imposition of this requirement if costs are to be minimized. Some recent and planned vessels, including the ARRV and RRS Discovery, are attempting partial compliance with ICES 209 specifications for a manageable and economic solution to ship-radiated noise. Attention should also be paid to ambient noise and its impacts on habitability for the ship crew and science party, especially when round- the-clock operations are undertaken. The positioning of berthing and accommodations should be designed to avoid unnecessary and disturb- ing ambient noise. Dynamic Positioning Dynamic positioning is critical to handle deployment, recovery, and operation of offboard vehicles safely. Design conditions should strive to maintain position beam-on in at least sea state 6-7, 30-knot winds gust- ing to 40 knots, and a 0.5-knot surface current all from the same direction (Williams and Hawkins, 2009). The current Ocean class Science Mission Requirements (SMR) require that the ship be designed to maintain posi- tion in sea state 5, a 35-knot wind, and a 2-knot current (UNOLS Fleet Improvement Committee, 2003b). Laboratories and Working Decks There will be a continued need for plentiful laboratory and working deck space and capabilities. Laboratory space should be divided between ultraclean, clean, normal, and temperature-controlled areas, with sufficient flexibility to be used for multiple needs (Williams and Hawkins, 2009). There should be ease of and logical access into and between lab spaces for personnel and sample movements. Vessel design should include a substantial scientific stores area, including areas for frozen and refriger- ated sample storage (Daidola, 2004). Working deck design must be open and clear, with tie-downs for equipment and containers. There should be flexible deck space to sup- port the use of laboratory and equipment vans, and easy and safe access
52 SCIENCE AT SEA to covered working areas using integrated overhead lifting gear. Decks must be able to handle increasingly heavy gear, including moorings, fleets of autonomous vehicles, and ROV equipment and winches. Freeboard should be as low as possible to allow for optimal handling of over-the- side equipment while keeping decks dry. Berthing and Accommodations Accommodation trends aboard research vessels include more single berthing for crew, specialized technicians, and scientists; berthing with natural light to promote natural sleep patterns; and galley and relaxation spaces that promote a healthy lifestyle at sea (Williams and Hawkins, 2009). The quality and design of crew living spaces are paramount for employee retention and morale. Specifications for noise levels and envi- ronmental conditions in both interior laboratory spaces and living quar- ters should strive to minimize ambient noise levels. Other Design Attributes A number of other scientific and operational trends will drive oceano- graphic ship design in the future (Daidola, 2004; Williams and Hawkins, 2009). These include the following: â¢ Larger, multidisciplinary science parties to make the best use of the ship resources and collect interdisciplinary and/or complementary data â¢ Longer cruise durations ranging over larger areas of the ocean â¢ Increasing desire to work in areas of rougher weather, demanding vessels capable of operating in higher sea states â¢ Specifications that comply with the Americans with Disabilities Act (ADA) â¢ 24/7 operations â¢ Higher-resolution and specialized hull-mounted swath bathymetry and sonar systems â¢ Larger and heavier pieces of portable science equipment â¢ Deployment, recovery, and maintenance of specialized offboard equipment â¢ More specialists (in addition to marine technicians) to service com- plex equipment â¢ Operational safety The impact of these trends on dimensions and displacement is discussed later in this chapter.
OCEANOGRAPHIC RESEARCH VESSEL DESIGN 53 DESIGN CHARACTERISTICS AND DESIGN DRIVERS Table 4-2 displays ship design characteristics that are dictated by science needs as well as other characteristics inherent to setting future mission requirements that may have a significant cost impact. These design drivers are assessed by their priority (1-9, with 9 being the high- est), established by the scientific community, and by their degree of ship impact (low-high), assessed by naval architects (UNOLS Fleet Improve- ment Committee, 2003b; Dan Rolland, personal communication, 2009). A âhighâ impact means that the shipâs capital cost will increase if that requirement is met. For example, dynamic positioning is important for many types of science missions and has a large impact on ship design. The thrust delivery and control required add significantly to the ship construc- tion cost, but given the high associated priority, dynamic positioning is likely to be an investment with widespread use. Conversely, aiming for higher ship speeds also has strong impacts on ship construction cost, but with a much lower priority. This indicates that when ship mission require- ments are set, care should be taken to fully justify any speed that is on the steep side of the power curve. A corollary impact of higher speed is greater fuel consumption, leading to increased operating cost, and greater fuel tank volume, which can increase ship cost. Efficiency Efficiency is a vital consideration in the design of future oceano- graphic ships. Seeking a design with high propulsion efficiencies will lead not only to a lower operating cost but to a âgreenerâ ship. Efforts to be more environmentally friendly often result in the addition of equipment to reduce emissions, which requires space in and adds weight to the ship in addition to its own costs, increasing ship construction costs. However, the potential for stronger regulations on emissions in particular local or regional areas (exist in the North Sea Sulfur Oxide Emission Control Area; International Maritime Organization, 1997) will affect ship design require- ments and will not be achievable with current UNOLS vessels. Future oceanographic ship design may have to anticipate this by creating space and weight to comply with as-yet-undefined requirements or by accept- ing construction and operation cost increases associated with emission reduction measures. Other control measures, such as a carbon tax, could also drastically change the economics of traditional propulsion plants. Recent increases in fuel costs dictate that high priority should be given to improving propulsion plant efficiency and reducing ship hull resistance. Many recent academic research vessels, such as Atlantis and Kilo Moana, have used some form of electric propulsion, and currently the Navy is contemplating shifting its combatant fleet toward integrated
54 SCIENCE AT SEA Table 4-2â Research Vessel Design Drivers Ship Design Driver Priority Ship Impact ABS class/USCG certified 9 High ADA accessibility 9 High Working deck area and arrangement 9 High Laboratory area and arrangement 9 High Draft (less than 20 feet) 9 Moderate Dynamic positioning capability 9 High Fuel efficiency 9 Moderate Maneuverability at slow speeds 9 Moderate Sonar self noise 9 High Bubble sweepdown 9 High Seakeeping 8 High Number of science accommodations 8 High Crane handling on deck and on/off ship 8 High Overboard handling operations 8 High Overboard discharges/stack emission 8 Low Other scientific echosounders 8 Moderate AUV/ROV handling and servicing 7 Moderate Workboat handling 7 Moderate Science storage 7 Low On deck incubations, locations/water 7 Low Long coring capability 6 High Mast location, met sensors 6 Moderate Rangea 6 High Speed 6 High Variable science payload 6 Moderate Radiated noiseb 6 High One degree deep water multibeam 6 High Endurance 5 Low Ice strengthening 4 High Marine mammal and bird observations 3 Low aThecommittee thinks that âRangeâ deserves a higher priority than the value shown in this table, due to growing needs for ships capable of reaching distant research sites. bThe committee thinks that âRadiated noiseâ deserves a higher priority than shown on this table unless âSonar self noiseâ (which has a high priority) is controlled. SOURCE: Adapted from UNOLS Fleet Improvement Committee, 2003b; Dan Rolland, per- sonal communication, 2009.
OCEANOGRAPHIC RESEARCH VESSEL DESIGN 55 electric drives. This trend has resulted in larger research and develop- ment expenditures for naval combatant electric propulsion, and future oceanographic ships are likely to benefit from advancements in power conditioning, reductions in plant size, and reductions in fuel consumption for a given power level. There are other efficiencies to be considered. The performance of a research vessel is based upon the quantity and quality of the data it produces. A variety of issues can impact ship productivity, including the amount of time taken to deploy equipment to full depth and recover it, the time taken to change over from one piece of equipment to another, and time lost due to breakdowns in the winching and OTS handling equipment. This is increasingly important on multidisciplinary cruises, which often require capability for a variety of equipment to be used at any one site. Although little can be done to improve deployment and recovery speeds through the water column due to the limiting hydrodynamics of the equipment and potential for damage due to overspeeding, the U.K. academic research vessel RRS James Cook was designed to substan- tially reduce the time for equipment changeover and breakdown losses. Winches are arranged to allow all wires to be permanently rigged up and quickly connected, while a system of sheaves allows any wire to be led over any of the main OTS handling equipment (Robin Williams, personal communication, 2009). These types of ship arrangements permit a high degree of integration and support diverse science objectives simultane- ously, thus allowing more science to be carried out per day and increasing the shipâs efficiency. General Purpose and Specialized Design Requirements Large general purpose vessels yield an economical long-term fleet that can satisfy uncertainty in future mission requirements. Although general purpose ships will serve a broad spectrum of future research activities, some scientific mission requirements will call for special purpose ships. These include fisheries surveying, which requires very quiet platforms; operations in the marginal ice zone, which result in specialized hull struc- ture; deep submersible operations, which need strengthened A-frames and specialized hangar spaces; and three-dimensional (3D) seismic stud- ies, which require large reinforced deck spaces to accommodate streamer reels, large-capacity compressors for air guns, rigging and booms for handling air gun arrays, and the ability to tow multiple air gun arrays and/or streamers (Daidola, 2004). Of these, seismic needs are currently â For example, the Zumwalt-class destroyer DDG1000.
56 SCIENCE AT SEA addressed with the Marcus Langseth; Atlantis serves as the tender for the Alvin manned submersible; and the NSF-funded ARRV will allow for work in marginal ice. These specialized ships are relatively young: Marcus Langseth was converted for research service in 2008, Atlantis was built in 1997, and the ARRV is anticipated to come online in 2014. Based on the evolving science and technology needs identified in Chapters 2 and 3 and the existence of capable specialized vessels, readily adaptable general purpose ship designs are most needed in the future fleet. The UNOLS fleet does not currently have any specialized fisheries vessels, although the National Oceanic and Atmospheric Administration (NOAA) operates four ultraquiet fisheries vessels and is slated to build three more by 2018 (Office of Marine and Aviation Operations, 2008; Tajr Hull, personal com- munication, 2009). There are a number of ship design trends involving displacement and dimensions that are useful to consider, including (Williams and Hawkins, 2009) â¢ Increased beam, which increases damage survivability; â¢ Increased length, which improves the hull form for powering and control of bubble sweepdown over hull mounted transducers; â¢ Increased draft, which reduces bow emergence in a seaway and reduces bubble sweepdown; and â¢ Increased displacement, which supports increases in range, roll stabilization, science outfitting, and over-the-side lifting equipment weights. Beam has been increasing as a result of stronger standards for damage stability but is likely to stabilize. Draft has also increased over time, likely due to the need to minimize bubble sweepdown for hull-mounted sonar systems. Minimization of bubble sweepdown has proven to be extremely challenging and can be a significant design driver for ships carrying these devices (Robin Williams, personal communication, 2009). Increasing beam and draft for conventional hull forms implies increased displace- ment, which leads to higher costs for ship construction. However, larger ships capable of carrying more scientists and performing more scientific experiments do provide an economy of scale. While adding more berth- ing and lab space increases ship construction costs, the cost per scientist decreases. This is supported by UNOLS statistics from 2008, where the average daily cost per scientist was higher for the Ocean ($1,062) and Intermediate ($982) classes than for the Global class ($946; data from UNOLS office, 2009).
OCEANOGRAPHIC RESEARCH VESSEL DESIGN 57 International Maritime Organization (IMO) MARPOL Regulations The United States is a party to Annex 1 of the IMOâs International Convention for the Prevention of Pollution from Ships (MARPOL), which regulates oil pollution. A 2007 amendment to Annex 1 is likely to have a significant effect on the design, cost, and operation of future research vessels. Ships with fuel capacity of more than 600 m3 will be required to enclose the fuel tanks within a double hull. Several of the current Global class vessels (Revelle, Atlantis, Thompson, and Langseth) have fuel tanks with greater capacity. This regulation has the potential to severely restrict the range of larger ships of the academic fleet, which in turn will affect scientific activities. Although ships built using Navy funds could be exempt from these regu- lations, the amendment provides a significant driver toward more fuel- efficient operations, including lower transit speeds, more streamlined hull forms, and efficient power generation and distribution systems for future Global and Ocean class vessels. THE SHIP ACQUISTION PROCESS The Navyâs acquisition process related to the academic fleet has a significant impact on both ship cost and quality. The time from concept to delivery of any ship constructed with federal funds is extraordinarily long: the proposed new polar icebreaker is projected to take 8 to 10 years to enter service (National Research Council, 2007), and the new ARRV has taken more than 30 years of planning (http://www.sfos.uaf.edu/arrv/). Because of the lead times involved, it is vital that the most capable ship is constructed. Since decisions made at the earliest stage of design can have the greatest impact on the life-cycle cost of a ship (Bole and Forrest, 2005), science users need to participate in setting initial requirements and design specifications and to be included in the evolution of the design. This is especially important when the research requirements are translated into ship specifications, because poor decisions at this stage often yield a ship that will be unsatisfactory or uneconomical to operate. One strategy that almost guarantees an unsatisfactory solution is the use of poorly defined performance specifications. Shipbuilding is a business, and shipbuilders must compete for contracts that are usually awarded to the lowest bidder. If specifications are not tightly defined, the shipbuilder may use inexpensive and unsatisfactory approaches to construction. Some of the recent UNOLS vessels procured through the Navy acquisition process have been constructed with poor attention to â http://www.imo.org/Conventions/contents.asp?doc_id=678&topic_id=258#7.
58 SCIENCE AT SEA detail because of this approach. Examples include the use of iron piping instead of copper-nickel for potable water systems because pipe material was not defined (as on Thompson), or deck drains that are not located at the local low point (thereby not working effectively) because the designer failed to specify a location (on Atlantis). There have even been cases where the drain piping has been run against grade (both Revelle and Atlantis). There is simply no substitute for specificity in fixed-price contracts, such as those the Navy uses to procure academic ships. While cost constraints may preclude securing a ship with every desired specification, improvements could be made to the current system. Since hull structure is one of the cheapest aspects of a complete ship, one alternative to the current approach might be to consider building a larger ship than may appear to be affordable and bid certain scientific systems separately. This would allow for âmix-and-matchingâ the systems, creat- ing a ship that does some part of the overall mission very well. Other capabilities could be deferred for a future refit, with unfinished space left for future equipment purchases and installation. Another alterna- tive would be for the procuring agency to purchase certain high-tech equipment separately and provide it to the shipbuilder for installation, ensuring that the desired equipment is installed rather than a lower-cost component that would require replacement and increase life-cycle costs. One caveat with this approach is that equipment must be delivered to the shipyard on time, and any required interfaces with the ship must be correctly and precisely defined. If this is not done, the shipyard will likely consume all potential cost savings by claiming increased costs due to delay and disruption associated with failure to be timely and properly defined. A common hull design between vessels of each class, as done previously with Global class ships (i.e., Thompson, Atlantis, Revelle, and the NOAA ship Ronald H. Brown), could also provide cost savings. NSF created a design and construction plan for the AARV that was intended to address many of the problems that have impacted earlier oceanographic ship acquisition programs. The ARRV process involves the scientific user community in the design and construction of an oceano- graphic ship from the preconstruction phase through post delivery of the ship. It is summarized in Box 4-1. CONCLUSIONS The fleet of the future will be required to support increasingly com- plex, multidisciplinary, multi-investigator research. The design of future oceanographic ships is likely to become more challenging in order to achieve the needed integration and balance of facilities and equipment. Multidisciplinary, multi-investigator cruises will drive many aspects of
OCEANOGRAPHIC RESEARCH VESSEL DESIGN 59 Box 4-1 The ARRV Procurement Process The ARRV is being built under the direction of NSF to support research in coastal and open ocean settings, particularly in those regions that experience mod- erate seasonal ice. ARRV, as the first ice-strengthened ship to join the academic fleet, requires special capabilities and presented engineering challenges that do not apply to more general purpose vessels. In order to provide strict oversight for vessel fabrication, NSF implemented a four-phase building project that required successful completion of early phases before funding would be awarded for subse- quent phases. The phases included a project refresh (design review), yard selec- tion and acquisition, ship construction, and delivery and transitions to operations. A key element of the process was the creation of an ARRV Oversight Commit- tee to obtain community input and advice on ship design and construction during all of the phases. This included a review of a final refreshed design and de-scop- ing plan, draft shipyard contract, and shipyard scope of work; a periodic review of ARRV construction progress; review of delivery voyage and the shakedown science test cruises; and review of warranty period and final acceptance. The oversight committee provides advice on the establishment of design and budget priorities, ensuring that construction remains within the agreed scope and cost. The committee was established and supported by the University of Alaska, Fairbanks (UAF), and its membership and scope of activities are approved by NSF. The committee is responsive to NSF and UAF by providing reports that detail and track the status of recommendations. The committeeâs membership is fluid and may change depending on needed expertise for each phase of design, construction and trials. The ARRV procurement process entails a competitive two-step shipyard selec- tion process. Step 1 is the competitive qualification of shipyards through a technical proposal submission. Step 2 is a best-value price competition among acceptable shipyards in response to a request for cost proposals. Shipyards that do not pass Step 1 are expected to be eliminated to reduce risks of procurement delay, allow fewer potential protest risks or expenses, and maintain strong price competition among acceptable shipyards. The shipyard selection process begins with a request that interested shipyards demonstrate their qualifications for the ARRV project. The request includes the baseline project design package, a thorough description of the selection process (including evaluation methods), and detailed instructions to the potential offerors. design, including power plant and propulsion, laboratory and working deck layout, over-the-side handling, launch and recovery, and equip- ment changeover. Larger science parties and more complex technology will require more laboratory and berthing space. The growing trend toward use of multiple offboard vehicles will also impact the design with respect to freeboard and deck space. Vessel design will have to incorpo- rate technology that is currently available, such as dynamic positioning or
60 SCIENCE AT SEA state-of-the-art sonar, while remaining adaptable for future technological upgrades. The capability to operate in high latitudes and high sea states will also be required. Because technology changes rapidly and ship lifespans are long, future academic vessel designs need to be general purpose and highly adaptable to changing science needs. Specialized ships will also be needed for some disciplines, with designs that are well matched to disciplinary needs while also being available for limited general purpose work. Trends toward increasing beam, length, draft, and displacement and the economy of scale present in larger hulls suggest that investments in larger, more capable vessels in any size class are preferred. The current Navy ship acquisition process does not emphasize inclu- sion of the scientific community in decision making regarding academic ship design and specifications. Development of the NSF-sponsored ARRV has benefited from community-driven ship design, allowing the users to participate more fully and create optimal designs for the cost constraints.