French inertial navigation specialist iXblue commissioned and began operating its new hydrographic research vessel in June 2016. The FeliX is a composite catamaran designed, built and outfitted by iXblue companies. Although the design caters for hydrographic surveying and oceanographic and biological research, most missions to date have focused on R&D for marine renewable energy programmes.The FeliX is the only vessel on the French market offering R&D services to the MRE community. She was built by the ex-H2X yard at La Ciotat for operator iXSurvey. Today, iXSurvey — now known as Sea Operations — and the shipyard are divisions of the iXblue group, a development which has made the group more vertical while retaining the parent company’s traditional focus on inertial navigation tools. These changes help group teams built up over time to work together more effectively by making better use of their complementary skill sets.A well-equipped boatWith a length overall of 24.9m and a beam of 8m, the FeliX is equipped with a pair of 450-hp Scania diesels powering two bow thrusters and a pair of azimuth pods producing a top speed of 13 knots. The boat is also equipped with a DP1 dynamic positioning system. The FeliX offers ten days’ endurance, sufficient for relatively long missions or to transit directly to a distant work area. © IXBLUE The FeliX hydrographic vessel at sea (© iXblue) The FeliX’s 55-sq.m workdeck is equipped with an aft A-frame and tackle enabling it to launch a wide range of instruments, including magnetometers, a Geometrics G882 gradiometer, a Klein 3000.3900/Shadows sonar, and sediment and water samplers. A moonpool facilitates the deployment of an ultra-short baseline global acoustic positioning system, or USBL GAPS. The projector of the boat’s R2Sonic 2024 wideband multibeam echo sounder is housed in a hull dome along with an Echoes 3500 sub-bottom profiler. The FeliX can also deploy a remotely operated underwater vehicle (or ROV), a small bottom corer (to sample the sub-seabed along cable pathways between offshore windfarms and shore facilities), towed streamers for seismic surveys and special-purpose instruments to study windfarm sites (e.g. devices to suppress coastal acoustic noise in order to record clean acoustic data in deep water). Many of the instruments are drawn from the iXblue catalogue.Real-time data acquisition and processingData from the FeliX’s sensors are recorded and analysed by operators in the boat’s dedicated control room immediately aft of the bridge, then transmitted to a shore facility. “The FeliX can acquire and process data around the clock and return results within 24 hours. The client can validate the results in real time so that charts can be made available as soon as the boat docks. Very few service providers in this field can say the same,” says Carole Chaize, head of iXblue’s coastal engineering team. © IXBLUE Operators supervise data acquisition and processing in the survey room (© iXblue) A Mediterranean startTaking advantage of the fact that she was built and commissioned in the Mediterranean, the FeliX undertook some opportunity work beginning with an acoustic survey and operations for a campaign to investigate a long-standing issue involving the release of red sludge (aka red mud or bauxite tailings). The boat’s bottom corer and deep-water sediment sampler (> 1000m) proved extremely useful for this work.MRE surveys farther northThe FeliX was designed from the outset for operations in the Atlantic, the Channel and the North Sea. After spending her first few months in the Mediterranean, she headed for the French Atlantic coast in January 2017. Since iXblue had already earned a solid reputation for survey work for windfarm and tidal turbine projects, the FeliX was put to work off Guérande, Le Croisic, Fromveur, Saint-Brieuc, Paimpol-Bréhat, Raz-Blanchard, Fécamp and Le Tréport. The FeliX thus worked on most of the marine renewable energy (MRE) sites under development between Oléron and Dunkerque. More recently, the boat added to earlier survey work at the SEM-REV test site off Le Croisic and at windfarm sites off the Normandy and Channel coasts. The work has included geophysical surveys and environmental monitoring as well as unexploded ordnance, or UXO, campaigns. In former theatres of intense warfare, it is essential to ensure that MRE sites and cable routes from the sites to shore are free of unexploded ordnance. UXO campaigns have become an iXblue speciality. The group has developed dedicated algorithms and equipment and routinely deploys a variety of sensors, including a side-scan sonar, a magnetometer, a gradiometer, a multibeam echo sounder and a sediment sampler, each of which contributes useful and sometimes vital data. “Multi-sensor surveys provide input data for the type of detailed analysis required to discriminate between, say, old bombs and certain rocks, like granite, that have a magnetic signature. The position data provided by the iXblue systems is also essential for the divers or ROVs assigned to neutralise duly identified UXOs. In fact, it’s precisely because of the reduced visibility in water that it’s important to know exactly where each device is,” says David Vincentelli, hydrographer and sales engineer with iXblue’s Sea Operations division.Spot contracts tooBetween two MRE contracts, the FeliX found itself in the right place at the right time to pick up additional work. Following the pattern set earlier in the Mediterranean, several missions involved acoustic tests on new military and civilian hardware combined with the collection of performance data for new improved iXblue inertial platforms. Recently, the boat also completed an environmental monitoring campaign focusing on sedimentation and bathymetry at the Pilier aggregate extraction site off the Vendée coast to quantify seabed changes since the last study in 2012.Between major long-term contracts, the FeliX can take on shorter detailed charting missions to help contractors prepare for maritime engineering projects. “This is the only privately owned French-registered boat of its type that is always equipped and ready for geophysical survey work. It’s also the only one that is permanently based on France’s Atlantic, Channel and North Sea coasts. One result — and a new adventure for us — is that the FeliX is available for spot contract work. This means that in addition to our major clients, we can also give others, often on much smaller budgets, access to our boat, as it’s already in the vicinity,” says David Vincentelli. © IXBLUE Launching a magnetometer (© iXblue) Targets metThe FeliX is smaller than the 37-metre Ixplorer, now sold, that it replaces. Being smaller has its advantages. “The FeliX’s modern design offers ample space and excellent capabilities despite her modest size and shallow draught ensuring her suitability for coastal work.” © IXBLUE On deck, ready to lay a buoy(© iXblue) iXblue’s new hydrographic catamaran has certainly been busy over the last 18 months. The management team is particularly happy with the boat and its equipment. “The FeliX has met the targets we set. By building a boat around a set of geophysical instruments, we have succeeded in creating a tool that contributes to the economy by offering quality services combining high performance in navigation, positioning and data acquisition. Although this versatile resource was designed mainly to meet the needs of the MRE community, its powerful lifting gear means it can also perform a range of other missions, like gathering of seabed samples in deep water,” say Carole Chaize and David Vincentelli. © IXBLUE The FeliX off Dunkerque (© iXblue) Original by Vincent Groizeleau published on 24 November 2017. Translated and adapted by Steve Dyson.