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Fugros Fresnel Zone Binning approach, can position the streamers to optimize subsurface seismic coverage and minimize infill. Use of lateral steerable birds has also proved successful for 4D purposes, when working in obstructed areas, or when applying new acquisition techniques like shooting in turns or in fan mode. Other benets of the lateral controllers include more ecient equipment deployment and recovery, and safer workboat operations due to improved streamer control. A unique feature of the C-class vessels is the wide- spread use of electrical drives on the winches and handling systems using vector control technology. is gives an accuracy of 0.01% compared to 5% on similar hydraulic installations, which enables precise control during equipment deployment and recovery. It also has proved to have much shorter installation times and fewer operational issues during startup and operation than similar capacity hydraulic installations. e energy source uses up to 84 G guns? and these are deployed on 6 x 20 m long sti gun arrays, which are made from heavy-wall polyethylene pipe of 800 mm diameter with duplex steel structural keel. Control of the source is from the Gun-link 4000 digital distributed system that allows C-class vessels to use gun umbilical cables with 800 m length. is exibility allows Fugro to oer clients reduced inline osets (source to receiver). Communications are maintained to shore through- out the survey by the use of 2 x V sat systems located to ensure communication is maintained on all headings at high latitudes. An additional KU band antenna has also been installed. e entire design of the mast and antenna arrangement has been the subject of a detailed study to make certain the dierent systems do not inter- fere with each other and are able to function correctly. Marine speci?cations e crew accommodation is built with the typically high standards of Norwegian shipyards: 70 single cabins all with private bathroom, a 70 seat cinema/auditorium, fully equipped hospital, a gymnasium to rival most 5-star hotels, and a swimming pool. e bridge is designed and classed according to the NAUT-AW rules, which are intended to improve nautical safety and reduce the risk of failure in bridge operation causing collision, grounding, and heavy weather damage. e integrated helicopter deck, located on the fore part of the ship, is built according to the UK CAP 437 rules for a Sikorsky S92 helicopter. Adjacent to the heli- copter deck is a large and well-equipped hospital that is managed by a professional medic. e main propulsion arrangement is a diesel elec- tric solution, with conventional variable pitch and variable speed propellers. is combination is con- sidered optimal for eciency and underwater noise reduction. C-class vessels have a Bollard pull of greater than 150 tons on the main shafts. e retract- able 360-degree azimuth thruster, installed in the fore part of the vessel, provides additional towing force and improves propulsion redundancy. It can also be used for assisting in turning-in situations with strong cur- rents while towing. The main generator sets use medium-speed engines delivered by either Rolls-Royce or Wärtsilä, and power onboard is managed through a power management and automation system, with operator stations on the bridge console and in the main control room. e automation and power management sys- tems have been evaluated using the enhanced system verication technique known as hardware in loop? testing. is analysis has assisted Fugro in reducing www.sname.org/sname/mt January 2013 e C-class vessel design enables deployment of the largest possible spread of seismic streamers. Fugro Symphony is based on the same hull, machinery, and accommodation design as Fugros other C-class vessels, but Fugro Symphony is out?tted for oshore construction and inspection, maintenance, and repair operations.