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TheCanadianAssociationofDivingContractors21featureAsignificantcomponentofthedivingindustryisriggingdesigningadeploymentsystemforaninstrumentweighingafewkilogramstoremainstableistypicallyanon-issue.Scanningsonaristhesystemforpositioningadiverinrealtime.Deployingscanningsonarletstheteamidentifytargetsandpotentialhazardsbeforethediverdescends.Oncethediverisonbottomtheoperatorscanstheareaandguidesthedivertotargetsofinterest.Recordingthesonardataverifiestargetinvestigationandareacoverageandprovidesimagesofthesubstructuralelementsandsurroundingseabed.Submittedwiththediverreporttheseimagesestablishanundisputablerecordofthesubstructureconditionduringthesurvey.MonitoringthedivesitewithscanningsonarFittingscanningsonarwithaconicalbeamtransducergivesechosoundprofilingcapabilitywiththeaddedadvantageofscanningthrough360.Unlikeaconventionalsounderthatmustbemovedtoobtainadditionalcoveragethescanningsonarmotorturnstheconicaltransducerthroughthearcofprofilecoverageinterest.Thisopensupapplicationsforscourholeunderdockintakeoutfalldredgeandotherprofileinspectionprojects.Beamanglesapplyingthecorrectspeedofsoundconstantandtargettosonargeometryinfluencescanningsonaraccuracyjustlikeitsside-scanandechosoundercounterparts.Thestrengthofscanningsonaritsmultimodecapabilitywhilegeneratingimagesfromafixedpositionisalsooneofitslimitations.Anymovementtotheheadduringdatacollectiondegradesimagequality.Thefactitispositionedstationarytoobtaintheclearestimagesalsolimitsthespeedofdatacollection.SoitbegsthequestionwhatifanysonarservicesdotodayscommercialdivingcompaniesneedtoofferandwhatfinancialcommitmentdoesittaketoprovidethatcapabilityThereisnooneanswertothesonarservicesorinventoryneededbyacommercialdivingcompany.Themarketpotentialandcompetitiondictatethis.Andbeforemakingthesonarinvestmentunderstandthatgreatsonardatacomesfromtrainingandsystemfamiliarizationthebestoperatorsinthesonarbusinesshavemadethesecommitments.Timeshavechangedsincethat1984confrontationwiththecrustycommercialdiverandhisattitudethatsonarwastheretoreplacehisjob.Theneedtogetadivertotheunderwaterworksiteisntbeingalleviatedusingtechnologytomakediverinterventionsaferandmoreefficientistheindustrysdirection.Sonarispartofthatprocess.MarkAthertonisSpecialProjectsManageratKongsbergMesotechLtd.SegmentsofthisarticlearemodifiedexcerptsfromEchoesandImagesTheEncyclopediaofSide-ScanandScanningSonarOperationsbyMarkW.AthertonandanarticlecoauthoredbyMarkW.AthertonandBrianAbbottwhichwasoriginallypublishedinBridgeDesignandEngineeringMagazineissue45.Scanningsonarprofilesdataofaverticalrockshaftwithpreciseshaftdiametermeasurementstodesignalinerandpreventrockfromcalvingandpassingthroughahydroelectricturbine.Deployingthescanningsonarinacageandcollectinghorizontalprofilesatpredeterminedelevationsprovidedthedatasettocompletetheshaftlinerdesign.Scanningsonarimagingbeamcoverage.Augmentingdiverinspectionwithsonarimageryvirtuallyeliminatestheissueencounteredintheseawallinspectionanddiscoveryoftheoutfall.