Naval Architecture
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Naval Architecture
Boats have played an integral role in the development of commerce and recreation on the Bay. The challenge for today’s designers is to develop more efficient recreational and fishing boats and a ferry system that can compete with our overtaxed highway system.
Basic naval architecture principles are explored, along with a history of boats on the Bay. Students will be introduced to careers in designing, building, operating and maintaining boats and ships.
Naval Architecture
Two-SailBateauE.C.COLLIER,ChesapeakeBayMari=meMuseum,SaintMichaels,MD[h#ps://www.loc.gov/item/md1203/]
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Boats of the Chesapeake Skipjacks
Theskipjackisauniquetypeofcommercialwoodensailingvessel,usedformorethan100yearstodredgeoystersfromtheChesapeakeBay.
Attheheightoftheoysterharvestperiodinthelate1800s,theregrewaneedforshallow-draJsailingvesselsfordredging,thathadalowfreeboard(deckclosetothewaterline)toeasehaulinginthedredges,thatwereeasiertobuildandcrewthanschooners.SkipjacksdredgingundersailontheChoptankRiverin1989.DaveHarp
[h#p://www.firstlightworkshop.com/previous-workshops/chesapeake-bay-2005/]
Skipjacksgenerallyrangedfrom30to60feetondeckandcouldcarry100to500bushelsofoysters.
Naval Architecture
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Boats of the Chesapeake Skipjacks
CrewmemberspullanoysterdredgeinTangierSoundoftheChesapeakeBaynearDealIsland,Md.,in2013.PatrickSemansky/AP
[h#p://theRmes-tribune.com/polopoly_fs/1.2065126!/image/image.jpg_gen/derivaRves/landscape_700/image.jpg]
Skipjackshaveasharpchineandshallow,dead-risehullwithacenterboard.Thelargemainsailprovidesenoughpowertohaulthebigoysterdredges.Aself-tendingjiballowsthecrewtoconcentrateondredging.
Theskipjackwassosimpletobuildthatevenhousecarpenterscouldconstructone.Asaresult,hundredsofskipjackswerebuiltinthe1890sandduringtheirheydaytherewereasmanyas2000skipjacksontheBay.
The117-year-oldRebeccaT.RuarkistheoldestvesselintheChesapeake
BaySkipjackFleet.CraigCaldwell
[h#p://fineartamerica.com/featured/skipjack-rebecca-t-ruark-
craig-caldwell.html]
TheskipjackbecametheMarylndStateBoatin1985.[h#p://www.mdsg.umd.edu/topics/skipjacks/skipjacks]
Naval Architecture
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Boats of the Chesapeake Skipjacks
• AdaFears.Ridge,MD.BuiltinOxford,Marylandin1968.• CalebW.Jones.Builtin1953.• CityofCrisfield.DealIsland,Maryland.BuiltinReedville,
Virginiain1949.• CityofNorfolk.Norfolk,Virginia.BuiltinDeale,Marylandin
1900.• ClaudM.Somers.Reedville,VA.BuiltinAccomackCounty,VA
in1911.• DeeofSt.Mary’s.St.GeorgeIsland,MD.BuiltinPineyPoint,
Marylandin1979.• E.C.Collier.St.Michaels,MD.BuiltinDealIslandin1910.• Elsworth.Worton,MD.Builtin1901.• FannyL.Daugherty.DealIsland,MD.BuiltinCrisfield,
Marylandin1904.• F.C.Lewis,Jr.WestDenton,MD.• FloraA.Price.WestDenton,MD.Builtin1910.• HelenVirginia.BuiltinCrisfield,Marylandin1948.• HildaM.Willing.TilghmanIsland,Maryland.BuiltinOriole,
Marylandin1905.• H.M.Krentz.TilghmanIsland,MD.BuiltinHarryhogan,
Virginiain1955.• IdaMay.DealIsland,MD.BuiltinUrbanna,Virginiain1906.• JoyParks.St.Mary’sCountyPineyPointMuseum.Builtin
1936inParksley,Virginia.
• Kathryn.TilghmanIsland,Maryland.BuiltinCrisfield,Marylandin1901.
• LadyKaKe.Cambridge,MD.BuiltinWingate,Marylandin1956.
• MaggieLee.WestDenton,MD.BuiltinPocomokeCity,Marylandin1908.
• MamieA.Mister.TilghmanIsland,MD.BuiltinDealIsland,Marylandin1911.
• MarthaLewis.HavredeGrace,MD.BuiltinWingate,Marylandin1955.
• MinnieV.BalRmore,MD.BuiltinWenonah,Marylandin1906.• Nathan.Cambridge,MD.BuiltCambridge,Marylandin1992.• NellieL.Byrd.TilghmanIsland,MD.BuiltinOriole,Marylandin
1911.• RebeccaT.Ruark.TilghmanIsland,MD.BuiltinTaylorsIsland,
Marylandin1886.• RosieParks.St.Michaels,MD.BuiltinWingate,Marylandin
1955.• Sigsbee.BalRmore,MD.BuiltinOriole,Marylandin1901.• StanleyNorman.Annapolis,MD.Builtin1902.• Somerset.DealIsland,MD.BuiltinReedville,Virginiain1949.• ThomasClyde.TilghmanIsland,MD.BuiltinOriole,MDin
1911.• VirginiaW.PortKinsale,VA.BuiltinGuilford,Virginiain1904.• WilmaLee.Kinsale,VA.BuiltinWingate,MDin1940.
h#p://oystercatcher.com/skipjack-history/
RemainingSkipjacks
Naval Architecture
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Boats of the Chesapeake Deadrise Workboats
Thedeadrisedesignwasdevelopedaroundthe1880s.DeadrisereferstotheV-shapedbo#omatthebowandmoregenerallytheangleformedbetweenthekeelandthethewaterline.
AV-bo#omiseasiertobuildthanaroundbo#om.TheseboatshaveadraJoftwotothreefeet,makingthemidealfortheshallowsoftheBay.Theaveragedeadriseworkboatis35to45feetlongwithabeamof9to12feet.
TypicalDeadriseHullForm[h#p://blog-imgs-54.fc2.com/b/o/a/boat262/Deadrise-Boat-
Plans-2.jpg]
Genera=onsofindependentfishermenhaveworkedthewatersoftheChesapeakeBayondeadriseboats.[h#p://www.mdsg.umd.edu/topics/watermen/watermen]
Naval Architecture
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Boats of the Chesapeake Deadrise Workboats
SomedeadriseboatsoftheBay[h#p://www.deadrise4sale.com/]
ThedeadriseworkboatisusedbymostwatermenontheChesapeakeBay.Theseboatsaccommodatetheheavy,bulkyequipmentusedforharvesRngavarietyofcatches.
Thedeadrise'ssizeandcapacityallowthewatermantotravelfartheracrosstheBayandcarrymoreseafoodbacktomarket.
VirginiadesignatedtheclassicChesapeakeBaydeadriseworkboatastheofficialstateboatin1988.
Naval Architecture
Typicalsailinglogcanoesailplan[h#p://msa.maryland.gov/megafile/msa/stagsere/se1/se5/029800/029843/pdf/
msa_se5_29843.pdf]
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Boats of the Chesapeake Sailing Log Canoes
OriginallybuiltbythenaRvePowhatantribesfromasinglelog,theseboatswereadoptedbyearlyEnglishse#lerswhodiscoveredthatthesturdycraJcouldhandletheroughwatersoftheBayandcarryaheavyload.
TheEnglishse#lersaddedasailtoincreaseitsspeed.ThecanoewasthestandardworkboatontheBayunRlthe1900s.
Duringthesummermonthsmanywatermenturnedtheirsailingcanoesintoracingboats.Theracingcanoehaslargersailsandhikingboards,allowingthecrewtokeeptheboatupright.
photobyBillKepner[h#p://www.logcanoegallery.com/fleet.html]
Naval Architecture
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Boats of the Chesapeake Sailing Log Canoes
LogcanoeracinghasbecomeatradiRonontheBay.TheracestakeplaceontheMilesRiver,theTredAvonandtheChesterRiveronMaryland'sEasternShore.
AccordingtotherulesoftheChesapeakeBayLogSailingCanoeAssociaRon,theonlypenaltyforsailareaisaninabilitytokeeptheboatupright.
h#p://www.sailmagazine.com/racing/rega#as/an-adventure-with-chesapeake-bay-log-canoe-sailors/
h#p://cbmm.org/tags/log-canoe/
Naval Architecture
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Boats of the Chesapeake Sailing Log Canoes
Fewerthantwodozenlogcanoesremain,mostofthembuiltinthelate19thandearly20thcenturies.AllhavereRredfromtheirworkingcareers.AbouthalfsRllacRvelyrace.
ListoflogcanoesontheNaBonalRegisterofHistoricPlaces
• BillieP.Hall,TalbotCounty,Maryland• EdmeeS.,TalbotCounty,Maryland• FlyingCloud,TalbotCounty,Maryland• IslandBird,TalbotCounty,Maryland• IslandBlossom,TalbotCounty,Maryland• IslandImage,KentCounty,Maryland• IslandLark,TalbotCounty,Maryland• JayDee,TalbotCounty,Maryland• Magic,TalbotCounty,Maryland
• Mystery,QueenAnne'sCounty,Maryland• Noddy,TalbotCounty,Maryland• Oliver'sGiS,AnneArundelCounty,Maryland• Patricia,DorchesterCounty,Maryland• Persistence,TalbotCounty,Maryland• Rover,TalbotCounty,Maryland• Sandy,TalbotCounty,Maryland• S.C.Dobson(MaryJuliaHall),KentCounty,Maryland
• SilverHeel,KentCounty,Marylandh#ps://en.wikipedia.org/wiki/Log_canoe
Naval Architecture
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Boats of the Chesapeake Ferries
Therewereferryboatsonthebayaslongagoasthe17thcentury,withoneoftheoldestandmostheavilytraveledroutesrunningthe25milesbetweenRockHallandAnnapolis.
In1919,ferriesbegantransporRngautomobiles,freightandpassengersbetweenClaiborneandAnnapolis.
h#p://fineartamerica.com/featured/old-bay-line-of-balRmore-1877-daniel-hagerman.html
TheFloridawasbuiltfortheBalRmoreSteamPacketCompany,whichstarRngin1839operatedfor122yearsontheBay.ItranthelastsurvivingovernightsteamshippassengerserviceintheUnitedStates.
TheOldBayLineshipthePresidentWarfieldranbetweenBal=moreandNorfolk[h#p://darkroom.balRmoresun.com/2015/03/from-the-vault-175th-anniversary-of-the-old-bay-line/#16]
Naval Architecture
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Boats of the Chesapeake Ferries
h#p://www.stardem.com/news/arRcle_c1275235-b86f-51f5-aa78-8cf4dbb0b6e7.html
DespitecompeRRonfromthenewlyopenedBayBridge,unRl1952,ferriessRllmanagedtotransportmorethanamillionpassengersayear.Theboatsran46roundtripsaday.
h#p://www.stmichaelsmd.org/list/member/oxford-bellevue-ferry-384
Establishedin1683,theOxford-BellevueFerry,believedtobethenaRon'soldestprivatelyoperatedferryservice.
Newpassengerhydrofoildesignsthata#ainspeedsof35-50knotshavebeenproposedforcommutersandtourists.
h#p://www.foils.org/01_Mtg_Pres%20dnloads/100311%20IHS%20diner%20mtg/100311MarkRiceMAPPIHS.pdf
Naval Architecture
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Boats of the Chesapeake Commercial Ships
Virginiaishometo"America'sFirstPort,"establishedatJamestownin1607andalsohostedtheeraofthegreatclipperships.
Inthe17thcentury,thePortofBalRmoresupportedtobaccotradewithEngland,butsoonothercommodiResshippedthroughitsnaturalharbor.BothoftheseportsontheChesapeakeBayhaveevolvedintomajorshippingterminals.h#p://www.virginiaplaces.org/transportaRon/graphics/eastcoastports.png
AbulkcarrieratanchoroffAnnapoliswai=ngtoloadcargoinBal=more
MarylandandVirginiapilotshelpvesselsincludingcargoships,tankers,andcruiseshipsreachtheirdes=na=onssafelybyboardingthoseshipsfromasmallerboatandthennaviga=ngthemintoport.[h#p://buoybay.noaa.gov/featured-users/ben-schill]
Naval Architecture
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Boats of the Chesapeake Commercial Ships
h#p://boards.cruisecriRc.com/showthread.php?t=203217
In2015,morethan90cruisescarrying193,709passengersdepartedfromBalRmore,whichrankedsixthinEastCoastports,eleventhinU.S.ports,andtwenRethinworldports.
h#p://www.mdsg.umd.edu/sites/default/files/files/keepclear.pdf
TheChesapeakeBaysupportsahealthytugandbargecommodi=estransporta=onindustry
Naval Architecture
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Boats of the Chesapeake Coast Guard and Navy Shipyards
TheaircraJcarrierhasplayedasignificantroleinAmerica'snaRonaldefenseforover80years,extendingourmilitaryreachbeyondwhatwaspreviouslypossible.
NewportNewsShipbuildingisacommercialshipyardthathasbeeninvolvedintheevoluRonofU.S.aircraJcarriersandsubmarines.
TheCurRsBayCoastGuardYardwasestablishedin1899asaCoastGuardtrainingacademyandboatrepairstaRon.By1910,theCGYwasanoperaRonalshipbuildingandrepairfacility.
TheyardreacheditspeakemploymentduringWorldWarII(1941-45),withaworkforceofover3,000.
Naval Architecture
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Boats of the Chesapeake Recreational Boats
Thereareapproximately212,000registeredboatsinMarylandand238,000inVirginia.ThemajorityoftheseboatsoperateontheChesapeakeBayoritstributaries.AccordingtotheChesapeakeBayPowerBoatAssociaRon,over80percentofallboatsregisteredontheBayarepowerboats.
Hydroplanesraceatthe106thrunningoftheCambridgeClassicontheChoptankRiver[h#p://www.proptalk.com/the-cambridge-classic/]
Ara\-upontheMagothyRivershowsanicemixofpowerandsail.[h#p://www.boatus.com/magazine/2012/June/a-burgee-and-an-idea.asp]
J/70sarepartofthe200boatsintheAnnapolisNOODrega`a[h#p://www.sailfeed.com/2015/05/annapolis-nood-preview-2/]
Naval Architecture
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Why Do Boats Float?
Archimedes,wholivedfrom287BC-212BC,discoveredthat“abodyimmersedinaliquidoragashasabuoyantforceequaltotheweightoftheliquidorgasthatitdisplaces”whenheenteredabathtub.Excitedabouthisdiscovery,heranthroughthestreetsofSyracuseyelling“Eureka”
h#p://www.kusadasi.tv/archimedes.html
AshipthatislaunchedsinksintotheoceanunRltheweightofthewateritdisplacesisjustequaltoitsownweight.Astheshipisloaded,itsinksdeeper,displacingmorewater,andsothemagnitudeofthebuoyantforceconRnuouslymatchestheweightoftheshipanditscargo.
h#ps://www.britannica.com/science/Archimedes-principle
h#ps://dbf-blockii-boatbuilding.wikispaces.com/Archimedes
+Principle
Naval Architecture
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Why Don’t Boats Tip Over?
SailboatheelingoverinaHiker-YachtRaceontheDelawareRiver,1870s
AnyfloaRngbodyissubjectedbytwoopposingverRcalforces.Oneisthebody'sweightW,whichisdownward,andtheotheristhebuoyantforceBF,whichisupward.TheweightisacRngatthecenterofgravityGandthebuoyantforceisacRngatthecenterofbuoyancyBO.
Boatstragicallyoverloadedwithrefugeesareunstablebecausethecenterofgravityistoohigh.[h#p://www.aljazeera.com/mritems/Images/
2016/5/26/8bd4ec05e6ea41de98d4e73cde827eb4_18.jpg]
Naval Architecture
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Why Don’t Boats Tip Over?
Asashipheelsoverthecenterofbuoyancy,BOisshiJedbecauseawedgeofwaterisimmersedononesideandemersedontheother.
TheshipmayRltfrommanycauses,likewindorwaveacRoncausingthecenterofbuoyancytoshiJtoanewposiRonBO'asshownbelow. TheCougarAce=ppeda\erherballastwasadjusted
intheopensea[U.S.CoastGuard]
TheKoreanferryMVSewolcapsizedin2014,killing304people.Anunreasonablysuddenturnand
overloadingcausedthecapsizing.[SouthKoreanCoastGuard]
Naval Architecture
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What Makes a Powerboat Move?
Energysourcesusedtopropelboatsare:• Fossilfuels(gasoline,diesel,naturalgas)• Renewableenergy(wind,solar)• Humanpower-rowing
Thecurrentpowerboatspeedrecordof318mphwassetin1978byAustralianKenWarby,inawoodenhebuiltinhisbackyard[h#p://
www.digitaltrends.com/cool-tech/fastest-boat-in-the-world/]
Weighinginat131tons,thispropellerdrivestheEmmaMaersk,acontainershipwithaloadcapacityofupto14,770twenty-footcontainers,alengthof397m.[h#p://www.marineinsight.com/
tech/8-biggest-ship-propellers-in-the-world/]
Avessel'spropellerworksbythrusRngacolumnofwaterawayfromthehull,producingareacRveforcethatmovestheboatforward.
h#p://www.pointwise.com/theconnector/May-2014/Propeller-Blade-Loads-with-
OpenFOAM.shtml
Naval Architecture
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What Makes a Sailboat Move?
In2012,theVestasSailrocketIIachievedaspeedofover65knots(75+MPH)[h#p://www.sailrocket.com/]h#ps://astarmathsandphysics.com/a-level-physics-notes/173-forces-and-
moRon/2788-how-sails-work.html
AccordingtoBernoulli’sPrinciple,whenwindcomesincontactwiththefrontofsail,theairsplitsupandsomeairtravelsoverthesailandsometravelsunderthesail.Airtravellingoverthesailhasafurtherdistancetogosoinordertomeetbackupwiththesameairatthetrailingend,itmusttravelfaster.ThiscreatesalowpressureareaoraliJforce.
Naval Architecture
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What Makes a Human-Powered Boat Move?
h#ps://www.britannica.com/topic/rowing-boat-propulsion-and-sport
h#p://www.seabreeze.com.au/ArRcles/Stand%20Up%20Paddle/Beginners-guide-to-improving-your-SUP-paddling_5591958.aspx
• Eight-personrowingshellscanobtainspeedsof18mph.
• OnDecember26,2015,JohnBeeden,53,becamethefirstpersontosuccessfullyrownon-stop,unassistedfromNorthAmericatoAustraliacovering7400nauRcalmilesin209days.
• In1896,FrankSamuelsenandGeorgeHarborowedfromManha#antoEnglandin55daysand13hours,covering3,250miles.
h#p://oarnorthwest.com/2013/02/daily-educaRon-update-2-1-harbo-and-samuelsson/
Naval Architecture
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What Slows a Boat Down?
ComponentsofTotalHullResistance
Theresidualresistanceisduetopressuresdevelopedinpushingthewateraside,andarisesfromtheformofthehull.
Theairresistanceofashipalsoslowsitdown.
h#p://www.humphree.com/learn-more/how-it-works/
Theresistanceofferedbyashiptomovementthroughwatermayberesolvedintotwoprincipalcomponents:fricRonal(viscous)resistanceandresidual(wavemaking)resistance.
ThefricRonalresistancearisesfromfricRonalforcessetupbytheflowofwateralongthesurfaceofthehull,andisconsequentlyinfluencedbyfouling(barnacles).
Naval Architecture
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What Slows a Boat Down?
W.Froude'ssketchofcharacteris=cbowwavetrain[h#p://www.ebah.com.br/content/ABAAAg1k0AL/principles-of-naval-
architecture-vol-ii-resistance-propulsion-and-vibraRon?part=6]
WilliamFroudeshowedthatthewaveeffectsofscaleshipmodelstowedinatankwouldresembleactualshipsifthevelocitywasreducedinproporRontothesquarerootofthelength. WilliamFroude(1810-1879)
Computa=onalFluidDynamics(CFD)isnowusedtopredicttheresistanceofshiphulls[h#p://cflymarine.com/services/]
BoatinUSNATowingTank[h#ps://www.youtube.com/watch?v=YXCU_mCuI8g]
Naval Architecture
Length-to-Beamra=oofsomesailboats[h#p://sailingmagazine.net/arRcle-1218-comparing-boats.html]
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Efficient Boats
AccordingtonavalarchitectDaveGerr,thethreebasicthingsthatmakepowerboatsmoreefficientare:
1. Long,slenderhulls2. Goingslower3. Anefficientpropulsionpackage
WecanaddlightweightconstrucRontothatlist.
Limitedstabilityreducestheviabilityofverylong,narrowboathulls.Catarmaransandtrimarans(mulRhulls)overcomethischallengeandareeasilymovedthroughthewater.
SincemulRhullsareverynarrow,theyareveryweightsensiRvesoaretypicallybuiltusinglightweightmaterials.ThedisplacementcatamaranHoloHolois62’long,weighsabout25,000lbs,hasa
pairof440hpenginesandoperatesinsomeofthemostseverewatersintheUS.[h#p://www.mulRhulldesigns.com/pdf/powercatslt.pdf]
Naval Architecture
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Efficient Boats
Shu`leworthDesigns"Adastra"is42.5meterslongandhasatopspeedof23.2knots[h#p://www.shu#leworthdesign.com/adastra-arRcle-part1.html]
Thecenterhulloftrimaranshavenoinherentstability-allthestabilityiscreatedbytheoutriggers.ThesevesselscanachievelengthtobeamraRosinexcessof17,whichhasbeenshowntosignificantlyincreasefuelefficiency
TuranorPlanetSolaristheworld'slargestsolar-poweredboat[h#p://www.bbc.com/news/business-23936775]
TodemonstratethepotenRalofsolarpower,thePlanetSolarcircumnavigatedtheglobe(60,000kmor37,000miles)usingenergyharnessedfrommorethan500squaremetersofsolarpanelstodrivetwo60kWelectricengines.
Naval Architecture
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Efficient Boats Electric Propulsion
TheAmpereisthefirstall-electricba`ery-poweredcarandpassengerferryintheworldandcarries120carsand360passengersatabout10knots
[h#p://cleantechnica.com/2015/06/13/worlds-first-electric-ba#ery-powered-ferry/]
Elcoelectricmotorandba`eries[h#p://www.elcomotoryachts.com/elco-ep-motor-benefits.shtml]
Elco’shistorydatesbacktothe1893ChicagoWorld’sColumbianExposiRon,whereitintroduced55electriclaunches.Todaythecompanyoffersbothinboardandoutboardelectricmotors.
Benefitsofelectricpowerinclude:• Noexhaustfumesproduced• SilentmotoroperaRon• Cruisealldayandchargetheba#eriesovernight
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Boat Design Questions
• Whydoesapieceofsteelsinkinwaterandmeanwhileaboatmadeoutofsteelcanfloat?
• Whydoesn’tasailboatRpoverwhenwindblowsagainstthesail?
• Howdoesasailboatsailintothewind?
• Whichtypeofboatmoveseasierthroughthewater,anarrowboatorawideboat?
• Whichtypeofboatismorestable,anarrowboatorawideboat?
• Whattypesofenergysourcescanbeusedtomoveboats?
• Ifyoucouldgoanywhereintheworldinaboat,wherewouldyougo?Whattypeofboatwouldyouuse?
Naval Architecture
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Bay Challenges
• WhatwouldaworkboatfortheBaythatuseslessenergythantradiRonaldeadriseboatslooklike?
• ArepassengerferryroutesthatexistedontheBay100yearsagoviabletoday?Whatwouldtheseferrieslooklike?
• HowcanwereducethecarbonfootprintfromcommercialshippingontheBay?
• WhattypesofrecreaRonalboatsaremoreefficientthanspeedboatsandcabincruisersthatarepopularonthebay?
• Howcanweaccommodatemorehuman-poweredboatsontheBay?
• WhattypesofjobsrelatedtoboatsandshipsontheBaylookliketheywouldbefunandagoodwaytomakealiving?