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1、Historyofaviation[11ThediscoveryofthekitethatcouldflyintheairbytheChinesestartedhumansthinkingaboutflying.KiteswereusedbytheChineseinreligiousceremonies.Theybuiltmanycolorfulkitesforfun.Moresophisticatedkiteswereusedtotestweatherconditions.Kiteshavebeenimportanttotheinventionofflightastheywereth
2、eforerunnertoballoonsandgliders.[2]Forcenturiesmanhasdreamedtosoarwiththebirds.FamousinventorssuchasLeonardodaVinci,JohnStringfellow,andLawrenceHargravehaveconjuredupideasofhowtogetsomeofthestrangestmachinestoflylongbeforetheWrightbrothers9famousfirstflightatKittyHawk.[3]Thefirstformofanaircraft
3、wasthekite,designedinthe5thcenturyBC.Lateroninthe13thcentury.RogerBacon,anEnglishmonk,performedstudieswhichlatergavehimtheideathataircouldsupportacraftjustlikewatersupportsboats.Inthe16thcentury,LeonardodaVincistudiedbirdsflight,andlaterproducedtheairscrewandtheparachute.Theairscrew,leadingtothe
4、propellerlateron,andtheparachuteweretremendouslyimportantcontributionstoaviation.Heenvisionedthreedifferenttypesofheavier-than-aircraft:thehelicopter,glider,andornithopter(amachinewithmechanicalwingswhichflaptomimicabird).AlthoughLeonardo'sdesignswereimpractical,seeingtheyrequiredhumanmuscularpo
5、werwhichwasinsufficienttogenerateflightwiththeaircraftheenvisioned,hewasvitaltoaviationbecausehewasthefirsttomakescientificsuggestions.[4]Someofthemorecredibledevelopmentsinactualflightandstabilityoccurredinthe19thcentury.BritishSirGeorgeCayleydesignedacombinedhelicopterandhorizontallypropelleda
6、ircraft,andBritishFrancisHerbertWenhamusedwindtunnelsinhisstudiesandpredictedtheapplicationofmultiplewingsplacedaboveeachothe匸AnotherfamousinventorwasJohnStringfellow,whodesignedasteamenginepoweredaircraftwhichwaslaunchedfromawire.Thismodeldemonstratedliftbutfailedtoactuallyclimb.LawrenceHargrav
7、e,aBritish-bornAustralianinventor,createdarigid-wingaircraftwithflappingbladesoperatedbyacompressed-airmotor,itflew312fit(95m)in1891.Afamousgliderdeveloperinthe19thcenturywasJeanMarieLeBris,aFrenchmanwhotestedagliderwithmova