空中领航学(E-01)

AirNavigation空中领航学1AirNavigation课件制作课程讲授王惠民AirNavigation空中领航学2Flight,orairnavigationisthemeansbywhichpilotsreachtheirdestinationandfindtheirexactlocationatanytime.AirNavigation空中领航学3空中领航学是引领飞机航行的一门应用学科，它以地球作为参照系来研究飞机相对于地球的运动及其导航方法。空中领航学所要解决的三大基本问题，是确定：飞机位置飞机航向飞行时间AirNavigation空中领航学4空中领航学研究的主要内容：领航基础及元素；领航原理和方法；领航设备工作原理和使用；领航误差及修正原理；领航准备和实施。AirNavigation空中领航学5AirNavigation空中领航学6本课件(共九章)系根据西澳教材AnAviationTheoryCentreManual-MeteorologyandNavigation，即ThePilot’sManual系列丛书第二册制作，仅供课堂教学使用。特此申明，谨向该书编者致谢。AirNavigation空中领航学7Chapter1FundamentalsofAirNavigationBasicPrinciplesThebasicprinciplesofairnavigationapplytoallaircraft,fromthesimplesttrainerstothemostsophisticatedpassengerjets.Whenflyingcross-country,youarethepilot,thenavigatorandtheradiooperator.你既是驾驶员,也是领航员，又是无线电通信员。BasicPrinciplesAirNavigation空中领航学8Asapilot,youmustaviate,navigateandcommunicate.AirNavigation空中领航学9TypesofNavigationThebasicmethodofnavigationinVFR(day)operationsismapreading,whichisvisual-contactnavigation.Itrequiresmoreorlesscontinuousvisualreferencetothegroundandisthereforeoflimitedvalueinpoorvisibilityconditionsorwhennavigatingaboveextensivecloudcover.TypesofNavigationThebasicmethodofnavigationinVFR(day)operationsismapreading,whichisvisual-contactnavigation.Itrequiresmoreorlesscontinuousvisualreferencetothegroundandisthereforeoflimitedvalueinpoorvisibilityconditionsorwhennavigatingaboveextensivecloudcover.TypesofNavigationAirNavigation空中领航学10Toassistuswithourvisualnavigationprocedures,wecanuseanyradionavigationequipmentinstalledinouraeroplanetoobtaininformationfromground-basedradiobeacons.Tosupportvisualnavigationprocedures,weusedeadreckoning(DR)todeduceourposition.Toassistuswithourvisualnavigationprocedures,wecanuseanyradionavigationequipmentinstalledinouraeroplanetoobtaininformationfromground-basedradiobeacons.Tosupportvisualnavigationprocedures,weusedeadreckoning(DR)todeduceourposition.AirNavigation空中领航学11FormoftheEarthAllairnavigationisdonewithreferencetothesurfaceoftheearth.ForpracticalpurposetheearthcanbetreatedasaperfectspherewithanaveragediameterofR=6371.004km.ShapeandSize地球半径：RAirNavigation空中领航学12RotationoftheEarthPolaraxisTruesouthTruenorthTheearthrotatestowardtheeast.极轴66º33’AirNavigation空中领航学13ImaginaryLinesontheEarth’sSurfaceGreatCircles大圆Agreatcircle(GC)drawnontheearth’ssurfacehasaplanewhichpassesthroughthecentreofthesphere(earth).大圆以地球的球心为其圆心。经线赤道无线电信号AirNavigation空中领航学14GreatcircleSmallcircleAirNavigation空中领航学15大圆具有如下特点：•大圆是在球体表面上所能画出的最大的圆；•在球体表面两点之间的最短距离是大圆的弧；•除了像地球的地理两极（径向相反）的两点以外，在球体表面上两点之间只能画出一个大圆。AirNavigation空中领航学16SmallCircles小圆Asmallcircleisanycircleonthesurfaceofaspherethatisnotagreatcircle;thatis,thecentreofasmallcircleisnotatthecentreoftheearth.在地球表面上除大圆以外的圆，其圆心不是球心。Theplaneofasmallcircledoesnotpassthroughthecentreofasphere.小圆平面不通过球心。球心圆心AirNavigation空中领航学17Latitude纬度南极北极赤道AirNavigation空中领航学18Latitude纬度AirNavigation空中领航学19Longitude经度南极北极本初子午线(0°经线)英国伦敦格林威治皇家天文台AirNavigation空中领航学20Longitude经度AirNavigation空中领航学21PositionontheEarthTheusualmethodofspecifyingtheexactpositionofanypointonearthisbyreferencetoimaginarylinesofformingthelatitudeandlongitudegridonthesurfaceoftheearth.参照地球表面的纬度和经度网格,可为地球上任何一点精确定位。φλ例如:北京39º57´N,116º28´EAirNavigation空中领航学22Themorecommonlymethodstopasspositioninformationbyradioincludethefollowing:▪Statingapositionasover(过)orabeam(切)alandmarkoranavigationaid;and▪Statingthedistance(距离)andbearing(方位)ofanaircraftfromalandmarkoranavigationaid.Alternativemethodsforspecifyingaircraftposition.AirNavigation空中领航学23DirectionDirectionistheangularpositionofonepointtoanotherwithoutreferencetothedistancebetweenthem.Tomeasuredirection,thefullcircleisdividedinto360º.Itisusualtorefertodirectionasathree-figuregrouptopreventanymisunderstanding.AirNavigation空中领航学24BeechcraftBE-55PiperP28ACessnaC150Themostfundamentalreferencefromwhichanglesaremeasuredisthatoftruenorth,from000ºTthrough090ºT,180ºT,270ºTto360ºT.AirNavigation空中领航学25NMAirNavigation空中领航学26·Agreatcirclecrossessuccessivemeridiansatagraduallychangingangle.·Arhumblinecrossesallmeridianslongitudeatthesameangle.Inpracticalterms,thegreat-circledirectionandtherhumb-linedirectionmaybeconsideredtobethesameovershortdistances,saylessthan200nm.AirNavigation空中领航学27TrueDirectionWhenwemeasuredirectionbyreferencetothelocalmeridian,weareusingthenorthgeographicpoleortruenorthasthereference.Thisdirectionisreferredtoastruedirection.Directionismeasuredfromameridian.AirNavigation空中领航学28MagneticDirectionTheactualdirectionshownbyafreelysuspendedmagnetiscalledmagneticnorth,andthisisthedatumweusetomeasuremagneticdirection.Theearth’smagneticfield.AirNavigation空中领航学29Variation磁差Variationistheangulardifferencebetweentruenorthandmagneticnorth.Variationeast,magneticleast;variationwest,magneticbest.AirNavigation空中领航学30地球磁场磁差AirNavigation空中领航学31Isogonalsandtheagonicline.AirportPERTHJANDAKOT32º5´51S115º52´52EMagVar:1.483°WU.S.A.AustraliaAirNavigation空中领航学32AirNavigation空中领航学33RelativeBearings相对方位角Therelativebearingofanobjectfromanaeroplaneisitsangulardistancefromtheaircraft’sheadingmeasuredclockw