仪表飞行员地面课程Lesson5

SierraAcademyofAeronauticsIRGroundLesson5PrecisionApproach'sPrecisionApproachesProvidelateralandverticalguidanceExamples:ILS,MLS,andPARInstrumentLandingSystem(ILS)BasicGroundComponentsoftheILS:LocalizerGlideSlopeOuterMarkerMiddleMarker(ApproachLightSystem)LocalizerVHFgroundbasedtransmitterthatprovidescourseguidancetotherunwaycenterline.Angularwidthofcoursevariesbetween3and6degrees.Coursewidthatrunwaythresholdisapproximately700feet.Localizersensitivityis4timesgreaterthenVOR.Localizer(cont.)Localizerreceptionisavailabletoatleast18NMfromantennaanduptoanaltitudeof4,500ft.abovetheantenna.Localizer(cont.)Eachdotrepresents½degreeoffcourse.40ILSchannels:108.10–111.95MHz(oddths)Four-letterMorsecodeLocalizerOrientation:Signalonlyrepresentsonemagneticcoursetorunway.OBSDOESNOTaffectcoursetracking.TOFlagpresentregardlessofinbound/outbound,frontcourse/backcourse.Whentrackinginsamedirectionoffrontcourse,propersensing;whentrackingoppositedirectionoffrontcourse,reversesensingoccurs.(179vs.359)WhenusingHSI,musttwistinfrontcoursetoallowcontinuouspropersensing.LocalizerOrientation:GlideSlopeUHFtransmitteris“paired”totheVHFlocalizerfrequency.Providesverticalguidancetoadistanceof10NM.Signalisonly1.4deg.thick,soextremelysensitive.ShouldinterceptGSatrecommendedpublishedaltitudetoavoidfalseGSindications.ILSMarkerBeaconsProviderangeinformationandindicatesignificantpointsintheapproach.ILSMarkerBeacons(cont.)OuterMarker(OM)PlacedatFAFforthenonprecisionapproach/justinsidepointofglideslopeintercept(4-7milesfromrunwaythreshold).Glideslopeisapproximately1,400feetaboveOM.ILSMarkerBeacons(cont.)MiddleMarker(MM)Locatedapproximately3,500feetfromrunwaythresholdandinterceptsglideslopeatapproximately200feetaboveTDZE.ThisusuallycorrespondswithDA,howeverMMisnotaMAP!ILSMarkerBeacons(cont.)InnerMarker(IM)LocatedbetweenMMandrunwaythresholdandindicateswhereglideslopeshouldinterceptdecisionheightforaCATIIapproach.BackCourseMarker(BCM)Located4-7milesfromoppositeendofrunwayandservesasFAFforbackcourseapproach.*OnlyOMisrequiredfortheCATIILS.InoperativeILSComponents

GlideSlopeUseLocalizerminimums.Becomesnonprecisionapproach.LocalizerOTSILSapproachnotauthorized.OuterMarkerOTSILSapproachnotauthorizedwithoutapprovedsubstitute.ApproachLightsOTSILSapproachauthorized,howeverrefertoINOPComponentsTabletodetermineadjustmentstovisibilityrequirements.SubstitutionsforOuterMarkerCompassLocatorPrecisionApproachRadar(PAR)ApproachSurveillanceRadar(ASR)PublishedDMEfixPublishedVORfixPublishedNDBfixSubstitutionsforMiddleMarker:CompassLocatorPrecisionApproachRadar(PAR)VariationsfromtypicalILSapproachCATI,CATII,CATIIISpecialequipment,trainingandcertification?Localizer-TypeDirectionalAid(LDA)Samefrequencyrange,accuracy,anddimensionsMayhaveglideslope,butnotalignedwithrunwaycenterlineVariationsfromtypicalILSapproach(cont.)LocalizerBackCourseApproachUtilizessignalfromlocalizertransmittertoaccommodateadditionalapproachtotheoppositeendofrunwayCannotutilizeglideslope(configuredonlyforfrontcourse)VariationsfromtypicalILSapproach(cont.)SimplifiedDirectionalFacility(SDF