空中防撞系统

空中防撞系统TCASContentsIntroductiontoTCASFunctionofTCASTCASAlerAreaTCASInformationPrincipleofTCASTCASComponentsTCASInterfaceTCASSignalformatsTCASDisplayTCAS概述TCASI能够侦测上下7000至10000呎，前后15至40海里，发现有航机接近时，会提前40秒警告飞行员对方飞机的高度和位置。第二代空中防撞系统（TCASII），是目前最被广泛使用的，会用声音及显示警告飞行员，称为ResolutionAdvisory（RA），并且会用语音指示避撞的动作，例如：“Climb！Climb！Climb！”“Descend！Descend！Descend！”。别架飞机若有装TCAS，也会有相反的警告发出来。第三代空中防撞系统（TCASIII），除了有上下避撞措施之外，还增加左右避撞能力。Honeywell公司是唯一一家生产所有类型TCAS的制造商，超过一半的TCAS产品都是出自该公司。ICAO:thecarriageofACASIIhasbeenmandatoryworldwidefrom1-1-2005forallcivilianturbine-enginedaircraftcarryingmorethan19passengersorwiththemaximumtake-offmassmorethan5700kgTCASFunctionTCASInformation根据入侵机的相对距离和方位，以及威胁等级在EHSI或EADI上显示视觉信息：Others（其它）：相对高度大于1200英尺、小于2700英尺，或距离在6海里以上。Proximity（接近）：相对高度等于或小于1200英尺，且距离在6海里以内。TrafficAdvisory（交通咨询）：系统判明的与本机存在潜在危险接近的飞机，TCASⅡ会提前一定时间（20~48秒）发出交通咨询。音频ResolutionAdvisory（决断咨询）：在对已判明为交通咨询的飞机连续监视约15秒后，如果该机与本机危险接近的状况仍然存在，则TCAS会发出解脱咨询。TCASInformationTCASInformationTCASInformationTCASInformationTCASInformationTCASInformationTCASInformation语音信息含义TRAFFIC,TRAFFIC交通，交通CLIMB,CLIMB爬升，爬升DESCEND,DESCEND下降，下降INCREASECLIMB…INCREASECLIMB增大爬升，增大爬升INCREASEDESCEND…INCREASEDESCEND增大下降，增大下降CLIMB,CROSSINGCLIMB…CLIMB,CROSSINGCLIMB爬升，穿越爬升…爬升，穿越爬升DESCEND,CROSSINGDESCEND…下降，穿越下降…CLIMB,CLIMBNOW…CLIMB,CLIMBNOW爬升，现在爬升…爬升，现在爬升DESCEND,DESCENDNOW…DESCEND,DESCENDNOW下降，现在下降…下降，现在下降ADJUSTVERTICALSPEED,ADJUST调节垂直速度，调节MORNITORVERTICALSPEED监视垂直速度MAINTAINVERTICALSPEED,MAINTAIN保持垂直速度，保持MAINTAINVERTICALSPEED…CROSSINGMAINTAIN保持垂直速度…保持穿越CLEAROFCONFLICT冲突解除TCASTESTTCAS自检TCASTESTOKTCAS自检通过TCASTESTFAILTCAS自检失败TCASInformationTCASAlertAreaTCASAlertAreaTCASPrincipleTCASPrincipleTCASPrincipleTCASPrincipleTCASPrincipleTCASPrincipleHorizontaltest:timetoreachtheClosestPointofApproach(CPA)(orDMODdistanceiftheclosurerateislow)Verticaltest:timetoreachco-altitude(orZTHRiftheaircraftaresteady)TheTA/RAthresholdvaluesincreasewiththealtitudeThebearingisnottakenintoaccount(onlyusedforthedisplay)TheTAorRAisissueddependingupontherelevantthresholdsRAsenseselection:objectiveofsafeverticaldistanceALIM,co-ordinationIftheintruderdoesnottransmititsaltitude,therewillbenoRATCASPrincipleILLUSTRATIONOFTHEHORIZONTALTESTIntruderTCASThecollisionavoidancecriterionisagenerallyatimeparameterTCASPrincipleLOWCLOSURERATEAirspeedClosurerateAirspeedIntruderTCASTheclosureratecanbeloweveniftheairspeedsarehigh.TCASPrincipleVERTICALTESTIntruderTCASThetimeremainingtoco-altitudeiscomparedtotriggeringtimethreshold(here35seconds)TCASIntruderZTHRZTHRIncaseofsteadyaircraft,currentverticaldistanceiscomparedtoverticalthresholdZTHR(e.g.800ft)TCASPrincipleALERTS:TRAFFICADVISORYThresholds:horizontal:20to48s(orDMOD=0.3to1.3NM)vertical:20to48s(orZTHR=850or1,200ft)Auralannunciation:Traffic,traffic”Intruder:solidambercircleHelpstothevisualacquisitionoftheintruderPreparesthecrewforapossibleRANomaneuvershouldbemadeifthereisnovisualacquisitionNoassociatedphraseologyTCASPrincipleALERTS:RESOLUTIONADVISORYThresholds:horizontal:15to35s(orDMOD=0.2to1.1NM)vertical:15to35s(orZTHR=600to800ft)Auralannunciations:climb,descend,increaseclimb,increasedescent,monitorverticalspeed,etcDisplayofarangeofverticalspeedsorpitchestoavoidObjective:asafeverticaldistanceALIMvaryingfrom300to700ftAnRAtakesintoaccountallexistingthreatsTheRAintensityischeckedandrevised,ifnecessary,everysecondTCASPrincipleTHRESHOLDVALUESFORTCASIIV7.0TARAFLou«Z»radiosondeSLTAU(s)DMOD(NM)ZTHR(ft)TAU(s)vtt*DMOD(NM)ZTHR(ft)ALIM(ft)FL4207481.3120035~251.1800700FL200~4207481.385035~251.1700600FL100~2006451.085030~220.8600400FL50~1005400.7585025~200.556003502350ft~FL504300.4885020~180.356003001000~2350ft3250.3385015~150.26003000~1000ft2200.3850NoRANoRANoRANoRA*vtt:verticalthresholdtest(processingof1,000-ftleveloffgeometries)TCASPrincipleRASENSESELECTIONThe'downward'sensewillachieveALIM,the'upward'sensewillnot.The'downward'optionisthereforeselectedTCASThreatCPA'downward''upward'ALIMALIMTCASPrincipleRAWITHOUTALTITUDECROSSINGBoth'downward'and'upward'senseswillachieveALIM.The'upward'senseisselectedbecauseitpreventstheTCASaircraftfromcrossingthroughtheintruder'saltitudeCPA‘Climb’RAissuedTCASThreatALIMALIMTCASPrincipleRAWITHALTITUDECROSSINGTheupwardsenseisnotsufficienttoachieveALIM.Thedownwardsense(Crossingdescenthere)RAischoosen,howeveritisreallyissuedonlywhenthecurrentverticalseparationislessthan600ft(intrudersteady)or850ft(intruderevolutingtowardtheownaircraft).Allthesecasesarerare.ALIMCPAALIMCrossingRAissuedTCASThreat600ftif1000ftlevel-off,thennoCrossingRATCASPrincipleINCREASERATERAThethreatincreaseitsdescentratetowardsTCASaircraftaftertheinitial“descent”RAisissued“descent”“Increasedescent”TCASThreatCPATCASPrincipleRAREVERSALTCASCPAThreatInitialRAReversalRAInitialprojectionTCASPrincipleMODECTARGETON-THE-GROUNDDETERMINATIONRadaraltimetervalue1,700feetabovegroundlevel(ThresholdbelowwhichTCASchecksfortargetsontheground)380-feetallowanceBarometricaltimeterGroundlevelStandardaltimetersettingEstimatedelevationofgroundDeclaredairborneTCASDeclaredongr