The Prototype Area Air Defense Commander Capability · Joint exercise experience of staff officerswho have used the prototype at APL and at sea. Planning Module The planning module

138 JOHNSHOPKINSAPLTECHNICALDIGEST,VOLUME23,NUMBERS2and3(2002)

J. H. PROSSER et al.

T

ThePrototypeAreaAirDefenseCommanderCapability

Joseph H. Prosser, Michael T. Dennehy, Roger A. Sumey, and Edward P. Lee

he Area Air Defense Commander (AADC) of a theater of operations has theresponsibilityofallocatingandcoordinatingairdefenseassetstomaximizetheireffective-nessincounteringenemyairandballisticmissileattacks.Airdefensemustbeplannedandexecuted inenvironmentswhereincriticaldataelementsandbattleconditionschangefrequentlyandunexpectedly.Aspartofacontinuingefforttogivethecommandertheabilitytogenerateplansandexecutetheminsuchenvironments,APLhasbuiltapro-totypecapabilityconsistingofasetofintegratedinformationmanagement,analysis,col-laboration,anddisplaytools.ThesetoolsenabletheAADC,forthefirsttime,todevelopandexecute timelyairdefenseplans thatoptimize theatercombatpower inadynamicenvironment.

INTRODUCTIONThe mission of the Area Air Defense Commander

(AADC) is toprotectdefendedassets (DAs) thatarevitaltotheateroperationsagainstmissilesandaircraft.DAstypicallyincludeairports,seaports,criticalgovern-ment installations, and concentrated civilian popula-tions. These assets are selected, often in consultationwithhigherauthority,bytheCommanderoftheJointTaskForce(CJTF)andareassignedto theAADCtodefendinagivenpriorityorder.TheresultantproductisaDefendedAssetList(DAL).

AlthoughtheAADCisassignedairdefenseweaponstoprotectDAs,thereisalwaysashortageofweapons,leavingmoreDAsthanweaponsavailablefordefense.A capability was needed to develop plans that wouldprovideefficient,effective,synergisticairdefensesolu-tionsinanenvironmentthreatenedbyTheaterBallisticMissiles(TBMs),aircraft,andotheroffensiveweapons,someofwhichcouldbeweaponsofmassdestruction.

IndevelopingtheTheaterAirDefense(TAD)solu-tion, the air defense planner must digest a myriad ofinformation pertaining to enemy weapons and theiremployment, friendlyweaponsandtheiremployment,thephysicalareaofeachDA,andthepriorityofeachDAforairdefense.LaboriouslybuildingaTADplan,whichcantakehoursordays,willnotsufficeintoday’sdynamic, frequently changing environment. The newcapabilitymustproduce,inminutes,solutionsforvari-ouscontingenciesandphasesofthecampaign.Duringattack, this capability must also provide a real-timecapability toaudit thebattlespacebyassessingperfor-manceof theairbattleandassigning friendlyweaponengagementswhereshortagesexist.

The Navy’s requirement to initiate first-on-scene,integratedTADhasledtothedevelopmentofaproto-typeAADCcapabilityforevaluationinanAegiscruiserandacommandship.Thiscapabilitywasdevelopedat

JOHNSHOPKINSAPLTECHNICALDIGEST,VOLUME23,NUMBERS2and3(2002) 139

PROTOTYPE AADC CAPABILITY

thedirectionoftheAssistantChiefofNavalOperationsforSurfaceWarfare(N86)andtheProgramExecutiveOfficeforTheaterSurfaceCombatants(PEO(TSC)).Itsprincipalgoalsareto

• Verify and refine requirements of the OperationalRequirementsDocument

• Defineengineeringrequirementsforproduction• Developcommontactics,techniques,andprocedures

inairdefenseandairspacemanagement• Developnewstandardsreflectingadvancedtechnology• HelpinthedevelopmentofJointservicesarchitecture• Helpindefininghardwareandsoftwarerequirements

forcollaborativeplanning

THE PROTOTYPE AADC CAPABILITYTheprototypeAADCcapabilityoptimizesairdefense

weaponssystemperformanceattheoperationallevelofwar.Whenappropriate,italsosupportstrade-offanaly-sisatthetacticallevelofwar.Theprototypeprovidestwocapabilities:

1. Continuous, dynamic, synchronized, collaborative,wargamed,predictiveTADplanninginanenviron-mentwherecriticaldataelementschangefrequently.The normal operational environment for the pro-totype AADC capability requires the capacity tosimultaneouslyworkvariantstoplans,developmul-tiplecoursesofaction(COAs)for follow-onplans,develop long-rangeplans forallphasesof thecam-paign, support component commander requests forinformation, andprovide responses to theCJTF insupport of optimizing the allocation of air defenseassetsthroughoutthetheater.TheAADCcanpro-duce TAD stationing plans within minutes, insidetheenemy’sdecisioncycle.Thisrapidplanningcapa-bilityisneededtogenerateproductsthatenablecol-laboration of prospective plans with supporting airdefense units, component commanders, and otherorganizationsneededtoexecuteanairdefenseplan.

2. Continuous,reliablevisualizationofthebattlespaceforunambiguoussituationalunderstandingtoenabletheAADCtoauditthebattlespaceandexecutereal-time command and control as necessary. The real-time battlespace “picture” is fully comprehensibleby all levels involved in decision making. This isaccomplishedbyvisualizing theoperationalpictureinthreedimensions,overlaidwithanarrayofon-callvisualaids(e.g.,airspacecoordinationorder,ballisticmissileflightprojections,surveillancecontours)andsupportedbydecisionaidsthathelpoptimizeengage-mentoftheenemy.

These twocapabilities areprovidedwithin theproto-typeintwoseparatemannedspaces:aplanningmoduleandacurrentoperationsmodule.

THEATER AIR DEFENSE PLANNINGTheairdefenseplanningprocessinvolvestheplace-

mentandcoordinationoffriendlyairdefenseassetsinatheaterofoperationsfordefenseagainstballisticmissileandairattacks.TheprototypeAADCcapabilityisasetoftoolsusedbyairdefenseplannersthatenables,inmin-utes, the development of multiple, feasible air defenseplans in response to a rapidly changingplanningenvi-ronment.Toolsforplangeneration,collaboration,eval-uation,andanalysisareembeddedwithintheprototype.Withthiscapability,theAADCstaffcanmakeinformeddecisionsconcerningtheallocationofassets.

Manning TheprototypeAADCplanningmodulesupportsan

airdefenseplanningteamconsistingof13AADCstaffofficers: 5 planners; a head planner; a 3-person intel-ligence team; land, maritime, and air liaison officers;and an information manager. The head planner usesthe guidance of the commander to task the plannersindevelopingandevaluatingCOAalternatives.Whiletheplannersarecontinuouslydevelopingthesealterna-tives, the intelligence teamgathers informationaboutthe locationand likely intentionsof theenemy.NewintelligenceestimatesareusedbytheplanningteamtodevelopCOAalternativesresponsivetothenewthreat.Information comes into the prototype via e-mailand voice, and through active collaboration of theliaison officers with the land, maritime, and aircomponentcommanders.Thishighvolumeofinforma-tion is sortedandprioritizedby the informationman-ager, who ensures that data relevant to the AADCmission are communicated to the head planner. Thisparticular manning configuration is the result of theJointexerciseexperienceofstaffofficerswhohaveusedtheprototypeatAPLandatsea.

Planning ModuleThe planning module (Fig. 1) consists of a central

conferencetablesurroundedbyfivemultipurposeplan-ning consoles, a video-teleconferencing system, and alarge-screen display. The head planner station at theheadoftheconferencetablehasapop-upLCDdisplayandapull-outkeyboardtomonitorandevaluateplandevelopmentbythestaff.Theheadplannerhascontrolofthelarge-screendisplay,whichcanbeusedtoshowtheplanningconsoledisplays.

Eachplanningconsoleisequippedwitha24-in.mon-itor,keyboard,mouse/trackball,STU-IIIsecurephone,headsetwithmicrophone,andsecureradio.Akeyboard/video/mouse switch gives each console operator fullyfunctional access to Silicon Graphics (SGI) worksta-tionsforplanning,andgeneral-purposeembeddedPCsfor other related tasks. This flexible equipment suiteis necessary to give planners fast and easy access to



communicationswithland,maritime,andaircomponentcommanders,aswellasintelligencesources,tomaintaincurrentawarenessoftheoperationalenvironment.

Planning EnvironmentThe data elements needed to properly execute air

defenseplanning reside in aplandatabase thatdefinestheDAs,friendlyairdefenseassets,andthelikelyposi-tionsandintentionsoftheenemy.TheDALisapriori-tizedlistofDAswithspecifiedlevelsofprotection.Thelist,asnotedpreviously,comestotheplanningmodulefromtheCJTFandconsistsofunits,cities,orgeographicareas(e.g.,air/seaports,government installations) thatmustbedefendedagainstballisticmissileandairattacks.

Theenemyorderofbattle(EOB)isasetofthreatswithassociatedgeographicuncertaintyareascharacter-izingthetypesofweaponsavailabletotheenemyandthelikelynumbersandlocationsofthoseweapons.Inadditiontoneedingthenumbersandlocationsofenemyweapons, planners have to know the capabilities andintentionsoftheenemytodeliverthoseweapons.Thisisanenemycourseofaction(ECOA),anditincludesraid-sizelimitscharacterizingthemagnitudeofattackslikelyfromeachenemythreattoeachDA.

To counter the enemy threat, the CJTF allocatesdefensive units to the AADC, which are entered asthe friendly order of battle (FOB). The FOB includesAegisshipswithAreaAirWarfare(AAW),NavyAreaDefense(NAD)orNavyTheaterWide(NTW)capabil-ities;PatriotorHawkbattalions;TheaterHighAltitudeAirDefense(THAAD)batteries;andvariousaircraft.

The COAs developed by the AADC staff mustrepresent the current operational reality of the bat-tlefield, where data elements can change frequently

Figure 1. The prototype AADC planning module.

andunexpectedly.TheDALcancomeintotheproto-typeasaformattedtextmessagewhichcanbeparsedautomatically, or via e-mail, voice, or any of thebuilt-incollaborationtools.EOBandECOAinforma-tionisgatheredbytheAADCstaffthroughitsthree-person intelligence cell via collaboration and elec-tronic requests for information. FOB weapons loadsandstatusareobtainedthroughcollaborationwiththeland,maritime,andaircomponentcommanders.

Thebreakthroughof theprototypeAADCcapabil-ity is the ability to assess the possible effects of newinformationinminutesasopposedtohoursordays.Forexample,DAsmaybeaddedorremoved,DAprioritiesmay change, or level-of-protection requirements mayvary.NewintelligenceestimatesbasedonbattledamageassessmentsorreportsonenemylocationsmayaffecttheEOB.TheECOAmaychangewhenthebattleescalatesorwhenitissuspectedthatweaponsofmassdestructionwillbeused.Whenacriticaldataelementchanges,theprototypeallowstheAADCtorespondquicklyandtoreallocateresourcesasappropriate.

Plan GenerationOnceplanningdatahavebeenacquired,planscanbe

generatedautomatically.Theautomaticplanner readsinDAL,EOB,ECOA,andFOBdataandproducessta-tioningassignmentsofFOBassetstoDAsandthreats,optimizingtheatercombatpower.DAsarecoveredbytheautomaticplannerinpriorityordertotherequiredraidsizeandprobabilityofkill(Pk)specifications,whilemaking maximum use of friendly assets without over-covering any DAs or threats. The automatic plannerevaluates thousands of unit placement possibilities inparallel,solvingthetheater-wideoptimizationproblem



within minutes. Plan alternatives can be generatedsimultaneously from multiple workstations to accountfor multiple contingencies or varying theater condi-tions.Thelargenumberofplansgeneratedcanbeeval-uated and compared simultaneously through collabo-rationamongRegionalAirDefenseCommanders,theCJTF,andotherstoproducethesinglemostsynergisticairdefenseplanpossibleinashortperiodoftime.Therapid generation of air defense stations for a complexJoint operations area (JOA) is facilitated by a Cray-linked24-processorSGIOrigin2000server.Thisauto-matic planning tool uses parallel algorithms for assetallocation, coverage evaluation, and unit stationingagainst short- and medium-range TBM threats, air-breathingthreats(ABT),andAnti-ShipCruiseMissile(ASCM)threats.

Adistinguishingfeatureoftheprototypeautomaticplanner is its ability to generate areas of maneuver(AOMs)surroundingtheoptimalpositionsof friendlyassets. An AOM for a unit is the set of stationinglocationswheretheunitcanachievethedesiredlevelofprotectiononitsassignedthreatsandDAs.Therespon-sibilityforhandlingthetacticaldetailsofstationingtheunitislefttothosewhoknowthemostaboutit—thecommandersinthefield.TheAOMsarealsoassessed,inadvance,throughcollaborationwiththesupportingcommanders to validate stationing options and givemovement-orderwarnings.Thiscapabilityiskeytopro-ducingafeasibleplanthatwillbeacceptedbyboththeAADCsupportingcommandersandtheCJTF.

The prototype AADC capability uses high-fidelitymodelsofairdefense sensors,weapons,andthreats toprovide the performance information needed to gen-erate andevaluate friendly asset stations.Because theAADCfunctionsattheoperationallevelofwar—syn-chronizingfriendlyforcesthroughoutthetheateracrossall phases of the Joint campaign—these models wereproduced toaccount for theeffectsof systemconfigu-rationandoperatingenvironment inproviding realis-tic predictions of air defense system performance. Forexample,terrainblockageforradarsatallpotentialsta-tion locations is computedusing elevationdatabasedonDigitalTerrainElevationDataLevel1producedbytheNationalImageryandMappingAgency(NIMA).

The models in the prototype must provide perfor-manceresultswithinfractionsofasecondtofacilitatethequickgenerationofairdefenseplans.Consequently,friendlyweaponsperformancemodels,suchasthelargeand complex six-degree-of-freedom (6-DOF) modelsdevelopedattheLaboratoryforStandardMissilevari-ants, have been run offline to generate time-of-flightand probability-of-kill tables for the full battlespaceof each weapon against the short- and medium-rangeTBM,ASCM,andABTthreatscontainedintheproto-type.Datafromthesetablesareintegratedwithonlineoutputfromsensorandweaponcontrolsystemmodels

toproduceengagementperformancepredictionsagainstanyofthefullsetofairdefensethreats.

StationingunitscapableofengagingTBMthreatsintheuppertier(i.e.,AegisNTWandTHAADunits)andlowertier(i.e.,AegisNADandPatriotunits),orunitscapable of engaging ABT threats (i.e., Aegis AAW,Patriot, and Hawk units) involves a combination of alocalized and theater-wide evaluation of thousands ofpotentiallocationsintheJOA.Thissearchisperformedusing the high-fidelity models of friendly and enemyweapons systems along with terrain data. It requiresthe computation of hundreds of weapons performancecontours, several foreachpotentialunit location.Setsofsuchlocationsthatachievesimilarcoverageareinter-sected to form hundreds of candidate AOMs for eachunitintheplan.Mathematicalprogrammingtechniques1areusedtochoosethebestAOMforeachunit.

The planning techniques are formalized in amathematical framework that accounts for the manydifferent threat and unit types handled by the proto-type.Thenumbersofdifferentelementsinanyplanaredefinedasfollows:P=numberofairdefenseunits,M=numberofDAs,andR=numberofthreatareas.

Theseelementsarereferencedbyindex.Forexample,theplancontainsunit1throughunitP,DA1throughDAM,andthreat1throughthreatR.Instancesoftheseitemsarereferencedasunitp,DAm,andthreatr,whereitisassumedthatprangesfrom1toP,mrangesfrom1toM,andrrangesfrom1toR.TheenemyattacksDAm from threat area r with a raid of magnitude tmr. Ofcourse, tmr ≥ 0, and ifDAm isoutside thegeographicareathatcanbereachedbythreatr,thentmr =0.

TheenemyhasalimitedcapacitytosimultaneouslyattackeitherasingleDAormultipleDAsfromeitherasinglethreatareaormultiplethreatareas.Theselimitsaredefinedbythefollowinginequalities:

foreverymandr,tmr≤Emr, (1)

foreverym, t Dmr mr

≤∑ , and (2)

foreveryr, t Tmr rm

≤∑ . (3)

The numbers Emr, Dm, and Tr (for every m and r)come from intelligence data as part of the ECOA.Inequality1representsraid-sizelimitsonthreatsgoingfromindividualthreatareastoindividualDAs.Inequal-ity2representsraid-sizelimitsonthetotalnumberofthreats going simultaneously from all threat areas tothe same DA. Inequality 3 represents raid-size limitsonthetotalnumberof threatscomingsimultaneouslyfrom the same threat area and going to all DAs. An



admissible attackisasetofm ×r numbers{tmr}thatsatisfyinequities 1–3, representing a simultaneous attack ofone or more DAs from one or more threat areas,withinallspecifiedenemyraid-sizelimits.Animpor-tantfeatureofthisthreatcharacterizationisthatitdoesnotspecifythepreciseattackplanoftheenemy,butratherasetofpossibleECOAs.Thisgivesairdefenseplannerstheflexibilitynecessarytodefinethreatsce-narioswhen theenemy’s attackplan isnotpreciselyknown.

The automatic planner computes candidate AOMsfor everyunit in theplanbyevaluating friendlyweap-onsperformanceintheJOA.ThenumberofcandidateAOMsfoundforunitpisdenotedNp.ThecompletesetofcandidateAOMs(involvingallunits)ischaracterizedbyabinary-valuedfunctiona(m,r,p, j),where jrangesfrom1throughNp.Weseta(m,r,p,j)=1ifunitpbeinginsideAOMjimpliesthatitwouldbeabletoengage(atthe required probability of kill) the threat tmr. In thiscase,wecanexpectthatifthecorrespondingAOMischosen for theunit and tmr>0, that is, if the enemyattacks DA m with threats from threat r, then unit pwould be able to engage those threats. If the unit isunabletoengagesuchthreatswhenitisinsideAOMj,thena(m,r,p,j)=0.

Of course, more than one threat or DA may beinvolvedinanattack,andmorethanoneunitmaybeinvolvedinthedefenseagainsttheattack.UnitAOMsare therefore selected so that they complement eachother,ensuringthatthreatsarenotovercoveredattheexpenseofleavingotherareasuncovered.Tothisend,wedefineanotherbinary-valuedfunctionx(p,j),whichisanAOM selecting function.Wesetx(p, j)=1 if thecandidateAOMjofunitpisselectedfortheplan,andx(p,j)=0otherwise.OnlyoneAOMcanbeselectedforeachunit,requiringforallp,

x p, jj

( ) .≤∑ 1 (4)

The planning problem is to determine the functionx(p, j)(i.e., toselectAOMs)tocoverthethreatsandDAsintheplan.

Foragivenattacktobeconsideredcovered,unitcapa-bilitiesmustbeassignedtotheincomingthreatsinsuchawaythateverythreatisengagedtotherequiredprob-abilityofkill.Unitcapabilitiesareexpressedintermsofaraid-sizehandlingcapacityUp.ThevalueofUp dependsontheunit’sabilitytosustainsimultaneousengagementsandontheweaponsloadoftheunit(whichcomesfromtheFOB).Lett = {tmr}beanyadmissibleattack.Letst(p, m, r)beaninteger-valuedassignment functionthatspeci-fiesfortheattackthowmanyengagementsunitpassignstotmr. Fortheattackttobecoveredbyaparticularselec-tionofmaneuverareas,thisassignmentfunctionstmustsatisfythefollowingproperties:

forallp, s p, m, r x p, j a m, r, p, j Ut pj, m, r

( ) ( ) ( ) ,⋅ ⋅ ≤∑ and (5)

forallmand r, s p, m, r x p, j a m, r, p, j tt mrp, j

( ) ( ) ( ) .⋅ ⋅ ≥∑ (6)

Thetermx(p,j)⋅a(m,r,p,j)isequalto1ifandonlyifAOMjofunitpisselectedandtheunitcanengagethe threat tmr while inside AOM j. The first of thesetwopropertiesistherequirementthatthetotalnumberofengagementsassigned to threatsbyunitpdoesnotexceed the unit’s capability to simultaneously engagethosethreats.Thesecondofthesetwopropertiesistherequirementthattherebeasufficientnumberofengage-mentsassignedsothateverythreatisengaged.

Foraspecificattackt,thedeterminationoftheexis-tenceofanassignment functionst thatsatisfiesEqs.5and 6 is equivalent to checking for the existence ofa solution to a certain linear programming problem.Ofcourse,inorderfortheDAsinaplantobeconsid-eredcovered,everyadmissibleattackmustbecovered.Toaccomplishthis,thecoverageevaluationmoduleoftheautomaticplannerrunshundredsoflinearprogramsthat estimate worst-case attack situations, comparingtheresultstothecapabilitiesofunitsstationedtocoun-tereachattackaccordingtoEqs.5and6.

Additional factors that extend the model statedaboveareasfollows:

• DAsmustbecoveredinpriorityorder.• TheraidsizesagainstclustersofDAscanbelimited.• A higher probability of kill can be achieved by

assigningmultipleengagementstothesametarget.• SomeunitscansimultaneouslyengageTBMsinthe

uppertier,TBMsinthelowertier,andABTs.• PartialareacoverageofaDAispossible.• Partialcoverageofthreatareasispossible.• Probabilitiesofkillcanbepartiallyachieved.

Furthermore, the automatic planner characterizes(foreveryconsideredsetofselectedAOMs)thesetofadmissible attacks that are not covered. This infor-mationisusedinasequentialalgorithmthatmakesthefinaldeterminationoftheselectedAOMsintheplan.OncetheAOMshavebeenfinalized,automatedanaly-sisprovidesacoveragesummarythatcanbedisplayedontheplanningworkstation.Thesesummarydataaccountfor the complete set of ECOA possibilities as definedin theEOBandECOA,and they show the locationsofareasofnocoverageandareasofpartialcoverage.Aquantitativeanalysisoftheriskassociatedwithaplancanthenbeproducedwiththewargamingtoolsembed-dedintheprototypeAADCcapability.

WargamingThewargaming toolsprovideMonteCarlo evalua-

tionsofaplan.Theriskassociatedwithaplanisbased



on the number of threats that are expected to leakthroughfriendlydefenses(i.e.,leakers).Leakerstatisticsareacquiredviaasetofrandomlygeneratedthreatsce-nariosselectedfromalladmissibleattacks.Threatsarelaunchedfromrandomlyselectedlaunchpointswithintheirdefinedthreatareasandareflownalongsimulatedtrajectoriestorandomlyselectedimpactpointswithinthe defended areas under attack. An optimum force-on-force engagement schedule that best achieves therequired probability of kill against all threats simulta-neously—all within the capabilities of friendly radar,launcher,illuminator,andmissilesystems—iscontinu-ouslygeneratedandexecutedthroughoutthesimulatedattacks. Defensive surface-to-air missiles (SAMs) arelaunched in accordance with the engagement sched-ules. When a threat intercept occurs, a kill or a misseventisrandomlygeneratedaccordingtotheprobabil-ityofkillassociatedwiththelocationandkinematicsoftheintercept.

The number of threats expected to leak throughfriendly air defenses is the primary wargaming result.ForeachDA,statisticsonthenumberofthreatsflown,the number of SAMs fired, and the number of ABT,ASCM, and TBM leakers are indicated along withthe reason foreach leaker.Athreatcan leak throughwithouteverbeingengagedifitimpactsanuncoveredportionofaDA,orifitispartofamassraidthatover-whelmstheengagementcapacityoffriendlyairdefenses.A threatcanalso leak throughbecause it isunderen-gaged, i.e., the raid sizes are large enough to preventsufficientmissiles frombeing launched toachieve therequiredprobabilityofkill.Of course, a fully engagedthreatcanalsoleakthroughsinceprobabilityofkillisnever 100%. This comprehensive leaker characteriza-tionisusedbythedecisionmakertoevaluatetheriskassociatedwithaplan.

Theprototypeprovidesgraphicaltoolsforcomparingleakerstatisticsfrommultipleplans.Anexampleofthiscomparison appears in Fig. 2. This visualization givesthedecisionmakertheabilitytorapidlyunderstanddif-ferencesamongplans.

CollaborationAcrucialelementoftheplangenerationprocess is

continuous collaboration among the AADC plannersand component commander planning staffs to ensurethe feasibility of friendly unit mission and stationingoptions.Collaborationalsolinksairdefenseplannersinthetheater,thusensuringthatallcommandsinvolvedintheexecutionofaplanarealsoinvolvedinthedevel-opmentofthatplan.

Collaborationtoolsembeddedintheprototypepro-vide textual, graphical, and voice communicationsamong planners and external sites over the SecretInternetProtocolRouterNetwork (SIPRNET)usingthe COMPASS (Common Operational, Modeling,

Planning,andSimulationStrategy)collaborationcapa-bility.Anonlinechatcapabilityiscoupledtoagraphi-cal“whiteboard”thatfacilitatesinteractivescreenimagetransfer and annotation for planners at remote loca-tions. The prototype can also export geographicallyreferencedplan items(e.g., threatareas,weaponsper-formance contours, and AOMs) to an external site,wheretheyarecorrectlylocatedanddrawnonthemap-ping system. SIPRNET voice is used with these toolsto provide robust communications to computer usersat external sites. An embedded Web browser is usedtoaccessSIPRNETWebsitesforinformationrelevanttoAADCoperations.TheprototypeAADCcapabilityalso maintains a Web site where planners can maketheirdocumentsaccessibletootheractivities.

AADC CURRENT OPERATIONSAADCcurrentoperationsinvolvearound-the-clock

audit of the theater battlespace. Potential threats areconstantly evaluated, and the performance of theaterforcesinprotectingDAsisconstantlyassessed.Duringan air battle, weapon engagements may be assignedwhere shortages exist and duplicate or unnecessaryengagement assignments may be negated. To supportthis, a continuous, reliable visualization of the bat-tlespaceispresented,drivenbyanintegrated,real-timedatabaseofradarcontactsortracksfromallcontribut-ing sensors in theater. Ideally, each actual aircraft intheaterwillberepresentedbyoneandonlyonetrackinthedatabase.Additionally,eachwillbecontinuouslyevaluatedforidentificationofintent(friendly,hostile,commercial,orunknown).TheprototypeAADCcur-rentoperationsmodulecanaccepttheseintegratedbat-tlespacedatafromanumberofdatalinkstoproducethebattlespacepicture.Severaldecisionaidsarealsoavail-able to support threat evaluation, performance assess-ment,andengagementactivities.

Current Operations Module Manning Thecurrentoperationsmoduleisconfiguredtosup-

portfiveofficers: threewatch-standers, abattle-watch

Defended assets1 2 3 4 5 6 7 8

0.5

1.0

1.5

2.0

Ave

rage

leak

ers

0

Test 6Test 5Test 4

Figure 2. Wargame result comparison graph generated by the prototype AADC capability. Each of the three test plans being compared has eight DAs. The expected total number of leakers (TBM, ABT, and ASCM) is shown for each DA, with an associated confidence interval. (Average leakers per DA, ±1 .)



captain, and the AADC. Experience in the field hasconfirmed that this is sufficientmanpower tomonitorandcontrolatheater-widebattlespace,givenacapabil-ity such as the prototype AADC to provide a single,integrated battlespace picture that is comprehensiblebyalldecisionmakers.Thoughtaskingresponsibilitiesare determined by the commander in the field, it isenvisionedthattwowatch-standerswillbeassignedasliaisons to Regional Air Defense Commanders in thetheater while the third watch-stander will serve astheJointInterfaceControlOfficer(JICO).TheJICOensures that high-quality track data are entering thesystemthroughmanagementofthedatalinksandtheircontributors. The battle-watch captain and AADCmaintain situational awareness over all regions in thetheater andexecutedecentralized commandandcon-trolasnecessary.

Theofficersaresupportedbythreeconsoles,atwo-seatedelevatedbattle-watchcommanddais,anHDTVprojectorthatproducesalarge84.5ftdepictionofthereal-timebattlespace,alargebannerboardforsurfacingalerts, two smaller banner boards to indicate currentweaponsstatusoftheregions,andstatusmonitorsthatdisplayfriendlyunitreadinessanddatalinkinputqual-ity.Figure3showsatypicaloperationsmodulelayout.

Each console of the prototype current operationsmoduleisdrivenbyatwo-processorSGIOnyx2work-station,andallaresupportedbySGIOrigin2000serv-ers for decision-aid processing. Consoles are equippedwith a 28-in. HDTV monitor for display of the three-dimensional(3-D)real-timebattlespacepicture,avari-ableactionbuttonarrayforfrequentorcriticalactions,atrackball,aspaceball(a6-DOFinputdevice)for3-Dview control, a microphone for speech recognition, a

14-in.LCDdisplayfordetailedactionsandofficeappli-cations,asecuretelephoneunit,andasecureradioset.Thebattle-watchcommandstationissimilarlyequipped,except it uses the HDTV projector instead of a 28-in.monitor.TheHDTVprojectorisequippedwithavideoswitchthatallowsthebattle-watchcaptaintoshowanyofthefourstations’3-Ddisplaysonthelargescreen.

Display of the TAD Picture The main component of the current operations

module is the display of the battlespace. This displayprovidesunambiguoussituationalunderstandingtodeci-sionmakersatalllevels,enablingthemtomonitorandcontrolthebattlespaceasnecessary.Frominformationpresentedonthedisplay,acommandercanidentifyandevaluatepotentialthreatsandthefriendlyforce’sabilitytocounterthem.2

TheprototypeAADCbattlespacedisplayoffers aninteractive3-Dperspectiveofsensordataoverlaidwithan array of on-call AAW visual aids. The repre-sentation closely resembles the external reality of air-craft, surface ships, and land-based units operatingaround the land masses of a theater, modified froma realistic rendering as needed to promote rapidcomprehension of tactically relevant information(Fig. 4). With a spaceball, the user can navigate bydirectly manipulating the view to examine the repre-sentation fromanypositionabovetheEarth’s surface.As theuser’sviewchanges, the representationrapidlyupdates or animates, enhancing the sense of realism,control,andcomprehensionof spatial relationships inthebattlespace.

Insteadofusingatraditionalflatmapprojection,theprototypeAADCdisplay shows theEarthas a sphere

Figure 3. The prototype AADC current operations module.



withoceansandlandmasses.Thelandmassesincludegraphical depictions of detailed coastlines, nationalboundaries,lakes,rivers,cities,commercialairways,andelevation terrain derived from the NIMA. Terrain isrenderedasmountainsandvalleyson theEarth’s sur-face.Airways(updatedmonthly)arepresentedastrans-parent strips overlaid on the Earth’s surface and areinvaluableinjudgingwhetheranaircontactisacom-mercialairliner.

The prototype AADC current operations displayshows air, maritime (or surface), and land contactsdetected by force units using realistic 3-D icons thatreflect the position and heading of the contacts in3-D space. The contacts or tracks can originate fromorganic real-time sensors, satellite-based infrared sen-sorsfromtheDefenseSupportProgram(DSP),andsen-sors detecting electronic intelligence (ELINT) emis-sions. Real-time tracks are shown as solid objects toemphasize that their positions are basedonharddatathat are constantly updated. DSP and ELINT tracksareshownastransparentorghostlyobjectstoempha-sizethattheirpositionsareestimatedorbasedondatedinformation.Theshapeandcolorofeachsymboldenotetactical identification such as airliners, fighters, andtankers.Theshapeoffriendlyaircraft(e.g.,whetheratrack is shown as an F-14 or an F-16) is further dis-tinguishedbyautomaticallycorrelatingreal-timetrackinformation with missions in the air tasking order(ATO).TheATOisproducedbytheJointForcesAirComponent Commander and indicates when particu-lar types of aircraft will be flying and what interroga-tion, friend or foe (IFF) codes they will respond withwheninterrogated.Tracksymbolsarealsodrawnwithapitchtoindicatewhetheranaircontactisascending,descending,orflyingatasteadyaltitude.Eachsymbolhas a corresponding shadow drawn with the appro-priate shape and orientation. Rather than showingwhereashadowfromtheSunwouldfall,however,the

shadow’s placement indicates thetrack’s “ground truth,” that is, thepositionontheEarth’ssurfaceoverwhich the track is flying.Thedis-tance between the shadow andthetracksupportscoarsejudgmentsandcomparisonsoftrackaltitudes.Protruding from each shadow isa vector, called a velocity leader,whichisaroughindicatorofspeed.

AAW visual aids that can beoverlaid onto this picture by theprototypeAADCcapabilityincludeairspacecoordinationorder(ACO)areas, ballistic missile fly-out pro-jections, ongoing engagements ofthreats, and the current defensivecounter air plan. ACO areas are

Figure 4. The prototype AADC capability’s 3-D perspective display of the TAD picture.

specificationsfortheuseofairspaceforsuchfactorsascombatairpatrolstations,carrierbattlegroupoperatingareas,andminimumriskroutesthatarereceivedtextu-allyinstandardmilitarymessagetraffic.ACOmessagesareautomaticallyparsedandtheareasaredepictedonthedisplayastransparentvolumesin3-Dspace.TBMsare rendered as air tracks with the addition of esti-matedlaunchandimpactpointsalongwithflightpaths.All ongoing engagements of threats by friendly unitsreported on the data links are displayed as pairinglinesbetweenthethreatandtheshooter.Theexpectedthreats, theDAL,and theunit lay-downsandAOMsfromthecurrentdefensivecounterairplancanallbeoverlaid on the current track picture. The results ofdecisionaidsforthreatevaluation,weaponsassignment,performanceassessment,andrapidreplanningcanalsobeoverlaidgraphically.

Thehigh-levelsystemarchitectureoftheprototypeAADC graphics display software supports the high-speed rendering of all these data. A multiprocessingcomputersystemisusedandthesoftwareelementsarepartitioned to allow simultaneous rendering, displayobject generation, and event handling. To maximizegraphicsthroughput,idletimeandprocessingtimehavebeeneliminatedorreducedintherenderingprocess.Bydividing display object generation among several pro-cessorsandpartitioningtheresultingobjects, theren-derercanbegindrawingdataasobjectsbecomereadyinsteadofwaitinguntilallareavailable.Throughtheuseofsharedmemory,communicationspathsfromthedatagenerationprocesses and the rendererhavebeenremoved, eliminating message interrupts and process-ingwithintherenderer.Externaleventhandling(e.g.,spaceballactions)hasbeenrelegatedtoanotherprocess,furtherstreamliningtherenderer.TheprototypeAADCdisplaygenerationdesignalsosupportsfine-grainedpre-emptionofdrawingstoensureadequateresponsetothedecisionmaker.Fine-grainedpreemption lets theuser



interrupt the system while a scene is being drawn toallowimmediateresponsetonewcommands.

Threat Evaluation and Weapons AssignmentInadditiontothedisplayofthetheaterairpicture,

the prototype also provides three decision aids forthreatevaluation:threatranking,alertconditions,anddeephistory.Atheaterairpicturemayconsistofhun-dreds of air contacts. Successful threat evaluation islargelydeterminedbyknowingwhattoexaminefirst.To cue the decision maker, the current operationsmodule’sthreat-rankingdecisionaidperiodicallyeval-uates every real-time track. Every 4 s it develops arank ordering of the top 20 tracks exhibiting thegreatest likelihoodforhostile intent.Whendevelop-ingtherankorder,thethreat-rankingalgorithmevalu-ates track heading, speed versus range, closest pointofapproach,andspeedversusaltitudewithrespecttothe DAs in the current active defensive counter airplan. Decision makers can bias this ranking by indi-catingthattheywanttrackslocatedinspecifiedgeo-graphicentities(e.g.,aknownchemicalweaponssite)toappearhigherorlowerintherankorder.

Anotherdecisionaidtocuethedecisionmakeristheuser specificationofalertconditions.Each setofalertconditionsdelineates criteria that a trackmust satisfyforthegenerationofanalertmessage.Trackcharacter-isticsthatcanbeevaluatedforalerts includeidentity,category, geographic location (e.g., an airway), range,closestpointofapproach,speed,altitude,attitude,andheading. Alert conditions can be used to detect bothhostilesituationsandunwantedfriendlyactionssuchastheviolationofairspacerestrictions.

A largepartof threatevaluation isknowingwhereanaircontactoriginatedandwhatithasdone.Adeephistorycapabilitywithintheprototype integratesdatafrom unit sensors, the local combat system, and datalinksfora1-hcompositetrackhistoryforeverytrack.Eachtrack’shistoryindicateswhereandwhenalltacti-callysignificanteventshaveoccurred.Historydataaredisplayedas3-Dflightprofilestrailinguser-selectedor“hooked”tracksonthe3-Dbattlespacepicture.Historytrailsconsistofaseriesofdots,oneforeachtrackupdatereceivedonadatalink.Eachdotiscoloredaccordingtothetrackidentityatthetimeoftheupdate.Whenatrackisdroppedandthenreacquired,thedeephistoryaidisabletocorrelatethedroppedtrackwiththenewtrack.Theoldhistory trail is combinedwith thenewtrailtoformonecontinuoustrail.Gapsintrailscausedby gaps in radar detection data are filled in with 3-Dsplines of estimated flight paths. Trails may be anno-tatedonthedisplaywithboxesofamplifyingdata forcertaineventssuchaswhichunitisresponsibleforanidentityortracknumberchange.

If,followingathoroughthreatevaluation,adecisionmakerdeemsanactionnecessary,thecurrentoperations

moduleprovidesatrialengagementtooltoaidinweap-onsassignment.Theweaponsassignmentcapabilitypro-vides for theater-wide engagement planning of user-selectedthreatsusingaprobability-of-interceptlevelingalgorithm.Thealgorithm surveys all available shootersintheaterandcomputesatrialtheater-levelengagementstrategythatassuresatleastaminimumcumulativeprob-abilityofinterceptagainstalluser-selectedthreatscon-currently, subject to time and equipment constraints.Theminimumcumulativeprobabilityisdictatedbythedecision maker in the defensive counter air plan. Theprobabilitiesof interceptofanengagementstrategyarecalculated from models of weapon performance. Theresultsofthecomputationareintegratedgraphicallyintothe3-Dbattlespacepictureandareupdatedeverysecond.Theweaponsassignmentcapabilitydoesnotmakeanydecisionsaboutwhichthreattrackstoengage,nordoesitissueanyforceordersoverthelinktoexecuteengage-ments.Itpresentsonlyengagementrecommendationstotheuserforthreatsthathehasselectedforengagement.

Performance Assessment and Rapid ReplanningThe prototype AADC current operations module

provides the decision maker with tools to assess theAAWcapabilityof the theaterassets toprotectDAsagainstpredictedthreats.Thesamehigh-qualitymodelsusedforperformancepredictionintheplanningprocessare utilized in the prototype to display the predicteddetectionandengagementperformanceofactualunitsintheaterattheircurrentreal-timelocations.Thisaidsthedecisionmakerinassessingtheadequacyandlimi-tationsofthecurrentairdefenseplananddeterminingtheimpactofunitsnotonstationwithrespecttothatplan.

Because things do not always go as planned, thecurrentoperationsmoduleincludesarapidreplanningcapability to support decision makers in adjusting airdefenseassetstocounterunforeseenevents.Equipmentfailures,schedulechanges,shiftingpriorities,andcasu-alties can all render the current air defense planand any contingencies inadequate for the situationat hand. Immediate, near-term adjustments may berequiredwhileanewairdefenseplanisdeveloped.Therapidreplanningcapabilitysupportsdecisionmakersinmakingthesenear-termadjustmentsthroughawhat-ifdecisionaid.Thisaidallowsdecisionmakerstodraganddropunitsonthebattlespacedisplayandinstantlyviewresulting detection and engagement performance pre-dictions.Thus,near-termadjustmentsoftheairdefenseplancanbemadewiththebenefitofsoliddata.

INTEROPERABILITYEven the best engineered system can be rendered

uselessifitcannotinteroperatewiththeothersystemsin its environment. The prototype AADC capabilitywasdesigned fromthestart toworkeffectivelywitha



Table 1. AADC interoperability.

AADCcapabilities Existingsystems/applications

Communications USMTFrecordtraffic Tasking/mission/JFCguidance ATO/ACO/TACOPDAT JICO TADILsLink11/16 CECviaTADILs

Singleintegrated HDTVoperationaldisplays,battlespace airpicture visualization

Identification NIMADTED/world-wide/cities/topography Overlays/graphics/airroutes/tacticalareas JICOinteraction Operator-definedalerts Replay

JPN TBMCS/CTAPS(ATO/ACO) GCCS(operationsarea) JDP(TACOPDATexchange)

Intelligence EOB/ECOA RFI/EEI TRAP/GALE

Collaboration SIPRNET/ISDN COMPASS,whiteboard,e-mail,Webwith componentcommanders/liaisonofficers

Sensor/weapon DSP/TADILs/CEC capability E2/E3 Weaponssensorterrainmasking Patriot/SM-2/SM-3 THAAD

Missilewarning DSP

Theprototypealsogenerates,receives,andautomat-icallydecodesU.S.MessageTraffic(USMTF)messages.MessageprocessingsupportstheautomaticimportationofairtaskingandairspaceordersaswellasCJTFguid-ance. It also allows plan data to be easily distributedtoothersystems.ThroughthesemessagestheprototypeAADCcapabilityinterfaceswithJPNapplicationssuchastheJointDefensivePlanner(JDP),GlobalCommandandControlSystem(GCCS),TheaterBattleManage-mentCoreSystem(TBMCS),andContingencyThe-aterAirPlanningSystem(CTAPS).

CONCLUSIONThe prototype AADC capability gives decision

makersasetofeasy-to-useadvancedtoolsfordevelop-ingandexecutingairdefenseplansinarapidlychang-ing environment. The prototype has been installedat APL and in two ships, USS Mount Whitney (LCC20) and USS Shiloh (CG 67). Through several JointTAD exercises with participation by the prototype

broad range of existing military systems and applica-tions(Table1).Further,itisextensibletooperatewithfuturesystemsandapplications.Theoverallstrategywastoassurethatresultscouldberapidlyandaccuratelydis-seminatedthroughoutthecommandstructureandthatinformationdevelopedandresidentinexistingsystemscouldbeseamlesslyimportedintotheprototype.

TheprototypeAADCcapability is interoperable intermsof communications, single integratedairpicture,theJointPlanningNetwork(JPN),intelligence,collab-oration, sensor/weapon capabilities, and missile warn-ing.Theprototypereceivesreal-timetracksfromavail-able tactical digital information links (TADILs) andCEC(CooperativeEngagementCapability).Thecapa-bilityexistsforforceorders(e.g.,assignweapons,breakengagements, etc.) originating from the current oper-ations module through decision-maker action to besentoutover theTADILs.DSPmissilewarningsandelectronicintelligenceinformationarereceivedviaaninterface to a ship’s Tactical Receive Equipment andRelatedApplications(TRAP)System.

AADCcellatAPLandatsea,theprototypefunctionality has been refined, taking intoaccountfeedbackfromstaffofficers.Itsfunc-tionalityhasproventobeaninvaluabletoolfortheAADCinperforminghiswarfightingresponsibilities. Use of the prototype hasdemonstrated that “computer-assisted plan-ningnotonlyprovidesaquantumleapintac-tical-levelplanningcapability,butalsomoreimportantlyenableseffectiveoperationalandstrategic-level planning for all phases of anoperation or campaign.”3 Additionally, ithasbeenshownthat“theclarityofthe3-Ddisplay in the operations module enablesthewatchofficertosignificantlyreducetimespentgainingsituationalawarenessanddra-matically increases time spent on decisionmaking,direction,andcoordination.”3

The baseline requirements for the proto-typeAADCcapabilityhavebeendefinedanditiscurrentlyintransitiontoproduction.Theinstallation of the first-production AADCcapabilityisexpectedtooccurinFY2005aspartoftheCruiserConversionProgram.

REFERENCES 1Winston, W. L., Introduction to Mathematical Pro-

gramming, Duxbury Press, Belmont, CA, pp. 120–179(1995).

2Dennehy, M. T., Nesbitt, D. W., and Sumey, R. A.,“Real-Time Three-Dimensional Graphics Display forAntiairWarfareCommandandControl,”Johns Hopkins APLTech. Dig.15(2),110–119(1994).

3Fleet Battle Experiment Charlie (FBE-C) Quicklook Report,NavalWarCollegeMaritimeBattleCenter,Newport,RI(May1998).



THE AUTHORS

JOSEPHH.PROSSERistheSupervisoroftheTacticalInformationSystemsSec-tionoftheReal-TimeSystemsGroupintheAirDefenseSystemsDepartment.HereceivedhisB.S.,M.S.,andPh.D.degreesinelectricalandcomputerengineeringfromDrexelUniversityin1991,1993,and1996,respectively.SincejoiningAPLin 1997, he has worked on the development of the prototype Area Air DefenseCommandercapability,specializinginparallelprocessingtechniquesandautomaticplanningalgorithms.Hecurrentlyleadstheengineeringeffortoftheplanningsub-system.Hise-mailaddressisjoseph.prosser@jhuapl.edu.

MICHAELT.DENNEHYis theSupervisorof theTheater InformationDisplaysSectionoftheReal-TimeSystemsGroupintheAirDefenseSystemsDepartment.HereceivedhisB.S.incomputerscienceandengineeringfromtheUniversityofConnecticut in1985andhisM.S. incomputersciencefromTheJohnsHopkinsUniversityin1990.SincejoiningAPLin1986,Mr.DennehyhasworkedonthedevelopmentofprototypecommandandcontrolsystemsincludingtheAutomaticIdentificationSystemandtheShipboardGridlockSystemwithAutoCorrelation.HealsoledthedevelopmentoftheForceThreatEvaluationandWeaponsAssign-mentSystem’shumaninterface.Heisnowtheleadengineerofcurrentoperationsfor theprototypeAreaAirDefenseCommandercapability.Hise-mailaddress [email protected].

ROGERA.SUMEYistheSupervisoroftheReal-TimeSystemsGroupintheAirDefenseSystemsDepartment.HereceivedhisB.S.inelectricalengineeringfromCaseWesternReserveUniversityandhisM.S.incomputersciencefromGeorgeWashingtonUniversity.HeistheleadengineerfortheprototypeAreaAirDefenseCommandercapability,andpreviouslyledtheForceThreatEvaluationandWeap-onsAssignmentandAutomaticIdentificationDoctrineProcessorprototypedevel-opmentefforts.Hise-mailaddressisroger.sumey@jhuapl.edu.

ACKNOWLEDGMENTS: In addition to the authors, the prototype AADCteamincludesTimothyP.Boyle, JohnC.Briscoe,MarkE.Byrkit,RichardL.CannonJr.,DanielJ.Christine,JeffreyG.Cooley,LTGMarvinL.CovaultUSA(Ret),WilliamC.Critchfield,HenryF.Dirks,EdB.V.Doran,MajGenLeeDownerUSAF(Ret),MarvinE.Drewry, JohnG.Elder,KellieM.Etheridge,FredrickR.Facemire,NancyM.Finta,RussellW.Garrett,JanetM.Goodman,

CraigHarris,KeithA.Hirt,EdgarG.Jacques, JamesR.Lamping,GregoryA.Miller, James T. Miller Jr., Francis W. Murray, Larry W. Nemsick, Hyon W.Park,MichaelA.Pratscher,RobertD.Rein, JohnF.Ritter,DaleR.Shiflett,MichaelA.Simeone,JohnnieM.Sims,ADMLeightonW.SmithUSN(Ret),Mark A. Swana, James M. Tepe, David A. Wallace, Thomas Wienke, andArthurN.Willoughby.

EDWARDP.LEEistheBattleForceProgramsProgramAreaManagerintheAirDefenseSystemsDepart-ment.Hise-mailaddressisedward.lee@jhuapl.edu.

Documents

The Prototype Area Air Defense Commander Capability · Joint exercise experience of staff officerswho have used the prototype at APL and at sea. Planning Module The planning module