quicklyuntilthedamperdeadbandistakenup.Atthispointthedeployment slowsconsiderably. Ifthe hingetorqueislowandthedeadbandissmall,thetripwiremaynotpayoutfullybythetimetheSARM andLbracketsapproacheachother.ThedamperdeadbandcanvarywitheachinstallationoftheBoom onthevehicle,makingthepredictionofdeadbandstrokeveryuncertainforon-orbitdeployment. Oncethemodelwascorrelatedtothedeployment testswiththeimprovedtripwireandhook,thenominal andworst-on-worst flightsimulations wereperformed. Thenominalcold-temperature performance forall Boomshadapredictedclearanceontheorderof10.0to12.7cm(4to5in).With15parameters being varied,theworst-on-worst performance, notsurprisingly, resulted inahang-up. Asensitivity studyofthe parameters wasthenperformed andthedominant parameters weredetermined. Whenonlythefourmost dominant parameters weresettoworst-case, theobjective ofpredicting clearance withareliability of 0.999999 wasachieved. Lessons Learned Thisdeployment anomaly provides manylessons tothedesign team.Someofthemareobvious and reaffirm basicaerospace practices whileothersarelessobvious andperhaps morevaluable because of that. ThefirstlessonisthatanySTEusedduringtestingshouldbeinspected andrefurbished atappropriate intervals. TheBoomdeployment testshavebeenoccurring foraboutadecade andtheTMcomponents hadnoplanned maintenance procedure. Someofthiscanbeattributed tothefactthatseveral engineers havebeenresponsible fortheBoomovertheyears.Thisturnover tendstodrainknowledge and familiarity withthehardware. Awellwrittentestprocedure shouldidentify possible problems andinstruct theteamtoconduct theappropriate inspections priortoreuseofSTE.Everything frominspecting for component weartoperforming torquehysteresis plotsoftheoffload system areitemstobeconsidered whenwritingatestprocedure. Ground testanomalies arenotallbad.Inthiscase,thedeployment testanomaly alerted thedesignteam toafailuremodethatwasneverfullyappreciated beforethisincident. Thisledtodesignimprovements to increase margins. Thelessontobelearned hereisthatthecostrequired toconduct extensive testson everysinglepieceofflighthardware canbewellworthitifthetestsidentify apotentially serious problem. TheMilstarprogram wasrequired toperform deployments athotandcoldthermal vacuum conditions with everyBoom. Incontrast, manyprograms areunderpressure toqualifyadesignwithaqualunitandthen doabbreviated flighttestsinordertosavemoney. Ifthathadbeenthecasehere,thedesignteammay haveneverdiscovered thisfailuremode.Inthelongrun,eliminating testscouldendupcosting more moneyratherthansavingit. Animportant waytoreduce theriskofanon-orbit failureisthrough deployment analysis. Deployment analysis andsimulation ishelpfulinidentifying designsensitivities thatmaynotshowupintestorare difficult toverifybytest.Perform, asappropriate, atorquemargin, kinematic, dynamic, and/orclearance analysis early.Thiswillhelptoidentify sensitive parameters, determine ifothertests,procedures, or requirements areneeded, catchproblems withadesign, oranticipate test-related problems beforeitis toolateortoocostlytomakechanges. Special careandkeeninsightmustbeusedwhendeciding whichtestsarevalue-added; keepinmindall ofthevariables thatcouldaffectthetest.InthecaseoftheBoom,thereareseveral variables suchasthe leveloffrictionintheTM,theamount oftorqueinthehingesprings, thedamping inthedampers, etc. Onecriticalvariable istherouting ofcableharnesses, especially whentheyareroutedoverhingelines. Special caremustbetakentoensurethatharnesses arenotoverstressed orimproperly routedandthat theyarerepresentative offlightgeometry andconstraints. Also,cableharnesses usedduringtestmust beinspected toensurethattheyareproperly routedandthermally controlled asneeded tominimize their influence onthetest.Tie-wraps areoftenusedtocontroltherouting ofcableharnesses butcaremustbe takennottooveruse tie-wraps. Tie-wraps aregreatformaking neatandwell-maintained harnesses, but theyalsomakethecablealotstiffer.Ifthiscableisrunoverahingeline,theavailable torqueofthehinge 248