technicalinnatureincludedthelimitedtimeavailableforlivevideodownlinkandtheobviouslimitationsin viewanglesandzoomofthefixedvideoandstillcameras,neitherofwhichpresentedsignificant obstacles. Themostnotableimpediments encountered innon-technical areaswere(1)thelackofaclear definition/understanding oftheorganizational structureanddecisionmakinghierarchyoftheverybroad anddispersedsetofpersonnelandorganizations involvedintheinvestigations andoperations, and(2)a limitedandpoorlydefineddownwardcommunication pathtothedesignteamandanevenmorelimited andpoorlydefinedupwardcommunication pathtotheoperationsteamduringcriticalevents.Certainly, thefranticpaceoftheactivities,thecomplexnatureofthemissionandthefamiliarityoftheprocessesto thoseinvolvedregularlyinthemallcontributed tothelackofclarityintheseareasforthedesignteam.To preventsuchorganizational andcommunication issuesfromimpedingtheprogressofaninvestigation, thedesignershouldbepreparedtobeforthrightinaddressing suchissuesearlyanddirectlywhen involvedininvestigations ofthisnature. Althoughsometechnicalandnon-technical limitations inthemannedoperations capabilitywere encountered, thebenefitsofthehumanpresenceinthetroubleshooting andrepairoperationsallowedfor anextremelyswiftandfullysuccessful restorationoftheISSsolararraytoitsdesigncapabilitywithout impacttosubsequent missions.Therapidcollocationofskilledandexperience EVAoperationspersonnel withthehardwaredesignersfrommultiplecompanies wasinstrumental inboththeswiftnessand completeness ofthissuccess.Inadditiontofamiliarizing thereaderwithmanyoftheimpressive capabilities availablefortroubleshooting hardware,someoftheorganizational andcommunicational impediments encountered inthetroubleshooting willbedescribedinthispapertobetterequip mechanism personnelinvolvedinfutureinvestigations todealwiththeprogrammatic issuesasquickly andeffectivelyasthetechnicalissues. SolarArrayDesign Background -"Howitwassupposed towork..." Desiqn Description Thedeployment oftheISSsolararrayincludes bothplanned EVAoperations forrelease andpositioning ofthesolararraywingsandautonomous operations fortherelease, deployment andtensioning ofthe solararrayblanket andsupporting structure. Thefinalportions ofdeployment areautonomous and include themotordrivenunlatching ofthestowed flexible solararraypanels, themotordrivendeployment oftheextendable mast,andfinally,themotordrivenapplication ofthe"high"tension (deployed preload) tothedeployed S/Apanels. Inaddition totheactivemotordrivenmechanisms thereareseveral passive spring-activated mechanisms utilizedtoprovide propermanagement ofthe164flexible solararraypanels andassociated structure duringdeployment. Thespecific sequence ofdeployment isillustrated inFigures 1and2anddescribed inthefollowing bullets: •Multiple payload module operations areperformed toposition thesolararraywingstoclearthe Integrated Equipment Assembly andassociated hardware (notshowninfigure). •EVAoperations areperformed tomanually release thenrotatetherightandleftsolararray containment boxes90degrees thenmanually locktheminplace(Figure 1). •Threelaunch lockretention boltsarereleased byEVAoperations tofreetheMastCanister's Tip FittingfromthebaseoftheMastCanister toenablethesubsequent mastextension (Figure 2). •TheAstronauts arethencleared fromtheareaandapproximately sixthousand pounds ofpreload required forthelaunchrestraint ofthestowed solararraypanelsisrelieved fromthepanelsbythe motordrivenLatch/Unlatch Mechanism overapproximately fifteenseconds. Linkedtothisunlatching motionaretherelease ofsevenspringloadedBlanket Restraint Pinsandapositioning oftheBlanket Tension Mechanism intoa"low"tension mode.Thisisdonesequentially ononeContainment Boxata timeduetoavailable powerlimitations. Ground available telemetry fortheseevents includes motor current timehistory, latched &unlatched limitswitchsignals onthelatchmechanisms andretracted limitswitchsignals forthesevenBlanket Restraint Pins(wiredinseriesduetochannel limitations), although onlyata0.1Hzsample rate. NASA/CP--2002-211506 170