World’sFirstMagneticDiskDriveDiskStorageDevelopment,IBMSanJoseLab,1952–1986

hestoryoftheinventionofthediskdrivepredatesSiliconValley.In1952,inordertoattractresidentWestCoastresearchanddevelopmenttalent,IBMopenedanewlaboratoryonNotreDameAvenueindowntownSanJose,notfarfromits

1940s punched cardplant. Within a year, LabDirector Reynold ("Rey") B Johnson andmanager Louis (“Lou”)D Stevensrecruitedsixtyengineers,scientists,andtechnicians(includingafewself-professed“wildducks”), fosteringacollaborativeandinnovativeculture.Theyinvestigatedrandom-accessstoragetechnologiestosupersedeseriallyaccessedmagnetictapeandthemanualsearchingoftubsofpunchedcards.ByJanuary1953,Reyfarsightedlyfocusedthelabonitsdesignforadiskdrive:astackoffiftyrapidlyrotatingdiskswithmagnetizablesurfaces,accessedbymagneticread-writeheadspositionabletoanysurfaceanddatatrackviaoneortworetractablearms,eachcontrolledbyaservomechanism.

While some engineers dismissed the intrepid design as unsound, even deriding it as a “bologna slicer,” Rey steadfastlyadvocatedforitscontinueddevelopment.BillGoddard,anexperiencedaircraftengineer,alleviatedconcernsbycraftingaread/write head that could fly on a compressed air “bearing” merely a hair’s width above the undulating disk surface.JohnHaanstra,aUCBerkeleygraduate(andlaterpresidentofIBM'sGeneralProductsDivision),designedan“in-line”datatransactionsystemcalledRAMAC: RandomAccessMethodofAccountingandControl. Developmental snafus includedadramaticfailureoftheinitialservomechanismandaspinningstackthatunexpectedlydisintegrated,injuringtwoengineers.

Workingmultipleshifts,theIBMSanJoseLabstaffbuilt,testedanddebuggedseveraldiskdrivesduringthespringof1955.CollaboratingwithEndicottandPoughkeepsiestaff,theythentirelesslyassembled,testedandrefined14prototypeRAMACsystems,thefirstdeliveredtoZellerbachPaperCorporationinJune1956.InSeptember,IBMannouncedtheRAMAC305,withitsintegral350DiskStorageUnit(Model1),alongwiththesimilar355diskstorageunitforitspopular650computer.Atthe1958BrusselsWorld’sFair,aRAMACcaptivatedcrowdsbyprintingoutanswerstoquestionsabouthistoriceventsintenlanguages.In1959,toshowcaseAmericaninnovationandknow-how,ThomasJ(“TJ”)WatsonJrledtheSovietUnion’sleaderNikitaKhrushchevonatourofIBMSanJose’snew190-acrefuturistic-lookingindustrialcampusonCottleRoad.

Duringthenextdecade,IBMSanJoseLabengineersdesignedandmanufacturedhigher-capacityandfasterdiskdrives,basedonself-actuatingair-bearingheadsandremovablediskpacks, foruse in IBM’s1401andS/360computers. Bythe1970s,competingfirmsweresellingIBM-compatiblediskdrivesandsoonbegantoofferdrivesbasedonemergingopenindustrystandards.Inthe1980s,IBM’s3380DirectAccessStorageDevice(DASD),thefirstgigabytediskdrive,accruedrevenuesof$25billion.Bythe1990s,thediskdriveindustrywasdoublingdiskcapacitiesannually,shrinkingsizesandloweringcosts.In2003,IBMsoldoffitsdiskdriveoperationstoHitachi,whileretainingitsprofitablestoragesystembusiness,researchanddevelopment.By2018,theindustryhadsoldapproximately9billiondrivesworthaboutatrilliondollarsinrevenue.

Innovationsat the IBMSan JoseLabalso includedthin-filmread/writeheads,voice-coil-motoractuators,errorcorrectioncodesand techniques,disk cartridges, floppydisk,data celldrive,a relationaldatabase (SystemR), theStructuredQueryLanguage(SQL),amid-1970sprototypeofRAID,andCount-Key-Datastoragesubsystememulation. In1986,theSanJoseResearchLabmovedintotheAlmadenResearchCenteratopthenearbySantaTeresaHills,atestamenttoIBM’sinventionandcommercializationofdiskstorage,oneofthefoundationsoftheInformationTechnologyera.

IBM350DiskStorageUnit(Model1) IBM305RAMACCapacity:5millioncharacters Capacity:Oneortwo350Units(5or10millioncharacters)50disks(24”diameter),1200revolutions/min Technology:Vacuumtubes,relays,discretecomponents,Character=6bits(48symbols)+1paritybit 100-charactermagnetic-corebuffer50,000100-characterrecords Programming:20tracks/inch(onouter5”),100bits/inch Upto200instructionsstoredon6,000-rpmmagneticdrumRandomAccessTime:600msecsaverage Conditionaltestsspecifiedbyplug-wirecontrolpanelPhysical:1,730pounds,68ft3 Physical:5,300pounds,220ft3RentalPrice:$650/month(equiv.$5,600in2018) RentalPrice:$3,200/month($28,000/monthin2018)PurchasePrice:$34,500(equiv.$300,000in2018) PurchasePrice:$190,000($1.6millionin2018)Unitsdelivered(allmodels):~2,000350s,~1,000355s Systemsdelivered:~1,300

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IBM305RAMACatUnitedAirlines,1957

PhotoscourtesyofIBMArchives

IBM350diskbeingunloadedfromaDC-7for“ExhibitionofTheAtom,”Amsterdam,1957

DemonstratingRAMACatBrusselsWorld’sFair,1958

IBMSanJoseLabdiskandheadtestbed,1954

IBMCEOThomasJWatsonJrandSovietUnionPremierNikitaKhrushchevtourIBMSanJoseRAMACproductionline,1959