• DECLASSIFIED Authority £13 l $J l NAVY DEPARTMENT BUREAU OF SHIPS REFER TO FILE No WASHINGTON 25 D C 4U ED Jbb SECREl e hoal S L BdOIIILLIB i CoMaa«- I Gnief of tu hna• of lbi pa SubJ Operation Creaaroa41 - Pereonal Ob•• •t1on1 Ret a htll1pe Cont14•al1al Jlemo on tu Atoa1o loab laq f•••• a Blklal et ao Sept 194' J IIIMI 21@Dtl tl911 MR §f EIYW IRBSIIIQII 1 tu experlaealal exploa1oa of ' a oa10 boabs al 81k1n1 Ihle pa t r Jaa• pe1'111l e4 aa wapara11elle4 epportun11J to eTalule the potent1allt1es ot be Atoalo Bo ab aa a weapon d4 lo 4etea1ne fro• the reeult1 ot the ex ploe1oae oa la-val Tessel 4Gargeta wllat eb amgee 1n the de11gn of la-val ab 1pa are d eairable lo 1a -eaee tbelr power to ree1st th11 tor• ot attau I he loat lng 1apoee4 oa Ille 'lal @' et elupa bf the exploeioa of tlleae a oa1o bollbs 41ffere4 from l Ult Ulpoae4 bf oonYeaUonal exploel••• ta IVG u Jor f1r1t the pbJe1oal loa41ags air 'blau t wateP-sboft an4 beat were far more seffN thd ever before exper1enoe4 being or aveb magn1tude as to act on a sb lp a1 a vb ol• rather tbaa aga1nat 1CNU port1on or •••tlon of tu dl1pJ •••on4 tor the f1rs tl•• ship were ••l'JJeote4 to large dlOute ot ra41at1on fl Ofl ra41oaet1•• ulerlala aa4 'to oontaa1nat1on fro• the ra41oaot1 ve 1-produota et the atoa1o exple11oa r••••t•t a lo oae 1 o vs taeaae4 tl'le te ••• oou14 fail to • 111pn u 1e l bf tl'ie deartraet1Ye r ot tu boa'b Tbe ez• ploa1one were -peeb oula and m-1nap1f1 ng Tb e rts1ble aater1al 4oage on •••••1• close to tile polnl of burst wa• extens1Te One raot n oweTer1 beode apparent at once Tb is tact vae that tor both tu alr bu rel aa4 tor tbe nb- nrtace bare lbe u terlal deatr iotlvene•• of the boa'b fell ott r 1dl1 with the 411tance fNII the point of exploaloa the bomb releases vaellJ more energy Utaa oonyent1onal explos1vea 1 s ab1ll y to 4o material 4u • 1a oonf1ne4 to a Naeonably wll Uf1u4 range fh1a Pange laough large vua oompaHI io that ot otber aowa exple•1••• Al though 1• not great lri'lea eoapaH4 lo the d11taneea nonaali Jtep• when naval •••••1• ateaa ln toNat1on 4 fo lntellJ geatly approach the proltl• of laooJ po MTal sblp ·••1t• 11 1ng tu l••··· leaned m t1a11• FROM BUREAU OF SHIPS DECLASSIFIED 1 A 1thority -- £1 3 l % J --------1' NAVY DEPARTMENT _ BUREAU OF SHIPS REFER TO FILE No WASHINGTON 25 D C loi Oe- 'ber lHI tperat1on 11-eearoaAe - Pereeaal 0bdnat1one •• _ - - •• • • 11kla1 eeus des1 rab1e to • • fl rel some of aa ••••• •' of probable nee••• of an a-toalo weapon altaek ag lna naval target tu pro'De1111117 of 1ta eaploJ'Mnt aa4 tb e netare or fora of attaok whltll - 'N expee ea keh • •••••eaeat 1• neoeaaa117 o 4etes1ne the eeve rltJ of the threat of the napon an4 • J•a 1t tor arr g1ven type •1p neh Nd lioa 1a al 11111 o per-fora 1te prlaar a1ea1oa •• relltlll tlle 1- fro• uangea in aaraolerlat 1•• helgned to ooabat tlle threat I be follOW1ng oTerall 1apreea1one d4 op1a1on a an baee4 on obaenal1one at 11tin1 oa oena1a of lnatraua at1on data obtained 4v1a the leate an 4 on ooavena 1ona w1 b o hAJr ••Mrs ot iltP-011 thef are ude in a4•anoe ot a 4eta11e4 _ ot all tu 4ata aecualate4 -preeeat • t a 11 1£ coat • aetv1ng a oaie • anl the A Ule appueatlJ l1a1ted - pplJ ot raw aater1a1 tJ'OII wh1e Ille boabe are llade u ke Ill• •re - a the1r etteot1•enese against lblp t •I• Justlt1ea hea thcn1gb f'llture teetr a1log1oal a4•an••• re41u e the eoat of the ltollb ••4 new soUPOea of t1es1oaable material are toad 1't 1a belS •••4 Ulat tu a1 ppl J of tb eee bollb11 wlll alwa s 'be N1at1••17 11111te4 r rthen on 1Mon ae ot tu aeo1 laa1• of a oha1n reaot1on the o tt arge ot f1aa1onable uterlal 1n an atol 10 boab lla1 a 4et1a1'te a1n1au -4 a practical IIUinm else fh1• tao oouplecl w1'11 the nee4 tor elaborate aec - n1•• to 1a1 tlah na ion aa4 to protect persoanel wUl tend to••• 11111 te on 'the an4 tJP•• of wapona la wh1cdl atoau o explo•1••• oan be use4 Since the 41stanoe between naval ffeeels s eaa1ng 1n tol'llation nee4 be 1aoreatMMl GftlJ 111gll'll f 'lo 11a11 tile nuber of Tee- ex •••1•• •• ••• •J •• aels v1 tbia tu letb al radius of an atold o exploe1on to oae ••1•• or two the d4 ctea1n'bll1'7 of thle tor• of a1 aek troa a 11111'brf e ad polal 11 aer1011al 7 c••lloaecl ' The aloa1 e bomb aa4 ato1o weapon a W'l'l1oh aq be 4e•elopect in ta f l 111'8 •••• ll1Uth MN valuble for aaplo1••n agaust elrateg1o a • 1a a ooatrr•• 1n4ue r1al d4 peplllati oa •ntere ratur for ••• aolloallJ' agairual a ell1p or a well 41sperae4 torat1oa of Bh1P•• fha possible ••• of atoalo weapons againa lhlp1 al sea hw•v•r• oanno 'be 41acoute4 eat1rei -·- FROM BUREAU OF SHIPS I • DECLASSIFIED q l 'js J A ethority REAU OF SHIPS NAVY DEPARTMENT LR TO FILE NO 4i24 DB Jbb '- BUREAU OF SHIPS WASHINGTON 25 D C ORY JY 1TED TBS NDS SECRET Operatloa Onearoad• l'•rtonal Obaenatlone Oil 111• Aten• Boa'b •• • • Bit1a1 ----·------------------------- • l' teeta are supported troll 1no N baaes and •• •••l• 1n port tor tuellng talnag on aler•• •• r•patra will M 1001deatal largete in attacb on such baeea or oa Ille 1n4uatr1al areas aad popuJ at1on uaters vhieh 1a many •••• aN oont1g1o•• to 811Cb 'btutee A aaJor aaph1b1oue operation in whlch la ra• n uibera of ship1 and personnel are eoneeatrate4 1n a relat1Yely Sllall area would he a worth wll1le targel tor aa atoa1o weapon allaok It ••••• llkel - that nob attacks ¥111 be bf aerJ al lloab1ngs or bf roek ets en4 ga14e4 1111a11••· hr Ille attaek againat waterfront areas aa4 aapa1b1ou1 operations rn1•a11•• vb 1oh are dealgud tor nbavtaoe exploeion• appear to otter tile Met preapeete of effeotlv•••••• The 81ll un1rtace shot at B1k1n1 th11 ·past summer vaa flr•A at a deplb ooaa14erab1J l••• thaa the tne retleal optlaa tor • a aim 4asage tu gae babble formed lJF tile explo•1on Tented tarollgla the eul'faoe 1-tcre it reaeh 1t• aaxi IUII nag• else IYea so lte letbal rage 1 tu 41stanoe at wh10A 11 aank 1b1p1 va• almo•t •• great •• that ot the alr burst for eurtaee ship• an4 1 sank submerged submarines at 41atanoee 1ta lethal range tor avfaee alllpa Al though aater1al to surY1Y1ng ahipa was l••• Ylde spread thaa 11at oausd a1r burst 11 ••• 1a aoal oa1ute ••h aore seven la 1 ta of the abipa s111tarJ etteot1Yn•••• be7oa4 4•age bJ the etteet l'ertaape Ille ••• algn1t1oaat ad threatening a1ngle teatve of an atoaio weapon atlaek brought'° 11gh't bJ 'Che leata at 11k1D1 was the heaYJ and p•r•l taat racllolog1ea1 oontalaa- - a- FROM BUREAU OF SHIPS u DECLASSIFIED • A tJthority £l 1 l i J 7 j MY DEPARTMENT _ - - ---- -- - -- -- -- BUREAU OF SHIPS NAVY DEPARTMENT - BUREAU OF SHIPS FER TO FILE NO WASHINGTON 25 D C -----------------------------11•• of ta rget v••••l• avvlnng Ille a• baUl'faoe lNrs the '11a1oa prodv eta ea nppe4 ta '1l8 water wre e rne4 up 1a u plue aad 41sseld aate4 througb o•i tu lagooa AlUloug uasuNaeat11n41oate4 that the pert1oa et tlle f1aa1on pN41aet1 10 entrapped w u relat1•tlJ aaall oal J a tn b 11u1 110e of tllea on the •P w1n4 hi age et Ille_ •••aped Jla41oaot1v1tf ••• M intense oa aan of the ahlpa lhat th•J coul 4 be boar4e4 tor onl 7 brt er interval a o- er a per104 of neta and 1a aou oaaee aon th 1 • 1 IN lsu romar 01 of bU 1'1r11S miAi lAI 3ttag 01 s111rll 1 1111111 ia n Mt • The overall ab111' t7 of the target ship• to vi etand the loa41ng 1apoeed lV' the atomic boabe wa1- to tu IIOa optoa1at1c expeotailoaa lll1pa were Mt atoa1ae4J t1W7 414 not 41a1ategraie nor did hey glow with 1nduee4 ra41oaet1v1tJ ¥1th tll e exeept1on ot 18 IAGATO which 1aak tr• pPOgNes1ve tloo41q t1ve dq1 after Iha aabsurtace 1hol all the vessels ll Jllnk were subJeoted to loa41nv a greatlf la of that whlu lhe7 were 4ee1gne4 to willlsta 114 The above la aot 1ntelld ecl o 1mp17 tbat u lrlprov•••'• la 4ea1p were 1n41oate4 bJ the 1esla ••h val•a le 1nfo naat1oa and 4ata was o ttalae4 on the nlalive abil1tJ of the var1o•• ooapoaeat• of naval ve1aels to defeat the lapoaed loadlng Weak po1nte vere bstought io l aa4 lines of 1nveet1gat1on tor f111'1 her a'q4J we re 1ad1oa • It 1a felt howe- er tbal no ra41oal or •Jor 1a be 4ea1ga of the tXpoeed •• h 1-gele was 4eaon-etrated ae 'belng n• ••• 17• la general 1 1• believed that tl e tests 1nd1cate4 our current design of ak1ps etruotUN la ao'Wld aa4 a4e1uate an4 illat ht re 4•••lo paeata sboul 4 N ••olutloaar rather thaa n•o1at1onar ex•••• •ans• 1 •• IJ SIJl IIIOl IE 1 8 t rt ee ••l• la lran drtcl l•a41ag m AD Mi IVBRlfMFI 1111 • A eoapar1 oa between tl'le air buret and ille 1111 wrai in Nla 1oaah1p to '1 e11' efteot oa ta• arget Ye ooapl1ea e4 bf he faot tu I the air lturat ••• eevel al t-he character ot how ver was clearl 7 cllecernabl• 7ard1 atl8J' troa the pcd 11t intended ilaposecl bf eaeh ••as•I was sot la tile can ot Ule alrbvat tu pr1aar ••••• •t ezplo- tile air blaat or air s hoet asaoo1ate4 w1 h tlle FROM BUREAU OF SHIPS I i DECLASSIFIED Authority q l 'bJ DEPARTMENT REAU OF SHIPS NAVY DEPARTMENT - r BUREAU OF SHIPS iR TO FILE No WASHINGTON 25 D C 1 Oetober 1946 V 0peral1oa Croasroa4e - 7eraonal Obse at1ona on the Atoa1c Bc uab tests a B1kln1 tlons The air blRat pea presaure aa eeasved bf vanoaa 1ns ruaents at 1Ut1n1 wa• on the order ot 100 lbs p r square inch at 400 7arde trc a the toot of the burst 1 e the point on the SllJll- tace d1rect17 low the burat 1 dropped to about ID p a 1 al 000 Jards was abo•t 20 P• a 1 at toO J' l d a aa4 1 p e 1 al 1100 yar«a htensiff a'bov• wa el' •• • was general on target ship a wt thln 900 7ar41 et tbe foot tf tile 'tnard le7ond that 41elaaN the daue• tor the mod·part Mtpertteial and 414 not gNatlJ affeoted the f1ght1ng ett101eno1 ot lhe eblpa the nature and 11nertt7 of tile cta11age var1ed 4epen41ag on the '1' P• of eblp aa4 upon be ebip• • or1entat1on nth respeot to tu 41r-ect1on of ltlast · wa• 3 nve vessels were nak bf' 'the air beret Of' th••• 1-ILLlAH APA IV al alltou 100·1arc111 aealt v1tll1A OM a1 nute ot the 1u ot the explos1ca file CARLiaLB aaotur APA al about 400 7arde sank Within a balt hour ot the explosion A1fDBISOI DNll at about 800 Jar4• rolle4 o•er an4 sank wltbln about I •1nutes after tbe exploa1n the LM OI DD367 al abo1lt 700 Jard• cap111ze4 W1Vd n liO atnutee after tbe explos1on an4 aank soae hours later tu SAi AWA aa ex-lapaaeee CL 1111 1£ atern to the exploaS on at a 411Jtanoe of about 4 0 Jaret sa nk 26 hOurs after the exploe1on the •• Ot the eun1Y1JII lll1ps Ute 4aaage lo Ule tollovt 111 s1ga1f1oanlt Ytseel• 1• pemape the ••t a fbe nlaarlne Jbfl al about a80 Jal'd s was a • - 'bl ea lopa14e 1t1'1h euob of her nperatruo1ure as ••• not w1pe4 ott 41alorte4 and twtete4 b e atrengtll lml 1 uv••••• was 1ntael1 au Ille •••••l wa1 gottea ·anderwa on bolb ear1aea witac n 11 41tt1cal t1 van tu orew re- turaed aboarc 1 'b The to 110 a eenerete 011 barf••• about '460 yarde was deao11elutd '°1 114•• wt the b 1 ntterecl no aer1 o•• Aaaage o Tbe lJ U 1 PDDEJfOE CYL 2 al about 580 farda vaa aeanl7 daaa ge4 abffe water along the port e14e and oa the flle' lt aad hangar ct eeks with ael'lous etnctural 41akri1on dowa·througtl the third deek - •FROM BUREAU OF SHIPS l DECLASSIFIED A1Jthority I ' jllS q 3 l %J NAVY DEPARTMENT BUREAU OF SHIPS NAVY DEPARTMENT BUREAU OF SHIPS REFER TO FILE No WASHINGTON 25 D C ------------------ -----------at abov 'Jar4a tAD 4 Tbe PDSAOOLA 780 1 the SAL CU at about 900 Jal'de the AKlAISAS at ar out 650 7al'd•r- the IEVAnA al about too JaNs tm ff'end 1noapac1 atua ataok uptake and 13o1ler daaage ae ral w1 ui14•• dallCand serious dis ortioa ot '119 aa1n deek ana aappor 1ag aln e lNS e he ClUffbDSI aa APA al abov i 600 Jard a sutteN4 topside daaqe a114 eona tderablt 41alort1on in the va of nwaber one hold but wae not 111mobll1ae4 •••1• a In addition to the daaage 'bJ ai r blaa fire• 1gn1te4 1A Arif 4 uirtenaster1 s«tt•rid R oaed tor te t and 1a oor4 • and fender bf the naeh b eai veN 1114• apl'ea4 111 rougb ou t he arra occving ••tar•• MOO Jard• troa the polat of burei Because the target ehipe were l•aaned illeae t1na ao•• bli rne4 Wtcb eoked and 1n eoae oas•• oaus•d modera e eeeondarf 4a11age he etrecl ot the tlalh hea oa exposed pereonnel wotll 4 probab J b sYe been sertoue out io Nffi•• of about 2000 rarile wl anr screening at all would have mat•rlal 17 reduced oaeual t1••• Standard l 'Yf tlaell pNot clothing is bttli•Yed to be a aat1eta tory •ea sure to protect again el ih is heat 6 fher e was no evidence of a1p1ftout water u ook and no peraistant ra41olog1cal eontrun1nat1on of targ•1J shlpa • Aa evidenced bf 1 ts etreo't on ta• aniaal s expoaed tor the tea the ra41a 1on t10• the bur1t 1 selt appears to have been le'1aal ohietly to a n1mala whioh were not Preened t roa d1Ntel attack lo 1nd1cat1on or a1sa11e da lage wae noted It ls interesting to not• at thi1 po1nt that even the vor1t duaged sh1pe VV1Y1ng the alrbural were able to atea uder their ow pc wer aner oal7 mo4era e N palre 8 Ka teri l dulage fro• ue aubaulf'ace 'bur t waa predOllinantlJ trom water shock v1ta no evidenee of flaab heat an4 only 111 nor 1nd1eatlons on eurv1v1 ng sllips of a1r blaal 4aaage the the SARATOGA at abotal 100 1flMlf lhe d l' dSAS a I a'bout 250 lllrda ro 160 a 600 7aP lw and the tn tba•rged e t'bma1nee PILOTFISI al 400 7ards APOOOII at 8'50 fardt and SllPJAOX al 800 JaJ'de were sWtk 1n tb 1 a lest Th• Lot 111 ft at allJoat 100 7arda wa1 •apnaed but noate4 bottom up until aak 1v 4••ol1t1cn obarc••· the IA lATO at 800 78J'4e alee sank t1ve daJ• after lhe exploa1oa tru p rogNuu1l Ye tloo41ng 1thloh -beoa e or Pa41o1og1eal oond1- - - FROM BUREAU OF SHIPS - l ' DECLASSIFIED I i Authority __ Cf 3 l i J I BCRERC Ci NAVY DEPARTMENT BUREAU OF SHIPS REFER TO FILE No WASHINGTON 25 D C ----------------·-------------tioaa oould not aontrolle4 the water't1gllt 1ategr1 ot lla t be IMJ ATO w2u1 n oi good there waa some noo41ag 4v r1ng tile a1Jt burst troa which the dip atlfferecl no ude r - ter 4 9 8watap1ng 'bJ the t ona of vater 4eeoen41ng tro• tile plue po111bl• ooa'tribute4 eoaewhat to the rap1d1tJ w1th which w SAl lfOGA and a to 180 aank 10 Ille tao '-al tbe AtOIOI d4 SIIPIAOg WN euk while the GASCOIA DI PALLOI IVGBS aat LSI 133 at oons14•ralt1J lesser distance reaa1ne4 atloa eubstaal1atee the 1nstrumenta- t1on data that b e peak water shook•••• pNeRN 1e atteole4 bf the air-water lnlertaae and tiult befoa4 a zone 4•t1ne4 bf a epeo1t1o engl• of 1ao14•ao• of the shookwave vita i be ••••• au rtace th• preatnare 1a Nt4taoe4 ooru11ura'bly llelow 'that wtuola migbt be exp•ote4 troa an aocouat1cal tbeor fbis atfeot on peak pressure edead a to great•J- 4eptlle 'below Jae au-tao• witb an 1aorease 10 411tanoe trom the ar111eal sone · a 11 lfaler1al 4alla«• euttered bf' the tn i-t'lv1ng ah1p• was confined to sb 1ps within the 1000 7ar4 range an4 tor • given dJ stance troa the wrs waa DtOat ••••re oa 4eep draft tlblpa ' be PJ BSACOLA al about 800 J'ANee__ he llUGliES ai about 660 T•l'lla a ad tb t GA5C0 MAJJE an4 JALL 011 at oou an4 600 Jarda reapeoli'f'elf all suttere4 aaJor maehiaer derane nle wb1ob woul4 have re- w red extens1 Ye oYerb a tl e to Nt a1r ror the 4epth ot explosion used at 11 tlni the ran • ot 1ncapao1tat1ng daaage to eur- tace ab 1pa vaa about 800 7al la 12 the ra41olog1oal contaau nation of ibe targei Teeeele 'Wb1eh follove4 the Ul4ervater burst waa the most eta rtl1ag an4 tbreaten1Jl€ aapeot or el tber est Wi ereaa 1a4leat101us or NCUoaotl Yi tJ on targe vessels after tlle alr burst we re oont1M4 lo ••enels close to tu point ot bltrst an4 dropped o within the pertai ttecl tolerance on all Yeeeels w1t1Un three dqe '1le ra41o1og1oal conl dl1na 1on which toll « the nbaurtaoe tur ex en4ed lo vessels beyond the 4000 Tard• ra41 ae and was so ile 'f1 and perl1stent tlla't • • ' 1iarge vesnle eoul 4 be t oaPded fop only br1ef' interval oTel' a period ct weeks Although tbe efteote of oxpoeure to rad1oao 1v1t aN not lmme41a e the Are none a less certain and had the taJ IW sbip• been • nn• tbe ewntual leas ot 11fe M4 oon1e4 1 ent loas of 11ll1t'iar •tt101enc7 would llave bee n Jd gt -' FROM BUREAU OF SHIPS I· I DECLASSIFIED Avthority q 3 l g J ODR BUREAU OF SHIPS NAVY DEPARTMENT BUREAU OF SHIPS REFER TO FILE No t ECREJ'24 S bJ WASHINGTON 25 D C ID Jhh 1 1946 Operat1on GJ101aroada • Personal Ob•el 'f'atloaa oa ille Atoaio loab Testa at Bikia1 13 As a1pt be ezpeoted the hea•l•$• eoneeatPatlona were topsides but not incons14erable aounta toud their we into the interior or the shipe his penetration probabl7 woul4 llave been 1nor astt4 ha4 the ships been maane4 because et rad1oact1ve matter drawn 1n tb rotagh Y nt1lat1on eJstcnaa and carried into the interior epaeee on the shoes and olotlung of Iha oPeW On the other band bad the crews been aboard an l aware of the danger• present the degree ot conto1nal1on aigb t have been oons1derabl y Nduoe4 DJ' prompt aot1on 1n vaahiog down the exterior ot the ships before tb e ra41oaot1ve matier 1tad opp0rtun1t7 to adhere to the tntrtaoe 14 The nature or rad1oaot1v1tJ ie n1oh that natural or induced radloactive eleaente can no have their rate ot radiation altere4 by chemical or p IJ'slcal means lveey substance looeee r 41oact1ve propert1es at a speo1t1e rate which detenr 1nes 1ts •ha1r-11te 1 1 tlle t1a reqv 1red tor 1 e r-a41oaot1v1tJ to decrease bf halt The hut lite ct so•• elements 1s a tetr aJ nutea while other elements b av1 a halt life ot man thoueand 7ears Tha rad1clog1ca1 deeontui1natioa requ 1 rea the m eehanleel r aovnl ot the rad1cut1n material fhia 1a rent ere4 doublf 41ff1oult bJ the extremely IIUll aiz e of' the particles tnvolve4 111 01 s101 c1A1t 1 11mcAto Al • rtttNJd 21 m nr u r isza 1 the onl J reallJ ••v fae or 1ntrod l0t'd 'bf the 11kia1 leste 1nto the problems cf 4ts1galng n val aaips 1• tha't ot the ra41olog1eal contaataet1on wh1eh tollewe4 t1'e ••baurta • burst As baa beea • at1oned earl lei- deoor rtu1nat1on 1 a 4ltf1cul I lMtcause et tbe 't·er small a1z e of the radioactive part1• oles and tbe taet that their rad1oact1v1ty oaano be red•oed oi- el1111nated bJ chem cal or pl'qeioal •••••• ltdie1 of thia problem an Wl4erwq al the pr uuta ttae What lines they art tollow1ng ls aol known b tt 1t wo tld see11 desirable to 1n el lde tbe tollow1ng broad oa aprleat PN-ventlon of 1agress o r rad1oact1Ye 11a erial A 1ato the fi b1p by i llS N•n1ng ot openings 1• the traoture 2 Use ot tilter 3 •e• ot air pv1f1oat1oa a ad ne1ro lla• lion lo pena1t •1os1ng ott Y11al apacee fro• the oute 1de atmospb ere q•t••• FROM BUR' A OIII SHIPS DECLASSIFIED · A11thority _-1 _ l ZJ BUREAU OF Si ill J Ci NAVY DEPARTM£NT BUREAU OF SHIPS REFER TO FILE NO l • ED tbh StCRET 8ubJt WASHINGTON 25 D C lt October 1948 Operation Cro1iu1roda • PerNnal Obee at1one on the Atomic Baab feeta at B1k1ni 4 tndoetr1nat1oa of Pernonnel a Develop•nt or s lrlaoe punts or coatings wh1•ll rill 1nb1b1t the adsorbtion or abaorbt1on of the rad1oaot1Ye panioles b7 exterior surtaces O l eYelopJHflt of 11f u1ds which w111 take the ra41eaot1ve eubst 411cea lnio solution and enable washing them awaJ D Provision of reliable lndicating and meaaurlng dev1oea suitable tor gefteral eh1pboard uee 111 det•l'lll• lag the loeat10n1 ud eoneentratioaa ra41olog1cal aa- aaJ'd I Arutl71ing the material damage done to the tuget ah1pe al 11k1a11n oonnect1on with the air aad water shockloe d1ng data fr m the 1nstruentat1on program 1 t appears tb l the m1n1aua d1etanoe fro• an atoll1o explo11on '1lat a ah1p caa be w1tb out sutter1ng 1no c c1 ating 4 dlq'e 11 not anioepllbl• 'Ge 1n1oa re4uet1on wlthcut • ag euch draet1c ah1 Dgee as would serlousl1 handicap a giveR l7pe in he perlorat ace ot 1ta aia11011 lino• at the pnseni ti•• ther 1a no Nut1on to do abl tht val 141tJ ot the m1se1on tor whloh ovr naval types are d a1gned swoh ohangee appear tlllY1se and uwarranted The «ans•• radius ot an air explteioa for •oat types appears to be 1n the neighborhood ct 900 7ard1 where the air p resa•re ls about 20 p 1 1 fo reduee thal radius to 100 JAJ'de when the a1r pret1ure 1e about 51 p s 1 would r•tulre a trtatndoue aaount of etreagtb fU'i1 ng Thi I Wllld JlfUUl oa the Hille di spl•o•at nt lt •• guni leas armor less oargo fevtP planeat tew r troop or •aller o rulalng radius or a ooaW nattoa or the above recilaetioa A1 houeh some 1aurovemeat 11 pose1blt the moat etteotive w q ot aeeltng the bomb destnctive th Natl oerta1nl7 tlle o leapest ti-oa t standpoint of etteet on a sh p 1 e ab111t1 to carry ou l lt mles1on le lo 10 d1$ 0le ship• tact1eall1 tbal onlJ one OP two will be exposed to an atomic attack at a time 3 there were boweTer maa l•esone to be learned tr• the Nault• of the leets ai 11k1a1 alld a ruaaber ot local vealt- aese 1a our 1la 1p1 were h1ghl1thted aN 41sc •••d briefly below The m N •al1 nl or these -•FROM BUREAU OF SHIPS ' --- - - DECLASSIFIED Aethodty _ q 3 l 3 'i J _ L BUREAU OF SHIPS NAVY DEPARTMENT BUREAU OF SHIPS REFER TO FILE NO WASHINGTON 25 D C 14 October 1948 a The v1dt spread daaage to stacks aptakes and boilers rea ll ting trom the lr burst uri ts elose study' Daaage to staclta vae 1n on sea tranall1ttett dovn to tht l lP altea while boiler air oaeing were 1n aome oases r ptu re4 were other daraage to tllft ship vaa ot a m1aor nature In general the pressure par-ta of the boilers 11 lftered ao da11age from air blaat b Wea Iller doors and door traae1 were a point ot weakness Develop uata ab ould continue to produce 4oor· aaaeably wh1oh vlll be as strong as a4Jaoent panels ot p1a 1ag o Olea a-up topsides on the upper decka Beduce the aaount or clutter aear lockers mov1ea boothe and similar n1ase1 work 11 an unneoesear7 ha11ard under air blast 1 read11J becomes a m1es1le ui ard to peraenael awl aaa- block v1 a1 aeceases when the7 are ue4e4 aoat Cor4 age aawaera tender eto are a fl baszard but a topsldea atow•i• tor hem 1s considered preterable prov1d1Di the7 are nol near oilier tlamable •teriala fb e t1rea wh1oh followed the a 1 r burst would have beta negligible had crews been aboard the target vessel d Bounded surfaces performed much better under a 11' blast than tla surfaces and should be vorke4 into deelgna where praot1oa'ble Topa1des plating should be aa uavy u4 aa 11 atiffeQed as weight ea4 etab111tJ oons14erat1oaa perllil e Alreraf elevators'on carrierA should be made more ged the SAEtlfOOA which vae ot1tside the 2000 tor tile air 'burst autte Nd a derangeunt _ ✓ oaro '11•circle au oaatio f•llow wp aeohaa1e1a •t her elentor whiea JH''trrenlect 11a operation until the detect1 •• part vae NJIOYe4 Altb ough the elevator ooul4 then be opez- ate4 M't11faoior1l1 by b and the reaoval ot tile part reqld red about tour hours he elevator was s1a1lar to - t ne t7pe lnsiallecl in iSSiX class earr1ePs he der ng• aent was eu11t14 by a1 nor 41atort1on or the elevator pla font Alth Hilgb elevators now being ctevelop•d tor the neav1er plaaee will 4 oubtleaa be aore r1g1d cons1d erat1on 1n taeir deelga sb o•ld be gt vea to air blast 1oa41ng - 10 FROM BUREAU OF SHIPS I DECLASSIFIED I -- q 1 l cg J AJJthority I BOl L o _ _ _ _ NAVY DEPARTMENT BUREAU OF SHIPS REFER TO FILE No V WASHINGTON 25 D C ------------------------------illld iee eho1114 bt eontinue« 1n the shock mounting t of' 1uu hine 7 and eq111paent In genel al the performance ot shock mounted equipment exceef ed eX ectal1ona The traaamesion ot s b ock t•rou h th 1h1p1 structure to loea t1on1 NJIO'te from Ille aNae Gt loading did not pro•• to be a major 9ouree or damage 1n e1ther test ffeaV7 eq i1paent and aachinel'f 110unted en or 0101• to the l wU siruotur• below the vater11n aurrered heav117 1n fflll'- v1v1ng shipe close 10 the subsurface burst llDd th• shook proteot1oA ot no equ1paent requires JJlproveaent g Eleetron1e ect¥1pment stood up well here any eoreea1ng or lh1eld1ng wiu pre ent Alltenna1 and radar epl• nere oan be JtOTt d to 'lllf'1 tluitartd higher air blast pre auNJa Vbip anlennae appeared euperlor to string antennas h The •st etreet1ve m•um f bottom pl'Oti et1on r rlarge ab 1pa ahottl 4 be v1gonousl1 soug·bt The balance between 11Ult1ple bttlll be 4 s1de protection Ad 4ouble bottoms ooapartaentat1on ould be rertlf' fed fh1a question is alread1 Wlder study 1n eonnect1on wi ill influence explod ers for torpedo warheads and 111ne s aA4 '11• 1 uu1ona learned tro• these stu41es 'Will be •qu 117 appl1oa'ble in oombatt1ng the w ter shook pressure ot a au bsta rfeoe atoJlie explomion • 1 the hateh perrtotnu on the tii- rget KIA ere too e s117 d1elodgect Moderate to minor 8heck sent them caaoadlQC do ll'll into the holds Where tbeJ d1d considerable damage to test equipment •d 1netruments J The 4••1ra of••• ohesle an4 eh•ll eenneotiona belov the water 11n• with the1r attendant sea valves ebould be the avbJeet of 0101• acru t1n7 fheee are po1nt of 41econt1nv1ty and hence ot poae1ble vreakness ucler wate sboek load1ng ftleJ sbcul4 be des 1gne4 to be al lea a ae f trc ng as the ad Jacent panel• ot rlai1ng but shot1ld not form hard 1pote a 'ound wh1Gh the pla11ng will r•p urt or teaP S B IATODLLD CC fo•andeP V S l Yr • NM nr-1 FROM BUREAU OF SHIPS -----