-- SilRET D00033904 T ' sns • - - '-· - F-t p DEVELOPMENT REPORT ' ' Thlfl dl•'-·u n11 nt ·1111 i 11 restric-tcd data nn- ' 1 u•r y Art nf l 1j 1 l lSWJ aaiMrrtff' lilo tho disclosure vr its i nlt nt in · pers m iK proh ihl -- -· RE CAiff · - CONFIRMED TO BE UNCLASSIFIED DOE OFFICE OF CLASSIFICATION DC Hix AU-63 DATE 9 30 2014 '- SCL•DR-65-5 REPORT OF MINUTEMAN ACCJDEST INVOLVING A MK 11 RE-ENTRY VEHICLE AT SITE LIMA n DECEMBER 5 1964 R K Petersen 8141-2 Sandia Corporation Livermore Laboratory MG A' FOMIG e • T m MA-t- BS 8232-2 6 99 January 1965 At 3 00 PM MST December 5 196' a retrorocket fired on a MINUTEMAN mlaaile at Site Lima Jt Ellaworth AFB South Dakota Tbla missile under the command of tbe 4 Stratepc Mia• ile Wiq was on atratelic alert and was fitted with a Mk 11 Be-entry Vebicle contain1D I a Mk 56 Mod 1 warhead The re-entry vehicle wu dl• lodpd and tell approximately '15 feet to tbe noor of the silo Tb1a report cover• tbe lDvelltipUOn conducted by AEC representatives at the accident • lte GROUP 1- EXCLUDED FROM AUTOIIAnc DODGRADING Al1D DECLASSIFICAnOR Tbls documents consists of 22 pages No SPE A - • ---- r j ' 'ff• J • I' • 31 of 44 copies Series A • - I I• i i -1 Thia report was prepared for distribution within Sandia Corporation and the external dlatribution shown No further external diatribution of this report or dissemination of the information contaiDed in the report shall be made without the approval of the issuing organization - _ - ' • J ONLY 1 --- - -·-·-------' CONTENTS Page Introduction 3 Investigating Parti es 3 Condition of WPapon 14 Recovery Operat ion 17 Security a nd Public Relations 21 Preliminary Post-Mortem Resul t s 21 Summary and Conclusions 21 i_ 4 • ILLUSTRATIONS FiE llre Page Re-entry Vehicle Attitude-Control Rockets 5 2 Abrasions on the First and Second-Stage Rocket Motors 6 3 Arming Firing and Attitude Control Assembly Top View 7 4 Arming Fi ring and Attitude Control Assemb y Bottom View 8 ArminJ Firing and Attitude Control Assembly Side View 9 l i Re-entry 'ehicle on Silo Floor 10 ' Evide nc e of Fired Retrorocket 12 B Aft End nf Re-entry Vehicle 13 Forward F nrl of Re- entry Vehicle 15 lU Step Jnint in Flare Section 16 lI Rt -f'ntr - '@hiclP Clearing Silo 18 12 Rt- -c-ntry Vehic-lC' During Transfer to Van 19 1 i Rt •-l' ntry Vehicle in Van 20 REPORT OF MINUTEMAN ACCIDENT INVOL G A MK 11 RE-ENTRY VEHICLE AT SITE LIMA II DECEMBER 5 1964 Introduction At 3 00 PM MST December 5 1964 a retrorocket fired on a MINUTEMAN missile at Site Lima II Ellsworth AFB South Dakota This missile under the command of the 44 Strategic MiHile Win was on strategic alert and was fitted with a Mk 11 Re-entry Vehicle RV containine a Mk 56 Mod 1 warhead The RV was dislodged and fell approximately 75 feet to the floor of the silo The miHile warhead and Arming Firing and Attitude Control components AF AC were in the safe condition at the time of the accident Investigating Parties Around 8 00 PM MST December 5 Mr D P Dickason ALO was notified by the Director of Nuclear Safety at Kirtland AFB that some squibs had fired on a MINUTEMAN missile and that a potential Broken Arrow had been declared Mr Dickason subsequently notified Lawrence Radiation Laboratory LRL and Sandia Corporation SC of the ituation By midnight it was till unclear lf any action by the laboratories was needed At 6 00 AM PST December 6 1964 Mr D M Olson Sandia Corporation Sandia Laboratory SCSL and Mr Dickason called Mr R K Petersen Sandia Corporation Livermore Laboratory SCLL and stated that the RV had fallen 7 5 feet to the silo floor They informed him that the Director or Nuclear Safety at Kirtland AFB was sending a team of observers to Ellsworth AFB and that AEC DMA wanted an ALO representative to accompany them It was decided that an SCLL representative should meet the team in Denver and proceed to Ellsworth AFB It was also decided at this time that an LRL representative probably was not required Mr M D Martin LRL who had been previously informel l of the situa tion was contacted and concurred He asked to be notified of the conditions at the silo and stated that he would then send someone if the situation warranted it The group of observers consisted of Mr D P Dickason AEC ALO Lt Col J 0 Mitchell TSAF DNS Ma j H B Lacy USAF DNS Capt D J Loosky USAF AI-'WL and Mr R K Petersen SCLL The group arriv e tl at Ellswort h AFB South Dakota at 3 45 PM MST December 6 1964 and went immediately to the office of Lt Col J W Eskridge Director of Safety 44 Strategic Missile Wing There the group was briefed as follows At 2 00 PM MST December 5 1964 two airmen entered Lima Il to investigate an IZ inner zone security alarm They opened the personnel access door and dee ended to the equipment room to conduct a routin e c hPck of the I Z and 3 - 0 Z outer zone security circuitry The check consisted in part of removing a fuse and observing the operation of a relay to determine continuity When the fuse had been removed and reinserted the thlrd time there was a violent explosion This explosion occurred at approximately 3 00 PM MST About one hour later the two airmen returned in the company of a third airman and after a cursory inspection through openings in the launch tube reported that the RV was missing The group of observers then reported to the Command Post and Col V M Cloyd Commander 44 Strategic Missile 1 lng Here they were able to monitor via remote hookup the progress of the explosive ordnance EOD team as it entered the silo at 5 00 PM MST The EOD team was to L Safe the 1gnitors on the mlssile 2 Disconnect the ignitor batteries at the J-Box 3 Safe and remove the RV attitude-control rockets which were still lying on top of the missile Figure l and 4 Inspect the RV at the bottom of the silo This waa the ftrat close look at the RV After completion of items 1 2 and 3 Capt M M Costa 2701 EOD Ellsworth AFB and Capt E S Tac hirhart OOAM A Hill AFB deacended to the bottom of the silo They reported l Some abrasions were present on the Hrst and second stage rockets Figure 2 2 Debris from the exit nose cone wae preaent at the m1eaile aupport ring Number 1 3 The firing set 11 was ly1 n1 on the floor 6 feet from the RV this was later identified as the AF AC Figures 3 4 and 5 4 '-Jo contamination was indicated by monitoring equipment and - The RV was damaged and lying partlally under one of the base l egs of thc- missile support ring Figure 6 Afte r completion of thi s operation the silo was secured ard the observers atl 1 ou 1·ned t'o1· the• day At A 00 AM Oec- mber 7 the observers met with Col J V Farley Malmstrom AFB and offered their services Col Farley was l'1·esident of the 15th Air Force Acci dent lnve tigation Board that had been formed t o inv •1 tigatc this acc i dent He invited the group to attend the briefing the EOD was about to p r rst-'nl i-11 SMW The EOD team leader Capt Tschirhart presented his group ' s obsen•ations with the a id of color slides ta ken during the inspection the previous night 4 J _ l · lfl · 11 11 I I · -I l d • • mcl - Sta 1· ltrwk1 · l l 11 · - $' rt- i·• · '· 'I _ I • I ••_ t -· - - t · 11111 I· ' IC 1 1 d ttitnrlt C' nt r• 1 •i l'llthl TOp Vt •W r • 1· L' ll -L ·minJ 1· 1· 11c i nd 1 I udl' '11 d r· i •m lily Hot 111111 i l'W ·- - ·5 - ·· I ·• -- 'M - - _ J ' •• _ i ·l-'il l1t·t• 5_ n11 ing F il· nJ a11d Attitud · Control 1 1 sl'ml ly i i • ' 1-' 1 u1 Capt Tschirhart reported that one rt troroeket had fireG Figure 7 a nd stated that thi s had caused the RV to separate and all to the bottom of the silo He reported that the firing set had broken looee and that the tritium bottle was exposed to view but seemed intact Further Capt Tschirhart was certain that the warhead high explosive HE had broken u DOE Deleted b 3 - - - - - - - - - - - - - - -- During this presentation a a ty s 1 e pro jector prevented the color slides from showing a clear picture of the situation Capt Tschirhart recommended removi n g the RV with modified RV handling quipment and then disassembling and d spoBing of it somewhere at Ellsworth AFB After the briefing Mr Martin and Mr N D Benedict of LRL were contacted By using an EOD manual at each end of the telephone conversation the following information wu relayed l The '' firing set'' had separated from the RV and was lying about 6 feet away 2 Some water containing a yellow aubstance perhaps sodium dichromate from the cooling system was on the floor of the silo 3 All monitoring equipment regiatered low readings 1 e background only 4 Avcoating and ablative material were shattered 5 6 7 Deleted DOE b 3 - The reservoir was intact Deleted 8 The sides of the case were not ruptured 9 The nose of the RV was off and the forward end of RV was caved in and split DOE b 3 10 Impact c1·ystals were visible and some had peeled away 1 l The warhead was visible through the RV shell 12 There was no apparent damage to the HE nuclear outer structure however the HE had probably fractured and 13 The missile showed abra• ive marks but no pun- tures It was apparent that items 1 5 6 and 7 did not correl ate It was also apparent to Mr Martin and Mr Benedict that item 12 might not be a good estimation of the situation Mr Benedict did not think that the HE had fractured but he felt other damage might have been done They asked if a better look at the slides could be obtained ll '- Figu rf' 7 Eddt-nc-C' of Fi r Pd Ret r·orockt-l l-' cun· 1- ·I - H _- • 11 · h 1 · ' • Another slide ro ·ector was located nd the slides reviewed _________________________________ Deleted __ DOE b 3 Mr Martin eubeequently requested that the RV not be moved until Mr Benedict arrived to assay the situation The request was relayed and the Air Force arreed to wait Mr Benedict arrived at 8 00 PM MST December 7 1964 He was briefed and was shown the slides of the RV The group of observers received permission to enter Lima n the next mornini to conduct a firet-hand investigation Condition of Weapon On Tuesday December 8 1964 the observers went down the silo at Lima II The following observations were made 1 The missile had some minor abrasions on the side of the second and first stages 2 The gas reservoir was intact but leaning to one side J 4 5 6 7 DOE Deleted b 3 The electrical component deck had moved forward l to 2 inches and was dented DOE D leted b 3 The outer portions of the firing set had been blackened and The nare was nattened with a major diameter of approximately 30 inches and a minor di eter of approximately 26 inches Mr Benedict decided that the only way to brin the unit up would be nose down in a car o net with the net stra ed to the unit __- --_ _ _ _ _ _ _ _ _ _ _ _ _ _ _Deleted _ _ ___ Any render-safe procedures wou ld be done at a magazine thereby minimizing personnel hazards The Accident Investigation Board met at 8 30 PM Mr Benedict briefed t hc m as follows regarding his opinion of the condition of the warhead 1 14 The step joint in the flare section had opened 30 to 50 mils either because of sheared rivets elongated holes or both Fi gure 10 DOE b 3 r DOE b 3 Deleted IIJegible 2 The warhead pit seal had probably not opened no alpha 3 The reservoir was intact and 4 DOE Deleted b 3 The Board was also informed that the warhead was electrically inert since the power supplies had been torn away and there was no reason to suspect that any residual electrical charges were present Recovery Operation Mr Benedict presented his plans for RV recovery to the Accident Investigation Board In conjunction with Mr Benedict's plan outlined previously Mr Petersen had recommended that the warhead should come up isolated electrically from the hoisting crane and other ground points since circulating ground currents in the area were undetermined The rocket engineers now became a larmed at the possibility of static discharge due to the cold dry climate and the nylon cargo net Mr Petersen then recommended a high-resistance grounding circuit and confirmed its adequacy with Mr J S Anderson SCLL ·rhe EOD built the dev ice for attachment to the RV and the Board approved its use SAC 15th Air Force BSD and others apprcwed t h e plan for removal of the RV on December 9 A mobile crane was positioned over the silo The RV was manually moved to a hoisting position and then raised slightly with the crane and a strap A heavy nylon cargo net was slipped under the RV and securely strapped to the unit The grounding cable and a safety rope were attached The RV was then hoisted out in a nose-down attitude and cleared the silo at approximately 4 50 PM MST December 9 1964 Figure 11 The RV was immediately transferred to an RV van where it was suspended from an overhead track-mounted hoist Figure 12 The nose was rested on matresses with the hoist used to maintain vertical alignment and cargo tie down s1raps used to prevent lateral motion FiiUre 13 The RV was moved from Lima II to Ellsworth AFB on December 10 Mr Benedict had requested radiographers a radiation safety specialist and their equipment from LRL Mr W T Fritts and Mr F F Sojka were the radiographers and Mr G E Costella was the radiation safety spec ialist The RV arrived at Ellsworth AFB at 4 30 PM December 10 and was taken to a magazin for the render-safe procedures At 9 00 PM the DT reservoir was removed and radiographs were taken to determine the condition of the internal parts The radiographs were reviewed n the early hours of December 11 and indicated DOE no cracked HE and no deformation of the it Deleted b 3 It was concluded that with some further disassembly and proper packaging the unit was safe for shipment to Medina 17 I -' •• 1' F I ' l •- •· 1 ·1 l I- - I • •• • o I • j • F in · 1 I • I n • 1 · 1 ·1 I Deleted DOE b 3 This was subsequently done by the EOD at Ellsworth AFB The group or observers except for Mr Benedict left Ellsworth AFB at 2 45 PM MST on December 11 Mr Benedict stayed to make arrangements for packing and shipping the unit to Medina Security and Public Relations Security and public relations were handled by the 44 Strategic Missile Wing and E lsworth AFB No release concerning this incident was made to the press The entire operation was handled in such a way that the nearby communities were not aware of and did not exhibit even a mild interest in the operation Preliminary Pcst-Mo ·tem Results At the time of this writing a post-mortem had not been conducted There is no reason to suspect that any of the warhead electrical components were actuated The wa rhead component deck will be shipped to SCLL from Medina for postmortem of components by the design group responsible - Summary and Conclusions This accident shows as do all others that circumstances make each accident unique The warhead had been de11igned to withstand and remain safe in all conceivable situations Even so after this accident the warhead was in such a condition that an improper recovery procedure could have had serious consequences U not actually leading to a detonation an improper procedure could perhaps have placed the nuclear system in a more critical state The Air Force never requested the assistance of the design agencies and was prepared to recover on its own The fact that the agencies responded of their own accord and were in fact utilized immediately points out that they were needed A recommendation as to how to prevent this type of acc ident cannot be madthe re but a recommendation is made that the AEC laboratories respond whether requested or not at the first indication of trouble The EOD teams seem competent en o ugh to handle most of the situations but in this instance as in others there are always those peculiar circumstances which should be viewed by persons intimately familiar with the weapon design I DISTRIBUTION l-15 44A - D P Dickason Storage Division ALO N D Benedict LRL l6 44A M D Martin LRL 17 44A S P Schwartz l 18 44A R W Henderson 1000 19 44A L A Hopkins Jr 1300 20 44A 21 44A - J H Findlay 1400 W A Gardner 1500 22 44A E H Draper 2000 23 44A H E Lenander 2500 24 44A D R Cotter 5500 25 44A L D Smith 5600 26 44A L E Lamkin 7300 21 44A A B Machen 7 500 28 44A B S Bigga 8000 29 44A L Gutierrez 8100 30 44A D E Gregeon 8141 3 1 44A C R Barncord 8150 32 44A L E Davies 8160 33 I 44A E F lngledue 8166 34 44A Technical Library 3f21 35 44A Central Technical File 3428-1 Attn Edna Baca Bldg 836 36 44A G C Newlin 6011 Central Technical File 3428-1 37 44A ln orrnation Distribution 3-427-3 38-39 44A E Bodie 8232-1 40 44A 41-44 44A Central Technical File 8232-2 This report was prepared for distribution within Sandia Corporation and the external distribution shown No furt her external distribution of this report or diS emt na1ion of the information contained in the report shall be made without the approval of the 1Huing organization '· __ _ 22