Thread by @Saturnax1

#SubWednesday #Submarines #Accidents #OTD
#Nuclear horror story, short🧵:
1. Soviet submarine K-320 was a Project 670 Skat/Charlie I-class SSGN. Designed by Lazurit design bureau, these submarines were intended to carry surprise attacks on Western/NATO high-value naval assets.

@CovertShores @Capt_Navy @RSS_40 @SubBrief @USN_Submariner @TayfunOzberk @FORONAVAL @The_Lookout_N @R_P_one @FPSchazly 2. Charlie-I SSGNs were armed with P-70 Ametist/SS-N-7 Starbright SLCMs housed in two rows of four missile tubes on each side of the bow & outside the pressure hull as well as 4x533mm & 2x400mm torpedo tubes capable to launch variety of torpedoes & decoys.

@CovertShores @Capt_Navy @RSS_40 @SubBrief @USN_Submariner @TayfunOzberk @FORONAVAL @The_Lookout_N @R_P_one @FPSchazly 3. K-320 was laid down at Krasnoe Sormovo Shipyard as K-302 on 30/04/1968, launched on 27/03/1971 & commissioned 15/09/1971.
At the beginning of 1970, the submarine was still on the slipway, when a serious radiological accident happened on 18 of January.

@CovertShores @Capt_Navy @RSS_40 @SubBrief @USN_Submariner @TayfunOzberk @FORONAVAL @The_Lookout_N @R_P_one @FPSchazly 4. K-302 was scheduled to be finished for Vladimir Lenin's 100th anniversary, thus the construction process was rushed. On Sunday 18/01 at 9:30 during hydraulic tests of the primary coolant circuit the reactor went prompt critical for ~10s due to violation of the test procedures.

@CovertShores @Capt_Navy @RSS_40 @SubBrief @USN_Submariner @TayfunOzberk @FORONAVAL @The_Lookout_N @R_P_one @FPSchazly 5. Temporary plugs of the primary circuit failed & radioactive fountain of contaminated water & steam shot 60m high, dousing everyone around & all the equipment including K-308 - another Charlie-I boat under construction. At the time of the accident there were 156 people present.

@CovertShores @Capt_Navy @RSS_40 @SubBrief @USN_Submariner @TayfunOzberk @FORONAVAL @The_Lookout_N @R_P_one @FPSchazly 6. The reactor vessel didn't explode after venting the excessive pressure through the failed primary coolant plugs. Total radioactivity released was ~75.000 Ci. As an immediate action all the people present at the shipyard were washed with cold water and later sent home.

@CovertShores @Capt_Navy @RSS_40 @SubBrief @USN_Submariner @TayfunOzberk @FORONAVAL @The_Lookout_N @R_P_one @FPSchazly 7. To meet the scheduled launch date (Vladimir Lenin's 100th anniversary), shipyard leadership, crew members & workers decided to quickly decontaminate K-302. From one group of 18 volunteers only 3 survived the clean-up due to poor equipment & hazardous procedures.

@CovertShores @Capt_Navy @RSS_40 @SubBrief @USN_Submariner @TayfunOzberk @FORONAVAL @The_Lookout_N @R_P_one @FPSchazly 8. Twelve workers near the reactor compartment died immediately during the accident. In total ~750 were involved in the clean-up activities and most suffered later on after being exposed to the radiation - some people were reportedly collecting radioactive dust with bare hands.

@CovertShores @Capt_Navy @RSS_40 @SubBrief @USN_Submariner @TayfunOzberk @FORONAVAL @The_Lookout_N @R_P_one @FPSchazly 9. After excessive clean-up of the shipyard & technology, the reactor compartment had to be replaced.
To meet the promised deadline, K-302 was renamed to K-320 with postponed commissioning & another Charlie I hull (yard №713) was named K-302 and commissioned on 01/12/1970.

@CovertShores @Capt_Navy @RSS_40 @SubBrief @USN_Submariner @TayfunOzberk @FORONAVAL @The_Lookout_N @R_P_one @FPSchazly 10. All Project 670 Skat/Charlie I & Project 670M Chayka/Charlie II-class SSGNs were finally decommissioned in the 90s and replaced by the Project 949 Granit/Oscar I & Project 949A Antey/Oscar II-class SSGNs with the latter still in active service.
End of🧵

@CovertShores @Capt_Navy @RSS_40 @SubBrief @USN_Submariner @TayfunOzberk @FORONAVAL @The_Lookout_N @R_P_one @FPSchazly FYI @Aviation_Intel @vcdgf555 @CislakJaroslaw @GrangerE04117 @KrastavacKonst1 @KaptainLOMA @militaryhistori @EmbersOfSuns @Aeroengineer1 @_LOAC_lawyer @Strike_Flanker @AlexLuck9 @ThingsNavy @IBallantyn @justapedn_cob @CollinSLKoh @KingNeptune767 @OSINTEng @NorthernFury94

@CovertShores @Capt_Navy @RSS_40 @SubBrief @USN_Submariner @TayfunOzberk @FORONAVAL @The_Lookout_N @R_P_one @FPSchazly @Aviation_Intel @vcdgf555 @CislakJaroslaw @GrangerE04117 @KrastavacKonst1 @KaptainLOMA @militaryhistori @EmbersOfSuns @Aeroengineer1 @_LOAC_lawyer @Strike_Flanker @AlexLuck9 @ThingsNavy @IBallantyn @justapedn_cob @CollinSLKoh @KingNeptune767 @OSINTEng @NorthernFury94 ICYMI my previous threads about nuclear accidents on Soviet Navy's submarines:

https://twitter.com/Saturnax1/status/1594092872198148096?s=20&t=cD3JUgGJBfyZLlS00w8WJQ

@CovertShores @Capt_Navy @RSS_40 @SubBrief @USN_Submariner @TayfunOzberk @FORONAVAL @The_Lookout_N @R_P_one @FPSchazly @Aviation_Intel @vcdgf555 @CislakJaroslaw @GrangerE04117 @KrastavacKonst1 @KaptainLOMA @militaryhistori @EmbersOfSuns @Aeroengineer1 @_LOAC_lawyer @Strike_Flanker @AlexLuck9 @ThingsNavy @IBallantyn @justapedn_cob @CollinSLKoh @KingNeptune767 @OSINTEng @NorthernFury94 + another one:

https://twitter.com/Saturnax1/status/1593358212589305856?s=20&t=cD3JUgGJBfyZLlS00w8WJQ