Announced United States Nuclear Tests -- By Event Event Name Date (GCT) . Location Type Purpose. _ ; Yield Range .. Coulomb-C 12/09/57 NTS Surface Safety Experiment 0.5 kt Coulommiers 09/27/77 NTS Shaft WeaponsRelated 20 to 150 kt Coypu 04/10/63 NTS Shaft WeaponsRelated Low Cream Accidental release of radioactivity 12/16/70 NTS Shaft WeaponsRelated Less than 20 kt Crepe 12/05/64 NTS Shaft Weapons Related 20 to 200 kt Crew 11/04/68 NTS Shaft WeaponsRelated 20 to 200 kt Crewline 05/25/77 NTS Shaft WeaponsRelated 20 to 150 kt Crowdie 05/05/83 NTS Shaft WeaponsRelated Less than 20 kt Cruet 10/29/69 NTS Shaft WeaponsRelated 11 kt Cumarin 02/25/70 NTS Shaft WeaponsRelated 20 to 200 kt Cumberiand 04/11/63 NTS Shaft WeaponsRelated Low Cup 03/26/65 NTS Shaft WeaponsRelated 20 to 200 kt Cyathus 03/06/70 NTS Shaft WeaponsRelated 8.7 kt Cybar 07/17/86 NTS Shaft WeaponsRelated 20 to 150 kt Cyclamen Included heavy element experiment 05/05/66 NTS Shaft WeaponsRelated 12 kt Cypress 02/12/69 NTS Tunnel WeaponsEffects Less than 20 kt Dahthart 10/13/88 NTS Shaft WeaponsRelated Less than 150 kt Daiquiri 09/23/66 NTS Shaft WeaponsRelated Less than 20 kt Dakota 06/25/56 Bikini Barge Weapons Related Daman| 06/21/62 NTS Shaft WeaponsRelated Low Danablu 06/09/83 NTS Shaft Weapons Related Less than 20 kt detected on site only -67-