oe Qel SUIMARY OF SXPZRIDENPAL PRCGHUIS 2.1 TASK UNIT 3, OD PROGR 3 (T~3) 2.1.1 PROGRAM 1, RLAST AND SHCCK (EASUiE2..7S An accurate knowledge of free-field tlast and shock phcenomen’. is one of the essential ingredients needed by the DOD in «volving offencive and deten— sive strategy and in designing cefensive structurces and equipment. HawtTack Program 1 Projects were aimed at cxtencin. }nowledre of air blest and ground shock Phenomena pained in previous op -~et.one 4.9 Adchor pressures, larger yields, and a different soil type. In icdi'jon, slact and snock studies on H:.RDTACK were aimed at producing inform *+ic. from several shcet environments for which little or ne data was previousiy .vailable. 1, Blast and shock phenomens fram ondorwoter chots. 2. Characteristics of 4 blast usve fro. + 90,000 feet. Ground Shock, . burat at an altitude of -bout The entire OCD effort cr stucv of ground shock phenomena was concentrated on two surface shots, Tactun «nd Koa, Gcmplete air tlast lines were installed on these shots also so th t the civ blast input contributing to underzround effects would be incrm. chet Cactus wns chosen to provide a low yicld tie-in of underground date -i-r Plumbbob at NTS. .inilar data obtained on Operation Shot Koa was instrurentei se tact com wrisons (Cactus vs Koa) could be made between data from Low aad high yield shots under similar soil conditions, All five projects particip ting on Shots Cactus and Koa cuccessfully obtzined the larger part cf desired data. HKesults of individuel projects are summarized below, Airblast. Uf Complete air blast data were ottained on both shots. Overpres- sures ranged from 3%43 psi at 470 feet to 1.85 posi at 7868 foot zround range , CoysCpe Lane, go > PGE 7