CHRONOLOGY 4 March 1957 Joint Tak Force SiViN conference on Support Requirements for Operation HARDTACK, 29 April 1957 Issuance of message constituting author ity for initial planning for Operation HARDTACK, iL Cetober 1:57 3 Uctober 1957 1l Uctober 1957 29-30 Cctober 1957 Crganization of [ask uroup 7.4. assignment of Colonel silliam B, «ieffer as Commander of Task Group 7.4. Final book message issued by United ulates wir Force, Loxistics Pianning vonference held at dirtland «ir Force sase, ew nexico,. Planning Virective was published. 9 January 1958 wovement Jirective was published by United States dir Force. 6 February 1958 First echelon of fask Group 7.4 arrived at tniwetok. 19 February i958 Operation Plan 1-58 was published. li murch 1958 voening of Task Group 7.4 abt snuiwetok, 14 March 1958 cperational viiase of dsaKDTACK began. ~l napeh 1958 Series of sAWT.cn renearsals was be,un. é a) Cosa L958 N be 1957 Mee 29 wovember alr operivions center oecane fully ojer ition. YUC.. oubonited from . widenir Locaiticn. AFWL/ HQ