Extra. More complete details of the planning for this phase of the operation are included in ITF 132 SOP No, 76-4, dated 4 September 1952, as amended by SOP No. 76-4A,dated 18 October 1952, and need not be repeated here. The following outline indicates, in part, the results of that planning, including modifications made necessary by unforeseen conditions in the field. Flight Number 1E 2E 3E 4E 4EE Comments Asplanned, As planned, Program 4 samples not on board because of unavoidable delay in sample recovery; otherwise as planned. Departed Eniwetok, with first available Program 4 samples, at approximately H+68 hr. Program 5 samples not aboard because insufficient recovery time was allowed. AFOAT-1 samples on-loaded at Kwajalein as planned, but off-loaded at Travis and held for 4EE. Flight terminated, and Program 4 samples off-loaded at Kirtland. Departed Eniwetok, with bulk of Program 5 samples, at approximately H+115 hr. Carried tritium containers from Kwajalein to Kirtland. Picked up ‘AFOAT-1 samples at Travis as indicated above. Served effectively to soe 5E 6E 1E 8E 8EE clean up the bulk of Mike Shot sample-return requirements, Remainder of Mike Shot samples returned to ZI via regular MATSflights as required. ‘ As planned. As planned. Departed Eniwetok at approximately H+32 hr with first available samples for Program 4 and AFOAT-1. Picked up additional AFOAT-1 samples at Kwajalein. Program 4 samplesoff-loaded at Kirtland. AFOAT-1 samples off-loaded, and flight terminated at Logan. Departed Eniwetok at approximately H+48 hr with samples for Programs 4 and 5. Picked up AFOAT-1 samples at Kwajalein. Program 4 samples off-loaded at Kirtland, and Program 5 samples off-loaded at Friendship. AFOAT-1 samples off-loaded, and flight terminated at Logan. Departed Eniwetok at approximately H+56 hr with final group of Program 4 sampies. This flight was also utilized to return Program | instruments, the high priority of such a return being dictated by ZI test planning. Flight terminated, and load transferred to CARCO,for transport to Los Alamos, at Travis. Thus we see that the sample-return mission was accomplished. The chain of eventsfirst indicated by the lack of Program 4 samples on Flight 3E directed attention to several weaknesses in the plan outlined in the above-mentioned SOP’s that, it is hoped, can be avoided in future operations. A suggested solution to these weaknesses is discussed in Sec. 3.19. 3.11 RECOVERY OPERATIONS The recovery of experimental data, samples, and equipment after Mike and King Shots of Operation Ivy involved extensive coordination between experimenters, the intra-atoll transportation system, and the radiological-safety organization (TU 7). Each recovery team was accompanied by a TU 7 representative responsible for monitoring the radiation levels en- 35