a () Shen ) TASK GROVe 7.1 JOINT ASKD FORCE 7 411433 Los Alamos, New Mexico S February 1953 APPENDIX I to CLOUD SAMPLING BCUIREMENTSFOR CASTLE (u) 1. Introduction The collection of samles of airborne radioactive debris from the cloud resulting fron ths explosion of a test weapon or nuclear device is of the greatest value to the wagpons development program. ‘These samples susport critical radiochemical measurements which provide an absolute determination of the yield or energy release of the weapons is one of ite most important characteristics. In order to permit timely action for their support, the following requirements for manned aircraft to accomplish cloud sampling on CASTLE are submitted. these requirements are based largely upon IVY clow sampling experience and results. They are supported by the fact that the amount of radioactive material collected by ea sampling aircraft is quantitatively and directly pro~ portional to the performance of the filter device used, to the speed performance of the aircraft, to the radiation exposure of the sampling personnel, and to the extent of radioactive decay which hes occurred after burst by the time sampling is performed. The largest possible sample for a fixed biologically acceptable radiation exposure will be obtained by use of the highest possible performance filter device, and a high perforzance aircraft which samples as long as possible after burst as is consistent with cloud dispersal phenonmena. As a result of IVY and Nevada test experience, it is possible to state the sample sizes required for the CASTLE devices in terms of the radiation exposures and equipment per- formance used in the past. Further reduction of IVY data and development of oper- ational concepte may modify, to some extent, the requirements submitted herein. 2. Sanple Requirements a. Number Six primary samples are desired of each of the six devices tested. One special sample at highest possible altitude is desired, in addition to the primary six, for at least four of the aix devices. BEST COPY AVAILABLE b, Sise The size of each primary sarzle will be satisfactory when each re- presents the amount of material collected on seven to eight square feet of special filter paper by filter. devices which have a performance equivalent to the Fletcher wing tip type used on IVY, when the sampling pilot exposure on landing is 3.5 ARTMENT [ | ENERGY LASSIFICATION eini D CUesSHIE TEE21-97. |SCLAS IND MEVIity;EWDA ADO 9a, C1 to Admini REVIEW (CIRCLE NUMBER(S}] DETERMIMATION D-ofIFICATION RETAINED TO:<7 TST REVIEW-DATE: £2 CAGD JI CLASS CHANGED TION cLassiFICA AUTHORITY; CONTAINS.HoDoe: CLAS é NAM6: CADRDINA : canion CANCELED t ele ¥ , OTHER HHO BRACKETED ba] wry: Sanitized by NN-523 on 2]5/4°