0018933 Notes on the’ developmental rocket firings and tests are outlined in Appendix A. Details of the firings on Koa and Walnut, which have been given in Sections 2,3,2 and 2.3.3, are not repeated. 2.3.6 Aircraft Samples, The B-57D aircraft used for the cloud sampling work were under the control of a LASL representative. The person responsible for these collections communicated with the aircraft by normal voice radio from the Air Operation Center on Site Fred, The fallout samples were taken by WB-50 aircraft controlled by an NRDL representative. They were directed from the Air Weather Central on Site Elmer using CW radio communication, The transmitters used by the Air Weather Central operated on a long wave length, thereby making it possible to maintain radio contact with the WB-50's at long ranges and low altitudes, ! Estimated coordinates for each sampling position on the height line flights were furnished by the Fallout Prediction Unit (FOPU). The initial 4 hour position prediction was based solely on the wind data available at shot time, but contacts made by the sampling aircraft, plus additional wind data, assisted in preparing the later estimates. Interchange of in- formation between FOPU and the Air Weather Central was mz2intained throughout the sampling flights, The FOPU predictions were generally quite accurate with respect to ;