Net 5. Meanwhile, we had requested Dr. Bradbury and Dr, York to review the AFOAT-1 study of the high altitude shot. Dr. York's reply of May 8, 1956, (AEC 12/10) indicated that the problem was quite complicated, and there was not enough time for his laboratory to study the problem adequately during Operation REDWING, However, Dr, York did indicate that there is a possl- bility of formation of an acoustic signal through heating of the atmosphere by X-ray radiation from the bomb case, a phenomenon not considered by AFOAT~1, Dr. Bradbury, in his reply of May 8, 1956, (AEC 12/10) is in general agreement with AFOAT-1 in that our standard means of detection would encounter new problems in obtaining signals from an explosion of given size a8 burst . height is increased, However, he was highly mistrustful of the quantitative results of the AFOAT=1 analysis, He pointed out that LASL was not in a position to provide estimates without a formidable amount of theoretical work, Dr, Bradbury concluded that the difficulties facing any country conducting an atomic weapon development program, but utilizing only very high altitude tests would be stupendous, probably to the point of impracticability. 6, During my recent trip to the Pacific Proving Grounds I explored with Admiral Hanlon, Dr. Ogle and others the possibility of adding this very high altitude shot to Operation REDWING « JTF~7 can accommodate the shot operationally and requested that the target date be set at July 15, 1956, However scien~ tific personnel were extremely pessimistic over the data

Select target paragraph3