Atomic Veterans History Project Featured Photo Climax was the eleventh, and final, shot of the Upshot-Knothole series of atomic detonations conducted between March and May of 1953. To this date it was the largest device exploded at the Nevada Test Site. Click on photo for higher resolution picture. Climax Shot, 61 Kilotons Atomic Energy Commission Meeting No. 863 10:30 am., Monday May 18, 1953 1. AEC 487/55- Proposed Additional Shot for Upshot-Knothole Series General Fields discussed witth the Commissioners the basis for the proposal that an additional shot be inclided in the USHOT-KNOTHOLE series. He described the device to be tested and he and Mr. Graves commented on the significance of this test for future operations and for the progran of weapon development. Since no similar device had ever been tested, estimates of the yield were somewhat uncertain; however, yield would probably be (DELETED). Mr Dean said he was concerned that so large a detonation might produce serious shock in nearby communities or that it might cause severe fall-out or rain-out on more distant localities. Mr. Graves said that since this would be the last test of the series, it would be possible to select the weather conditions with great care. By this means severe shock damage and excessive fall-out could be avoided. He pointed out, moreover, that this test called for an airplane drop and a detonation at 1,000 to 1,300 feet, not a tower shot, and this would be a significant factor in keeping fall-out to a minimum. Mr. Dean asked whether it was considered necessary to make a public announcement concerning the unusually hish yield of the device to be tested. Mr. Graves and General Fields said that they considered it unnecessary to go beyond the information contained in the draft press release on this subject. Mr. Graves pointed out that the greater power of this device would probably not be noticed by persons in nearby communities. The Commissioners indicated that their approval of the additional test would be based on the assumption that the greatest care would be taken to mimize the effects of the detonation. AEC Meeting No. 866 11: a.m., Friday, May 22, 1953 J. Proposed Eleventh Shot Mr. Zuckert said that the recent fallout incident at St. George, Utah, coupled with claims of livestock deaths and concern about the effects of atomic tests on weather, made him fear the effect of testing a device at Nevada considerabley larger than any previously fired there. (Mr. Smyth) too, was concerned about the public relations aspect of the tests, especially in view of the St. George, incident and the large number of shots already fired. Mr. Zuckert said that the AEC was involving the President in this matter by the request for Presidential approval of expenditure of the additional fissionable material, but pointed out that the letter of request did not inform him of the magnitude of the shot or the possible dangers invoved. He felt, therefore, that Mr. Strauss should be promptly informed of the estimated yield of the proposed shot, the safety and public relations aspects involved, the need for an early test, and the alternatives to conducting the test at the Nevada Site. Dean Diary May 27, 1953 Presidential approval for 11th shot given today. Dean called Salisbury and stated that in meeting this morning the President expressed some concern, not too serious, but made the suggestion that we leave "thermonuclear" out of press releases and speeches. Also "fusion" and "hydrogen". The President says "keep them confused as to 'fission' and 'fusion'. Philip Fradkin wrote in his book Fallout, "In his second term Eisenhower became worried about the health effects of global fallout. This concern led to his declaring a moratorium on tests in 1958 over the vehement protests of Strauss." (AEC). --Keith Whittle December 6, 1997 Featured Photos Index [ Atomic Tests || Notes and Hints || Family Mail Call || Home Page || Email ]