Truman ordered the bomb dropped on two Japanese cities. His decision created a controversy that is with us today. On August 6,the world changed forever. About 70, persons, some military but mostly civilian, perished in the blast and the firestorm that resulted from it.
Height of Detonation A. The criteria for determining height selection were discussed. It was agreed that fuses should be prepared to meet the following possibilities: With present knowledge the fuse setting corresponding to 5, tons equivalent would be used but fusing for the other should be available in case more is known at the time of delivery.
The height of detonation corresponding to 5, and 15, tons are feet and feet, respectively. With the present information the fuse should be set at 2, tons equivalent but fusing for the other values should be available at the time of final delivery.
The heights of detonation corresponding to2, and 5, tons are feet, 1, feet and 1, feet, respectively. Trinity data will be used for this gadget.
In the case of the Fat Man delay circuits are introduced into the unit for purposes which make the detonation of the bomb feet below the height at which the fuse is set. For this reason as far as the Fat Man is concerned the fuse settings should be feet, 1, feet, or 1, feet.
In view of the above it was agreed by all present that fuses should be available at four 4 different height settings. These heights are 1, feet, 1, feet, 2, feet and 2, feet. With present information the 1, feet fuse would be most likely to be used for both the Fat Man and the Little Boy.
Later data presented by Dr. Brode modify the above conclusions on fusing and detonating heights; the differential height for the Little Boy is feet and for the Fat Man feet. For this reason some of the above figures must be revised. Report on Weather and Operations A.
Dennison reported on the above subject. His report essentially covered the materials in his Top Secret memo of 9 May - Subject: It was agreed by those present that the mission if at all possible should be a visual bombing mission. For this we should be prepared to wait until there is a good weather forecast in one or more of three alternative targets.
When the mission does take place there should be weather spotter aircraft over each of three alternative targets in order that an alternative target may be selected in the last hour of the flight if the weather is unpromising over the highest priority target.
In case the aircraft reaches the target and finds, despite these precautions that visual bombing is impossible, it should return to its base provided that it is in good operating condition.
Only if the aircraft is in sufficiently bad shape that it is unlikely that it can return to base and make a safe landing or if it is essential that the drop be made that day should the drop be made with radar equipment.
For this purpose it may be desirable to have an Eagle radar equipped plane accompany the mission in order that formation bombing with the Eagle plane in the lead can be made to obtain the increased accuracy from Eagle.
A final decision as to the desirablity of this emergency procedure can only be made after further combat experience is obtained with Eagle aircraft. In any case every effort should be made to have the mission such that blind bombing will be unnecessary.
It was agreed that Dr. Dennison should keep themselves continuously informed as to radar developments. If at any time new developments are available which show in combat a marked improvement of accuracy the basic plan may be altered. It was agreed that Shoran was a very promising development for the 21st Bomber Command but that we should make no plans to use Shoran until its success is fully confirmed in normal bombing missions in that area.
The plan to use the gadget with visual bombing even though this may require a one day to three weeks delay requires that the gadget be such that for a period of at least three weeks it can be held in readiness in such a state that on twelve hours notice it can be prepared for a combat mission.
No difficulty in this regard was foreseen by those present. Gadget Jettisoning and Landing A. It was agreed that if the aircraft has to return to its base with the gadget and if it is in good condition when it has reached there, it should make a normal landing with the greatest possible care and with such precautions as stand-by fire equipment being held in readiness on the ground.
This operation will inevitably involve some risks to the base and to the other aircraft parked on the field. However, the chance of a crash when the aircraft is in good condition and the chances of a crash initiating a high order explosion are both sufficiently small that it was the view of those present that the landing operation with the unit under these circumstances was a justifiable risk.
Frequent landings with inert and H.WEB SITES ON RELATED TOPICS: The Leo Szilard page (The Manhattan Project and the atomic bombings).. Chronology on the Decision to Bomb Hiroshima and Nagasaki (by the Nuclear Age Peace Foundation)..
The Hiroshima Archive.. Chronological History of Nuclear Weapons. The Story of Hiroshima Hibakusha Stories. First-hand accounts from survivors best convey the bomb’s impact on Hiroshima’s people.
The following "Voice of Hibakusha" eyewitness accounts of the bombing of Hiroshima are from the program HIROSHIMA WITNESS produced by the Hiroshima Peace Cultural Center and NHK, the public broadcasting company of Japan.
In just one second, in early August, , the world was changed forever. Since , a secret U.S. weapons program, called the Manhattan Project, had been at work on two revolutionary bombs of such intense heat and explosive force that they would reduce the two target cities—Hiroshima and Nagasaki—to vast scorched wastelands.
world. On this day a single bomb dropped by a single airplane destroyed the city, leading to the end of World War II and introducing mankind to the Atomic Age. Dr. Michihiko Hachiya lived through that day and kept a diary of his experience. He served as Director of the Hiroshima Communications.
Minutes of the second meeting of the Target Committee Los Alamos, May , Source: U.S.
National Archives, Record Group 77, Records of the Office of the Chief of Engineers, Manhattan Engineer District, TS Manhattan Project File ''46, folder 5D Selection of Targets, 2 Notes on Target Committee Meetings. An image of the first page of this document is included below the transcription.
Was it right to bomb Hiroshima? One argument supporting the case that dropping the nuclear bomb was the right thing to do, is that the immediate deaths that it caused are outweighed by lives.