Even the airmen knew Deak Parsons to be the leader of a mixed group of officers, enlisted men, and civilians at the heart of the hush-hush mission on Tinian. But none among the aircrews except Tibbets knew that this naval officer in their midst was the ordnance chief and associate director of a secret weapons laboratory at Los Alamos, New Mexico, where the gadget had been designed and developed.
Parsons told the crews, "The bomb you are going to drop is something new in the history of warfare. It is the most destructive weapon ever produced. We think it will knock out everything within a three-mile area." He then signaled for a film of the weapon exploding from the top of a tower in New Mexico. When the projector began chewing up the film, Parsons had it stopped. With characteristic dryness he said, "The film you are now not about to see was made of the only test we performed."
Instead of showing the film of the Trinity test, Parsons described what he had seen less than three weeks earlier: "I was in a B-29 looking down at the flash in the darkness and I can say it is the brightest and hottest thing on this earth since creation." He described the churning mushroom and dust column that rose to the stratosphere. The combat version of that bomb was now assembled and ready, he said. All they were waiting for was the end of a rainstorm then raging over Japan. ...
That evening Parsons retired to his tent among those of the 50 civilians and officers he had brought from Los Alamos to direct the technical work of the mission. The tents were pitched alongside the four parallel runways of Tinian's North Field. The island had been captured ten months earlier. Rush construction had made it, in essence, a giant aircraft carrier. Bomb-laden B-29s now used it for mass air raids on Japan. One of these raids occurred the night after the briefing. Every 15 seconds for an hour and a half another B-29 would start down one of the runways, the four Wright 2,200-horsepower engines revved up to bring the plane to flying speed before the end of the runway. Of those from previous runs that had not made it, only burned hulls remained.
This night four bombers in a row crashed on takeoff.5 Parsons watched the night sky turn bright with flames fed by exploding ammunition and fuel for the 3,000-mile round trip. These accidents were tragic, but Parsons could envision far worse. The bomber on the nuclear mission would be 15,000 pounds overweight. If it crashed, fire could ignite the bomb's powder charge and propel the uranium235 bullet into a uranium-235 sleeve, creating some level of nuclear explosion.
Parsons was not a man to change an agreed-upon plan without good reason. He and General [Leslie] Groves had decided earlier that the bomb should be completely assembled before takeoff because of the difficulty of doing so in the cramped space of the plane's bomb bay. But that decision came before Parsons witnessed plane crashes that turned the early morning bright with flame.
Shortly after sunup on Sunday, 5 August, Parsons shared his concerns with Brigadier General Thomas Farrell, Groves' deputy at Tinian. Parsons warned that if the overloaded bombing plane crashed on takeoff, "we'd make a terrible mess of things around here."
To avoid such a risk, Parsons advocated that he load the powder charges to the Little Boy gun after the plane took off and was clear of the island. Farrell, aware of Groves' opposition to in-flight tinkering, asked whether Parsons had made the assembly with the powder charges before. "No," Parsons responded, "but I've got all day to try it."
By 1500 the 9,700-pound bomb, 10.5 feet long and 29 inches in diameter, hung from its hook in the bomb bay of the Enola Gay , sway braces attached. Parsons crawled into the bomb bay, squeezing himself into the narrow space at the tail of this weapon so innocuously named Little Boy. He held a checklist covering the steps for loading the high explosives and the detonator for triggering the nuclear explosion. Perched on a narrow catwalk hastily constructed that morning, he endured the sweltering heat, cramped quarters, and poor lighting within the bomb bay. Time and time again he repeated the 11 steps on the list.
When General Farrell dropped by, he noticed that Parsons' graphite-blackened hands were nicked from working with sharp-edged parts within the bomb. "For God's sake, man," Farrell urged, "let me loan you a pair of pigskin gloves."
"I wouldn't dare," Parsons replied. "I've got to feel the touch." . . .
Parsons proclaimed himself a sailor at heart, but it was the allure of science that took control of his career and set him on a nuclear odyssey. During World War II this odyssey took him to Los Alamos, Trinity, Tinian, and—as bomb commander—the Hiroshima mission of the Enola Gay . After the war it would take him to Operation Crossroads and the nuclear tests at Eniwetok. As the Atomic Admiral of the postwar world, he led the Navy into the nuclear age." He did more than any other officer of his time to shape the Navy's nuclear policies and capabilities. He was an early advocate of nuclear power for ships and submarines, and his initiatives gave nuclear strike capabilities to carrier aircraft. As the military's foremost nuclear expert, he provided technical leadership for, and witnessed, seven of the first eight atomic explosions.
Parsons' achievements and influence went beyond the nuclear. As a lieutenant in the early 1930s, he had been the first officer of any service to recognize the full military potential of high-frequency radio experiments at the Naval Research Laboratory. These were the beginnings of radar.
Early in World War II, Parsons provided military leadership in the creation of the proximity fuse, essentially a miniature radar installed in projectiles so that they can sense when they are within lethal distance of their target. As with the atomic bomb, he accompanied the proximity fuse during its first use in combat. . . .
Deak Parsons' naval career spanned the years 1918 to 1953, a full cycle from post-World War I to post-World War II. During that time the relationship between U.S. science and the military changed from indifference to collaboration. The result was a weapons revolution that perfected radar and created the first mass-produced smart weapons, modern military rockets, guided missiles, and the atomic bomb. Parsons played active roles, both military and technical, in these major advances. His is a life that reveals both lessons and cautions concerning the use of science for military purposes. It is the life of a new kind of warrior.
Mr. Christman , a retired Air Force Reserve major, has researched Parsons since 1965. He is the author of the upcoming Naval Institute Press book, Target Hiroshima: Deak Parsons and the Creation of the Atomic Bomb .