THE DROPPING OF THE FIRST ATOMIC BOMB ON HIROSHIMA.
A Green safety plug and a red arming plug from L-11, "Little Boy", the First Atomic Bomb dropped on Japan.. Each plug made of composite metal and wood, 3 inches long and 1 inch in diameter, each housed in a custom shadow box with original annotated inspection tags mounted on the reverse. The label for the red plug an inspection card for L-11 signed and dated 7/31/45, and the card for the green plug a written statement signed by both Doll ans Jeppson. With a copy of a Statement of Authenticity produced by Morris R. Jeppson on June 11, 2002, at the time he offered his identical set of plugs at auction through Butterfields Auctioneers in San Francisco (a forerunner of American branch of Bonhams).
Provenance: Lieutenant Morris Jeppson (Weapons Test Officer on the flight of the Enola Gay); Gift to Dr. Edward B. Doll (Head of Fusing Team) on August 7, 1945; by descent through the family of Edward B. Doll.
ONE OF ONLY THREE SURVIVING SETS OF BOMB PLUGS, THE ONLY SURVIVING RELICS OF "LITTLE BOY," THE FIRST ATOMIC BOMB DETONATED OVER HIROSHIMA.. This set was given by Weapons Test Officer Jeppson to his superior Edward Doll, the day after the flight. Jeppson's own set was sold in Butterfields Auctions in 2002, now privately owned, and there is a further set in the Naval Museum Washington D.C., a set that belonged to Deak Parsons, who also flew on the Enola Gay as Senior Military Technical Observer. This last set is presumed to have been given to Parsons by Jeppson.
The race to develop nuclear weapons during World War II successfully culminated in the development of two types of bomb, Little Boy, dropped over Hiroshima on August 6, 1945, and "Fat Man" dropped over Nagasaki a few days later. 2nd Lieutenant Morris Jeppson was one of two men responsible for arming the atomic bomb "Little Boy", L-11, aboard the Enola Gay's flight from Tinian to Japan. He was a Yale, Harvard, and MIT-educated electrical engineer assigned to work on bombing missions with the Los Alamos scientists. His civilian boss was Edward B. Doll, the leader of the Fusing Team on Project Alberta, the group tasked with designing the bomb itself and its delivery over the target.
In a Statement of Authenticity produced by Jeppson when he sold his own set of plugs at auction in 2002, he explains the challenges facing the Project Alberta team: "Before this time, bombs dropped from aircraft detonated by striking the ground. Atomic bombs with 30,000 times the explosive power had to be detonated in the air at heights proportional to the size of the explosion. Los Alamos scientists recognized that an atomic explosion from a bomb dropped from low altitude would destroy the B-29. Therefore the plane should fly at a high altitude. As a result, the bomb designers faced several new problems: 1) How to detonate the bombs at 1500 feet above the ground while it is falling at 1000 feet per second. The answer had to be by radar directed between bomb and ground to electronically detect height. Four small radars were designed into the Hiroshima bomb; 2) To make sure that the bomb could not detonate too soon after leaving the plane, timing clocks isolated the firing voltage from the bomb detonator; 3) The concern that radars in the bomb, if turned on too soon, might pick up radiations from Japanese radar to cause premature firing too high above ground."
The plugs, roughly the shape of a car cigarette lighter, had distinct functions which were integral to the mission: the green safety plug prevented a premature detonation during transport and flight, while the red arming plug completed the electrical connections of the internal battery and the firing mechanism so that the bomb could be detonated by radar once it was dropped over the target.
Lt. Jeppson was the weapons test officer aboard the Enola Gay responsible for arming the bomb's fusing mechanism during flight. He describes that task in his 2002 statement: "Before the 'Enola Gay' moved to bombing altitude, my last responsibility was to climb into the bomb bay and remove three green electrical plugs that had enabled testing of the bomb fusing, and replace them with red-coded plugs. This allowed a detonation voltage to go from fusing to the explosive that fired a projectile of U235 into a target of U235—when the bomb reached a point about 1500 feet above Hiroshima...."
It was Dr. Edward Doll who suggested that Morris Jeppson save the bomb plugs as souvenirs of their mission. The day after the fateful flight, Doll wrote on the reverse of the inspection tag for the green plug: "7 August, 1945 / Tinian Island / I certify that this is one of the three green safety plugs used on L-11 at Hiroshima, Japan. This was the first atomic bomb used in the history of mankind. EB Doll." Jeppson also signed below Doll's signature. The red arming plug, obviously a spare not used in the detonation of the bomb, has its original Inspection Record and Assignment Record tag filled out in Jeppson's hand and initialed by Doll and which confirms what we know: that L-11 was assembled and ready for use by July 31, 1945.