Hours away from stunning the world with the explosive power of a splitting atom, the Little Boy atom bomb lies motionless on a trailer cradle, in this photo that was produced on the 5th of August in 1945.
The atom bomb was just about to be lifted into the bomb bay of a B-29 Super Fortress nicknamed as the Enola Gay, at the North Field airbase on Tinian island. Its name was inspired by Harry Truman, and was in essence a code name coined by U.S. air force pilots assigned to the mission.
Little Boy atom bomb.
The Little Boy was a uranium based atom bomb and the first of the two atom bombs to be used in 1945. It was a cigar-shaped bomb, 10 feet long and 28 inches in diameter. It was also the only one to be produced out of uranium 235. An isotope so rare and hard to separate from the more abundant isotope of 238, that if a second of its type was needed, it would have taken several more months to put together.
The bomb was created at the Los Alamos Laboratory in New Mexico and was the brainchild of American geophysicist Francis Birch. It was developed after its predecessor, the plutonium-based Thin Man was scrapped for developing a fatal incompatibility.
Designed as a gun-type fission device, it was pre-configured to fire through a uranium barrel, a hollow uranium bullet of subcritical mass into a uranium target of subcritical mass to produce the chain reaction required for the atomic explosion.
The bomb was almost completely made out of isotope 235 and had weighed some 9,700 pounds. Inside its uranium casing, it had packed an explosive firepower equivalent to 15,000 TNT.
How the uranium for the Little Boy atom bomb was procured.
As uranium ore at the time was a rare resource and not in stockpile in the U.S., the bomb was produced in stages as and when the metal was available for refinement and use.
The first 1,200 pounds that had gone into its making had come from the Shinkolobwe Mines located in the Katanga province of the Republic of Congo in Africa. The Katanga province was then a Belgian colony with the mine owned by a Belgian mining company known as the Union Minière du Haut-Katanga.
The second 1,200 pounds, was procured from a German installation in Germany. The third, 1,000 pounds had come from a captured German submarine that was headed for Japan with the rare metal (and advanced weapon technology) in May, 1945.
When the Little Boy atom bomb was manufactured.
The bomb was manufactured in the month of June in 1945 with its components produced in different installation plants across the U.S. It had then been transported in parts to the North Field airbase on Tinian island to be assembled by technicians.
While the USS heavy cruiser Indianapolis had ferried the bulk and essential components of the bomb to the island by sea, C-54 Skymasters had flown its uranium projectile and target.
On Tinian, the bomb was assembled by trained technicians of Project Alberta, under the supervision of physicist Francis Birch and Norman Ramsey.
Project Alberta was a part of the Manhattan Project – a colossal undertaking of military divisions, universities and eminent scientists tasked with researching and developing the atom bombs.
It was originally a small experiment funded by U.S. President Roosevelt at the onset of World War II in 1939. It had, however, burgeoned overnight into a massive secret project, after the Japanese attack on Pearl Harbour, on the 7th of December in 1941.
Release over Hiroshima.
The Little Boy was deployed over Hiroshima by the B-29 Super Fortress bomber Enola Gay, on the 6th of August in 1945 at 8:15 Japanese Standard Time.
The bomb was released from a height of 31,000 feet and had detonated after a pre-configured delay of 43 seconds over its designated target – the T-shaped Aioia Bridge spanning the Ota River.
On detonation, the bomb had generated a heat of around 2,99,726 degrees celsius in the air, and 5,726 degrees celsius on the ground.
The blast and the ensuing firestorm had resulted in the incineration of those nearest to the epicenter.
An estimated 80, 000 people are believed to have perished at the time of the detonation. While 4.7 square miles of Hiroshima was razed with 48,000 buildings completely demolished.
In later months radiation poisoning and cancer would claim more lives, taking the number of deaths to140,000 people.
Little Boy, a flawed atom bomb.
Despite the wide-scale death and destruction, the bomb was later declared as a flawed weapon. Out of the 140 pounds of uranium fuel it contained, only 1.38% actually fissioned, proving it was not as destructive as it was created to be.
Moreover, it had also failed to accomplish its intended purpose -and which was the immediate surrender of Japan.
Covert Mission.
In 1945, the volatile weapon had also posed a great danger to the crew of the B-29 Super Fortress, Enola Gay – the bomber that had delivered the bomb to its target in Japan(see Farbound.Net story: Harbinger of the nuclear age),escorted by six other bombers of its type.
Owing to the covert nature of the mission, the handpicked crewmen were kept in the dark – till their last-minute debriefing on the 5th of August in 1945. The only person acquainted with its destructive power was Lieutenant Colonel Paul Tibbets, commander of the 509th Corps and pilot of the Enola Gay.
A 29-year-old decorated veteran and a bomber captain with a fine record of having released over 200 bombs over enemy-held territory in Europe and Africa, Tibbets was skeptical of its potential till he had witnessed the destruction below with his own eyes.
Photo.
This photo that shows the Little Boy atom bomb just beneath the bomb-bay of the Enola Gay with a door of the hold visible, is now catalogued by theNational Archives and Records Administration (NARA).
The photo may have been produced by a technician of Project Alberta or a photographer assigned by the U.S. War Department to document the event.
A division of the Manhattan Project, the technicians of Project Alberta had comprised of military and civilian personnel. The division was tasked with the transportation and onsite assembly of the atom bombs on Tinian island.
They had assembled both the uranium Little Boy and the plutonium Fat Man, see the Farbound.Net story: The bomb had ended World War II.
I F I This is an independent story highlighting this featured Vintage photo of the uranium Little Boy atom bomb from 1945. The story also sheds light on the specifications of the Little Boy atom bomb and when it was dropped over Hiroshima. It has been created from facts curated from literary sources and historical documents. I
