Declassified photos show the US's final preparations for the only nuclear weapons attacks in history

On August 6th and 9th of 1945, the United States dropped atomic bombs over the Japanese cities of Hiroshima and Nagasaki, causing significant death and destruction in both places. To this day, the bombings remain history’s only acts of nuclear warfare.

A lot has been established about the immediate preparations for the dropping of the bombs, known as “Little Boy” and “Fat Man,” which were loaded onto aeroplanes on the North Field airbase on Tinian Island, part of the Northern Mariana Islands to the south of Japan.

Until recently few photographs were available of the final hours before the bombings. But newly declassified pictures shed additional light on the procedures leading up to the nuclear attacks, giving a chilling glimpse into how and where the most destructive bombs ever used in warfare were loaded.

(First seen on AlternativeWars.com)

Soldiers check the casings on the 'Fat Man' atomic bomb. Multiple test bombs were created on Tinian Island. All were roughly identical to an operational bomb, even though they lacked the necessary equipment to detonate.

National Archives

On the left, geophysicist and Manhattan Project participant Francis Birch marks the bomb unit that would become 'Little Boy' while Norman Ramsey, who would later win the Nobel Prize in Physics, looks on.

National Archives

A technician applies sealant and putty to the crevices of 'Fat Man,' a final preparation to make sure the environment inside the bomb would be stable enough to sustain a full impact once the bomb was detonated.

National Archives

Soldiers and workers sign their names and other messages on the nose of 'Fat Man.'

National Archives

Here's a closer look.

National Archives

'Fat Man' is loaded onto a transport trailer and given a final once-over.

National Archives

The bomb is then escorted to the nearby North Field airbase on Tinian, shrouded in tarp.

National Archives

At the airfield, 'Fat Man' is lined up over a pit specifically constructed for it, from which it is then loaded into the plane that dropped it over Nagasaki on August 9, 1945.

National Archives

The bomb and its trailer are lowered down into the pit using a hydraulic lift.

National Archives

Workers check 'Little Boy' one last time, keeping the tarp on for security reasons. They used a similar lowering procedure for 'Fat Man' three days later.

National Archives

Once 'Little Boy' is ready, the Enola Gay, a Boeing B-29 Superfortress bomber, is reversed and positioned over the trench.

National Archives

The tarp is removed and the bomb is readied for loading.

National Archives

Using the hydraulic lift, 'Little Boy' is carefully raised and loaded into the belly of the Enola Gay.

National Archives

Once inside the plane, the bomb is secured and all connections and equipment are checked again.

National Archives

Video of the preparation and loading also exists.

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