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The mission that changed the world

On August 6, 1945, the crew of the Enola Gay dropped an atomic bomb designed at Los Alamos on the Japanese city of Hiroshima. As pilot Paul Tibbets Jr. and others explain, delivering a 10,000-pound bomb to southern Japan was a years-long endeavor that required patience, practice, and precision.
July 6, 2020
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Pilot Paul Tibbets Jr. named his B-29 bomber the “Enola Gay” after his mother, who long supported his dream of becoming a pilot.CREDIT: Los Alamos National Laboratory

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"Colonel, we wouldn’t be playing with atoms today, would we?”- Bob Caron

By Brye Steeves

Hours before the sun would rise over Tinian island on the morning of August 6, 1945, a B-29 airplane was positioned above a specially built bomb-loading pit, as crews readied the aircraft with cargo unlike anything the world had ever known.

Preparations on the tiny Pacific island—about 1,500 miles southeast of the plane’s intended target in Japan—had begun months before on April 3. And months before that, pilot Paul Tibbets Jr. and his crew had practiced dropping dummy concrete bombs on targets in Wendover, Utah. Even years before that, development of this revolutionary cargo began in secrecy under the direction of a physicist and an Army general in the mountains of Northern New Mexico.

It was all leading to one day that would help end years of bloodshed and change the world forever.

In the early-morning darkness of that historic day 75 years ago, Colonel Tibbets and his 11-man crew boarded the plane and began their preflight preparations. As the plane’s engines roared and its propellers spun, Tibbets looked out an open window at the crowd amassed on the runway. Sticking his head out just above the plane’s painted name— Enola Gay, after his mother—the 30-year-old husband and father gave a wave and a slight smile and began to taxi.

At 2:45 a.m., the plane took off, and at 8:15 a.m., the crew of the Enola Gay released Little Boy, the world’s first nuclear weapon, over the city of Hiroshima, Japan.

“I had to go fly airplanes”

About a year earlier, in September 1944, Tibbets was chosen to lead the mission to deliver the world’s first atomic bomb used in combat. But the man who would fly perhaps the world’s most important sortie almost wasn’t a pilot.

Tibbets was born to Paul and Enola Gay Tibbets on February 23, 1915, in Quincy, Illinois, and spent most of his childhood in Miami, Florida. He was drawn to flying at an early age, never forgetting a summer day at the local racetrack. A stunt pilot let a 12-year-old Tibbets climb aboard his small plane and toss Baby Ruth candy bars to the crowd below, according to The New York Times.

Tibbets later attended a private military preparatory school in Illinois and began taking flying lessons, despite his father’s wish for him to pursue a medical career. His mother, though, encouraged her son to follow his dream.

“He [my father] said, ‘You’re going to be a doctor,’ and I just nodded my head and that was it. And I started out that way. But about a year before, I was able to get into an airplane, fly it—I soloed—and I knew then that I had to go fly airplanes,” Tibbets said, according to a 2002 interview in The Guardian.

In 1937, Tibbets withdrew from the University of Cincinnati’s medical school and joined the U.S. Army Air Corps (which became the U.S. Air Force in 1947).


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Paul Tibbets Jr.

Training for a secret mission

Tibbets piloted various observation aircraft and bombers, including the B-17, which he flew in bombing raids above German-occupied Europe in the summer of 1942. By mid-1943, Tibbets began flying a new, innovative bomber: the B-29.

The aircraft would prove a game changer for the U.S. military, says Kirk Otterson, from the Office of Nuclear and Military Affairs at Los Alamos National Laboratory. It was larger and faster than a B-17 and could fly higher and farther. And, he adds, the B-29 could carry a larger bomb.

Nicknamed the Superfortress, the B-29 was a four-engine, propeller-driven bomber. First flown in 1942, it was the most sophisticated aircraft of its kind during World War II, Otterson says, and it was also the first bomber to house its crew in pressurized compartments. According to the Smithsonian’s National Air and Space Museum, the B-29 was designed by Boeing to fight in the European theater, but it also proved valuable in the Pacific theater, with as many as 500 planes operating there in a two-year period. When production of the B-29s ended in 1946, about 3,970 had been built.

Tibbets established himself as an adept B-29 pilot as well as a skilled military officer and leader. So upon landing a routine B-29 test sortie in Nebraska in September 1944, he found a man waiting for him with a message from a general in Colorado Springs. Tibbets was told to pack his bags and be in the general’s office at 9 a.m. the next day. He had no idea what the meeting was about or why he had been ordered to attend.

There, Tibbets was told the U.S. government’s most closely guarded secret—scientists in Los Alamos, New Mexico, were harnessing atomic energy to create the world’s first nuclear weapons, and Tibbets was being tapped to deliver an atomic bomb to help end World War II.

“When I got the assignment, [I knew] it was going to be an emotional thing,” Tibbets told The Columbus Dispatch in 2005. “We had feelings, but we had to put them in the background. We knew it was going to kill people right and left. But my one driving interest was to do the best job I could so that we could end the killing [of World War II] as quickly as possible.”

Tibbets was told by his superiors that if he was successful, he would be a hero. He was also told that he was the first choice of just three names considered to lead the mission.

Lieutenant General Leslie Groves, the Army officer who oversaw the Manhattan Project, wrote in his memoir that Tibbets was chosen because “he was a superb pilot of heavy planes, with years of military flying experience, and was probably as familiar with the B-29 as anyone in the service.”

Shortly after the meeting in Colorado, Tibbets took command of the newly created unit of 1,800 men who trained under extraordinary secrecy and security in an isolated, mostly uninhabited location in Utah at Wendover Airfield. Most of the airmen knew only as much as they needed to know to perform their duties. Tibbets himself handpicked the B-29 unit that would drop the atomic bombs and the Enola Gay’s crew, including the bombardier, navigator, and flight engineer—Thomas Ferebee, Theodore “Dutch” Van Kirk, and Wyatt Duzenbury—all of whom he’d flown with in Europe.


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Navy Captain William “Deak” Parsons (center) flew as the weaponeer on the Enola Gay, piloted by Colonel Paul Tibbets Jr. (right, standing). Parsons also helped prepare for the atomic bomb's delivery by modifying the aircraft and conducting field tests.

The bombs, Los Alamos

Meanwhile, work to design and build the first atomic bombs at Project Y—the code name for the secret laboratory in Los Alamos— continued as part of the Manhattan Project, says Alan Carr, senior historian at Los Alamos National Laboratory. This effort to beat the enemy in developing nuclear technology eventually resulted in Little Boy, the gun-type uranium bomb that would be released by Tibbets and his crew during the Hiroshima mission. Los Alamos scientists also developed Fat Man, the implosion-type plutonium bomb that another pilot, Major Charles Sweeney, and his crew delivered to Nagasaki three days later in a B-29 named Bockscar. It was the world’s second nuclear mission—and the last to date.

At 9,700 pounds, 10 feet long, and just over 2 feet in diameter, Little Boy was bigger than any bomb Tibbets had ever seen. The Enola Gay had to be specially modified to successfully carry and deploy it, Carr says. In the end, the bomb was released from the plane’s front bomb bay at an altitude of 31,000 feet. Little Boy exploded less than one minute later, about 1,500 feet above Hiroshima.

During the development of the two nuclear bombs, Tibbets recalled visiting Los Alamos three times to meet with scientists and military officials—including Robert Oppenheimer, Project Y’s lead scientist; General Groves; and others as the clandestine work on Little Boy and Fat Man progressed.

Initially, Tibbets didn’t understand the full depth of the bombs’ destructive nature, he said in the 2002 Guardian interview. One of the physicists explained it to Tibbets, who remembered thinking, “This was gonna be one hell of a big bang.”

Tibbets asked Oppenheimer how to get away from the bomb after it was released.

“[Oppenheimer] said, ‘You can’t fly straight ahead because you’d be right over the top when it blows up and nobody would ever know you were there,’” Tibbets recalled in 2002. “‘Turn 159 degrees as fast as you can and you’ll be able to put yourself the greatest distance from where the bomb exploded.’ I had dropped enough practice bombs to realize … I would have 40 to 42 seconds to turn 159 degrees. I went back to Wendover [Airfield, Utah] as quick as I could and took the airplane up. I got myself to 25,000 feet, and I practiced turning, steeper, steeper, steeper and I got it where I could pull it round in 40 seconds. The tail was shaking dramatically and I was afraid of it breaking off, but I didn’t quit. That was my goal. And I practiced and practiced until, without even thinking about it, I could do it in between 40 and 42 [seconds] all the time.”

The unique shapes of Little Boy and Fat Man meant the crews had to learn new techniques of releasing the bombs from the aircraft, Carr says. For nearly a year, hundreds of practice bombs were dropped from B-29s on targets surrounding the Utah airfield, while scientists and engineers in Los Alamos worked to determine the correct weight distribution and shape of the aerodynamically unique bombs. Meanwhile, special pits were constructed with hydraulic lifts to hoist the bombs into the B-29s’ bomb bays.


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The Enola Gay had to be positioned above a specially built bomb-loading pit to allow crews to transfer Little Boy into the aircraft’s bomb bay.

Los Alamos to “Destination”

In late May 1945, Tibbets and his unit transferred for additional training on Tinian island, where the Enola Gay would launch its mission several months later.

“One of three islands in the Northern Marianas, Tinian was chosen as the launching point for both the Hiroshima and Nagasaki missions based on its proximity to Japan and easy sea access for supplies,” Carr says. “The island’s code name was Destination.”

Meanwhile, U.S. bombings on different targets in Japan continued, making the B-29s an already familiar site in the skies above the country.

On July 14, 1945, completed bomb components and about half of the United States’ supply of uranium were taken by train from New Mexico to San Francisco, where they were loaded aboard a Navy heavy cruiser, the USS Indianapolis, and delivered to Tinian island less than two weeks later. Meanwhile, the other half of the uranium was flown to Tinian. Little Boy was then readied for the Hiroshima mission.

Around this same time, on July 16, 1945, Los Alamos scientists conducted the Trinity test, detonating a plutonium device, code-named the Gadget, in the New Mexico desert to verify the success of Fat Man in war.

By August, the plans for the first atomic mission were in place. In addition to the Enola Gay, many B-29s would participate, including a standby plane, a plane to take pictures, and another to collect data for scientific purposes. Weather planes also flew over the target cities before the missions.


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The crew of the Enola Gay.

Tibbets and his crew received notice that the sixth of August would be the day with the best weather for the mission above Hiroshima, and they began preparing. Around 4 p.m. on August 5, Tibbets got word that President Harry Truman had authorized the mission, according to the Guardian.

The Enola Gay was airborne less than 12 hours later.

The Hiroshima mission

As the Enola Gay drew nearer to its target on the morning of August 6, Tibbets recalled addressing his crew. “I said, ‘You know what we’re doing today?’ They said, ‘Well, yeah, we’re going on a bombing mission.’ I said, ‘Yeah, we’re going on a bombing mission, but it’s a little bit special.’ My tail gunner, Bob Caron, was pretty alert. He said, ‘Colonel, we wouldn’t be playing with atoms today, would we?’ I said, ‘Bob, you’ve got it just exactly right.’ So, I went back up in the front end [of the airplane] and I told the navigator, bombardier, flight engineer, in turn. I said, ‘OK, this is an atom bomb we’re dropping.’ They listened intently, but I didn’t see any change in their faces or anything else. Those guys were no idiots. We’d been fiddling round with the most peculiar-shaped things we’d ever seen.”

About six and a half hours after takeoff from Tinian, the Enola Gay was nearing Hiroshima. The skies were clear, and Little Boy was to be aimed at the distinctive T-shaped Aioi Bridge— an aim point that was chosen, Otterson says, because it was in the center of the city and could be easily seen from the air. Hiroshima itself was strategically significant because it headquartered the Japanese Army responsible for defending southern Japan and was a communications center and assembly area for troops.

With the target in sight, Tibbets counted down the seconds aloud for the crew three, two, one until the release of Little Boy. There was no doubt when the atomic bomb left the airplane.

“The [plane’s] nose lurched up—I mean it lurched dramatically—because if you immediately let 10,000 pounds out of the front, the nose has got to fly up. We made our turn, we leveled out, and at the time that that happened I saw the sky in front of me light up brilliantly with all kinds of colors,” Tibbets recalled. “At the same time, I felt the taste of lead in my mouth. And where we had seen the city on the way in, I [now] saw nothing but a bunch of boiling debris with fire and smoke and all of that kind of stuff. It was devastating to take a look at it.”

The Enola Gay and its crew had carried out a flawless mission with no opposition from Japanese fighters and delivered the first nuclear bomb used in war, Carr says.

The blast from Little Boy destroyed five square miles of the city, killed about 64,500 people, and injured countless others, according to a 1954 Army pathological study. Many more died in the ensuing months and years from injuries and radiation. (The blast from Fat Man, released above Nagasaki, is estimated to have killed about 39,214, according to the study.)

“I have been convinced that we saved more lives than we took,” Tibbets said. “It would have been morally wrong if we’d have had that weapon and not used it and let a million more people die,” he told an interviewer for the documentary The Men Who Brought the Dawn.


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“It seems our crew and airplanes made history or something,” Bob Caron wrote to his wife shortly after the Enola Gay bombed Hiroshima. Caron was one of the 11-person crew onboard the aircraft.

A few days after another crew dropped the second nuclear bomb during the Nagasaki mission, the Japanese government surrendered, ending World War II. As many as 50 million to 80 million (or more) people are estimated to have died during the war’s six years, Carr says.

Aftermath

No one has used nuclear weapons in combat since 1945, though the United States uses them every day as a deterrent.

Since creating the world’s first nuclear device 75 years ago, the Lab has been ensuring nuclear weapons are more effective, safe, and specific to the military’s needs, Otterson says.

“The work here at Los Alamos and our other national labs gives the warfighter—whether he or she is pulling the trigger, planning the targets, or maintaining the weapons system— the knowledge and, more importantly, the confidence essential to mission success,” Otterson says. He adds that as a retired Air Force officer who now works for the Lab, he believes that the partnership between the Department of Defense and Department of Energy is what secures our country’s nuclear-deterrent capability.

Carr concurs, adding, “Today at Los Alamos National Laboratory, we’re in the business of making sure another world war never happens. The Lab’s weapons work makes sure the world is a safer, more secure place. Nuclear weapons, as a deterrent, do that. Thus far, this transformative technology has helped render world wars obsolete.”

As just one reminder of its role as a means to the end of World War II, the Enola Gay now is on permanent display in the Smithsonian’s National Air and Space Museum’s Steven F. Udvar-Hazy Center.

None of the 12 crew members of the Enola Gay are alive today. Tibbets died at the age of 92 on November 1, 2007, in Columbus, Ohio. The last surviving crew member, Theodore “Dutch” Van Kirk, died in 2014 at 93.

After World War II, Tibbets and his fellow crew members received various military honors for their roles in the Hiroshima mission. Tibbets’ awards included the Distinguished Service Cross, the Legion of Merit, and the Distinguished Flying Cross. He was also part of a small group invited to meet with President Truman at the White House. According to Tibbets’ 2002 Guardian interview, Truman asked Tibbets, “What do you think?” Tibbets responded, “‘Mr. President, I think I did what I was told.’ He [the president] slapped his hand on the table and said, ‘You’re damn right you did, and I’m the guy who sent you. If anybody gives you a hard time about it, refer them to me.’”


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After World War II, Tibbets and his fellow crew members received various military honors for their roles in the Hiroshima mission. Tibbets continued to serve in the Air Force until he retired in 1966 as a brigadier general. He went on to help start and run an air taxi service in Ohio until he retired from the business in 1985. Tibbets died at the age of 92 in 2007.

After World War II, Tibbets continued to serve in the Air Force until he retired in 1966 as a brigadier general. He went on to help start an air taxi service in Ohio, and he helped run it until he retired from the business in 1985.

Before his death, Tibbets requested that his remains be cremated and that he not have a physical memorial, fearing it would become a gathering spot for nuclear weapons protests. His ashes were scattered by family members over the English Channel, where he’d flown many times in combat.

In various interviews in the decades after delivering the world’s first nuclear bomb, Tibbets never once expressed regret. Piloting the Hiroshima mission was his patriotic duty, Tibbets said time and again.

“I knew we did the right thing. … I thought, yes, we’re going to kill a lot of people, but by God we’re going to save a lot of lives,” he said.

But he also realized that once Little Boy was released, nothing would ever be the same. Albert Einstein famously said the world became a different place after the atom was split, referring to nuclear fission, the source of the atomic bomb’s explosive power.

Tibbets concurred. “That’s right. It has changed.”

He and the crew of the Enola Gay were there to see it the moment it happened.


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Little Boy and Fat Man were both carried by B-29s, named Enola Gay and Bockscar, respectively. The Enola Gay now is on permanent display in the Smithsonian’s National Air and Space Museum’s Steven F. Udvar-Hazy Center in Virginia. Photo: Eric Long/National Air and Space Museum