Harley Grimm

Transmitter of secret messages

April 26, 2023

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Harley Grimm, seen with his arm on a radio in the far-left picture above, was a second lieutenant with the 509th Composite Group, a secret unit of about 1,770 men recruited by the U.S. Army Air Forces to deploy the first atomic bombs during World War II. The components for the bombs were transported from New Mexico to a remote island in the North Pacific Ocean.

In the culminating moments of the Manhattan Project, Grimm was a keeper of secrets on Tinian Island who received and transmitted encrypted messages. He was 21 years old in August 1945 when an Enola Gay crew member, a private, reported in code to his superiors that the world’s first atomic bomb had been dropped over the Japanese city of Hiroshima. Was it Grimm — the main communications officer — who forwarded the message to President Harry S. Truman? If so, he never told his family. 

Although Grimm was never physically located at Los Alamos, he and other members of the 509th Composite Group played an integral role in the Manhattan Project and were honored at the Laboratory’s 50th anniversary celebration. 

Grimm died in 2009 at age 85.

Dad's unique perspective: 'This was our last shot'

By Gayla Grimm-Fogle

My dad served as the main communications officer on Tinian Island where Little Boy and Fat Man — code names for the atomic bombs — were launched in attacks against Japan.

Years ago, when I was a young woman of 18, I questioned my father about the war and how it ended. We were on an eight-hour road trip to visit my grandmother in Ohio. I was idealistic and trying to gain a better understanding of the atomic bomb and events surrounding that time.

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Gayla Grimm-Fogle with the 509th’s history.

I remember Dad explaining, “No one likes war. People don’t realize how close we were to losing, and this was our last shot.”

My father had a unique perspective. During the beginning stages of the Manhattan Project, he was assigned to duty at Wendover, Utah, as a member of the 509th Composite Group. On Dec. 17, 1944, by direction of the War Department and the Second Air Force, the 509th Composite Group was established at Wendover Field, chosen for its isolation as required by the secrecy of the 509th’s mission.

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Col. Paul Tibbets waves on Aug. 6, 1945, before departing for Hiroshima, Japan. Credit: www.atomicarchive.com

As the project and war progressed, my father was sent to Tinian Island and served as the communications officer. Col. Paul Tibbets headed up that group.

The 509th Composite Group was the weapon delivery arm of the Manhattan Project. Their mission was to plan and execute the deployment of the first atomic bomb.

Dad told me the men on the island had no idea what was on board the Enola Gay, Bockscar and other mission planes — they only knew that whatever it was, it was going to end the war.

I never asked Dad if he knew the secret before the rest of the men on the island did, and I don’t know what kind of messages he relayed.

He said that everyone on the island was so excited they lined both sides of the runway when Paul Tibbets and the others flew into Tinian before going on to Japan. Men were cheering and applauding; the thought of the war ending was electric.

Following their mission, the Enola Gay and other mission planes returned to Tinian. This time when they landed on the runway, no one was in sight, Dad told me. The enormity of this mission and its impact on the world was clearly understood.

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2nd Lt. Harley Grimm seated on the first row.

Years later, Gen. Leslie Groves, who had directed the Manhattan Project, said: “Faced as we were with innumerable uncertainties in our operations against Japan, it had always been comforting to know the 509th Group was willing and able to perform any task that was humanly capable of achievement. Tibbets and his men went about their work with quiet competence and accomplished their mission in the face of greater unknowns than had ever confronted a military organization.”

Over the years, Dad attended 509th Composite Group reunions. In 1993, the group was invited to attend the Laboratory’s 50th anniversary. I remember Dad was concerned about coming up to Los Alamos because of the new prevailing feelings about the atomic bomb, since the Cold War was over.

He was surprised by the warm greeting he and the other members received — cheers and displays of gratitude, including a sign held by a woman thanking them for what they had done.

Editor’s note: After the Manhattan Project, Harley Grimm’s distinguished career involved projects for the White House and space missions.

Gayla Grimm-Fogle is with Core Services (NIE-CS), and her daughter, Blythe Fogle, is with Site Infrastructure & Programs Software (SAE-3).