Nuclear Museum Logo
Nuclear Museum Logo

National Museum of Nuclear Science & History

Eugene S. Grennan

Flight Engineer on the Straight FlushHiroshima Mission

Tinian IslandWendover, UT
509th Composite GroupHiroshima MissionManhattan Project VeteranMilitary Veteran
The Straight Flush

Eugene S. Grennan served as a 2nd lieutenant in the 509th Composite Group. He was the flight engineer on the Straight Flush during the Hiroshima mission.

Related Profiles

Edward K. Allen

Los Alamos, NM

William J. MacLeod

Oak Ridge, TN

William MacLeod worked for the United States Engineer District Office.

William C. Barney

Nagasaki Mission

Sergeant William Barney was a Radar Operator assigned to the Bockscar’s original crew. He was a member of the 393rd Bombardment Squadron, a segment of the 509th Composite Group.

Floyd Owen Slate

Decatur, IL

Professor Floyd Owen Slate (1920-2008) worked on the Manhattan Project at Decatur, IL and at Columbia University.