This collection consists of one 5 by 3.75 inch black and white photograph of the Boeing B-29 Superfortress Enola Gay taken by H. M. O'Callaghan in 1945 on Tinian, Northern Mariana Islands.

Boeing's B-29 Superfortress was the most sophisticated propeller-driven bomber of World War II, and the first bomber to house its crew in pressurized compartments. Although designed to fight in the European theater, the B-29 found its niche on the other side of the globe. In the Pacific, B-29s delivered a variety of aerial weapons: conventional bombs, incendiary bombs, mines, and two nuclear weapons. On August 6, 1945, the Boeing B-29 Superfortress Enola Gay dropped the first atomic weapon used in combat on Hiroshima, Japan. Homer M. [H. M.] "Oak" O'Callaghan (d. 1990) served as an ordnance specialist with the US Army Air Forces during World War II. O'Callaghan enlisted in November 1943 and trained at the Aberdeen Proving Ground in Maryland in 1944. In 1945, O'Callaghan was assigned to the 509th Composite Group, 1st Ordnance Squadron Special (Aviation), stationed at Wendover Field, Utah and later on Tinian, Northern Mariana Islands. While on Tinian, O'Callaghan took a photograph of the Boeing B-29 Superfortress Enola Gay.