In a little-known chapter of World War II, thousands of African-American troops trained to fly barrage balloons, defensive weapons used to protect Allied soldiers from dive-bombing enemy planes during the D-Day invasion. This is their story.

Part 2: Omaha Beach, France

William Garfield Dabney plunged from a flat-bottomed metal boat into waist-deep water holding his rifle over his head, staggering toward the Normandy coast. He breathed in a bitter mix of gasoline and cordite as his boots touched ground on Omaha Beach on June 6, 1944. Enemy guns strafed the sand around him, sip sip sip sip. Hot metal struck Dabney's leg. The Army corporal quickly taped the wound and kept going.