World's largest bomber (of its day) on first public demonstration flight at airfield in Dayton,Ohio. A Boeing Y1B-9 bomber taxis on ramp at Wright Field. The all-metal aircraft has open cockpits. Pilot in center of aircraft and crew member visible in nose gunner position. Change of scene shows a man standing behind the empennage of the parked bomber and moving its huge metal rudder slightly. The bomber taking off towards the camera over a grassy field, and later, in flight, .being observed and photographed from accompanying airplanes (partially visible).