3/8 scale model of XPBM-1 built to demonstrate performance of full-scale flying ship. Tests of water-maneuvering, takeoff, and landing characteristics accurately predicted performance of full-size ship. About 100 flights made during test program. Span 43 ft 5.5 in; length 28 ft 6 in. Engine was a single Chevrolet engine, 4-cylinder, air-cooled, 120 hp with belt drive to prop on each wing. Internal fan cooled engine. Engine was made by G. L. Martin from Chevrolet Aircraft Corporation design. This was the only 3/8 scale, man-carrying model built and flown (at least, up to that time).