The SBU-1 evolved as a two-seat dive bomber version of the XF3U-1, which competed for the Navy two-seat fighter purchase to ensure that Vought got a return on its fighter investment.  This aircraft was proposed as a land biplane replacement for the SU series.  It became the first aircraft of its type to exceed 200 mph.  It also featured a controllable-pitch propeller and NACA cowl and a twin row radial R-1535 P&W twin Wasp-Junior engine.

As expected, politics caught up with the two-seat fighter program and the Navy dropped it.  Although the XF3U-1 had been evaluated as a scout/ bomber, Vought decided to construct another airplane rather than modify the XF3U-1.  This airplane utilized the engine and most of the equipment from the XF3U1.  It completed its first tests in 1934, and a contract for 84 SBU-1’s was awarded in January 1935.

The SBU-1 was the first airplane of its type to exceed 200 mph and it also featured a controllable-pitch propeller and a new NACA cowl.  It was the first Vought airplane with a canopy to protect the cockpit occupants.  It also had adjustable cowling gills on the cowl trailing edge to obtain better control of the cooling air flow over the engine cylinders.  This feature permitted greater speeds and soon became standard for all air-cooled engines that incorporated a deep-chord cowl.  The design team headed by Rex Beisel of Vought and A. L. McCain and F.M. Thomas of Pratt & Whitney were awarded the prestigious Manley and Wright awards.