 Eight companies submitted ten designs in response, evenly split between monoplanes and biplanes.Exemplifying the Bureau of Aeronautics' reluctance to fully embrace the monoplane configuration for carrier-based aircraft, the XSB3U-1 was proposed as a more conventional alternative to Vought's XSB2U-1, which was designed as a modern monoplane.The XSB3U was modified from the last production SBU Corsair, using essentially the same airframe, including a fully enclosed cockpit, and Pratt & Whitney R-1535 radial engine, but with a more streamlined surface and cowling.