Rohrbach Roland (Germany, 1926) Rohrbach Romar (Germany, 1928) Romano R-16 (France, 1933)[52] Ryan Navion one off modification (US, 1961) SABCA S.11 (Belgium, 1931) Saunders Severn (UK, 1930) Saunders Valkyrie (UK, 1926) Saro Windhover (UK, 1930)