 To test the suitability of the R-Xa he made three tours of Poland and then made a five-day round trip from Warsaw via Bucharest, Istanbul, Rome, Turin and London, a distance of .This experience led to modifications to his aircraft, including fuel distribution, a strengthening of the undercarriage, together with aerodynamic refinements including a Townend ring and spatted wheels.After the changes the type was sometimes referred to as the R-Xa bis.