Single engine - two seat observation aircraft
On specific request by the Militair Vliegwezen/Aéronautique Militaire, the Belgian company Renard Constructions Aéronautiques modified two standard R.31 observation aircraft two incorporate an enclosed cockpit and a more powerful engine. A first as such improved machine (C/N 25010 of the R.31 production line) was modified with a large cockpit and was powered by a 1,050 HP 14-cylinder two-row air-cooled radial Gnome-Rhône 14N01 engine. Although this particular aircraft received the civil registration OO-ARY (CofA 378) in August 1936 it remained attached to the Etablissements Aéronautique (Ets Aé) for its entire Belgian career and testing phase. The final destination of this machine is somewhat obscure, but most sources indicate that it was brought up to Renard R.31 standards becoming N-10 (again). Other non-confirmed rumors relate tails of it being sold to Turkey, Spain or even Russia.
A second machine (probably c/n 25012 - see out of sequence serial of R.31 N-12) also received the enclosed cockpit, but was powered by an 835 HP V12 water-cooled Hispano-Suiza 12 Ybrs engine. During the delivery flight to the Militair Vliegwezen/Aéronautique Militaire the pilot Adj. Isidore Carijn (test pilot with the Ets Aé) felt signs of nausea caused by engine fumes in the cockpit and jumped to safety by parachute. The aircraft crashed near Leuven and was totally destroyed, unfortunately the exact cause of this accident was never established. (Daniel Brackx)