The first results of the feasibility study on the Framatome convertible spectral shift reactor are presented. The generation rate of the plutonium core is estimated and the feasibility of reactivity control without soluble boron in hot conditions is reaffirmed. Cooling of the core (including fertile spectral shift rods) did not raise any major problem. To avoid reactivity accidents in case of core voidage, plutonium enrichment must be limited to a low value that is still compatible with high burnup on the condition that the spectral shift semitight-lattice design be used. In case of a loss-of-coolant accident, reflooding is performed without exceeding the appendix K limits.