Several of the biggest blueshifted events observed with BCS/Yohkoh Original Research Article

The flares on 11 July 1992, 22 April 1993, and 18 November 1993 observed with Yohkoh have been studied in this paper. Attention is paid to the dynamic behavior manifested by BCS data and the soft X-ray morphology. We find that chromospheric evaporation plays a role in these flares. For the former two flares, the chromospheric evaporation results from the non-thermal electrons, but for the flare on 18 November 1993, a thermal origin seems to be more possible.