The pilot reported that, during the right downwind in the traffic pattern, he was about one quarter mile from the runway, which was "too close". He added that, "during a poorly planned and executed base to final approach", he performed an "uncoordinated" right bank at about 45°, and the right wing dropped, which resulted in a descending roll to the right. He attempted to recover, but the airplane impacted terrain.
The airplane sustained substantial damage to the fuselage and the right wing.
The pilot reported that there were no preaccident mechanical failures or malfunctions with the airplane that would have precluded normal operation.