POOR JUDGEMENT OF THE PILOT, HIS DECISION TO ATTEMPT VFR FLIGHT IN INSTRUMENT METEOROLOGICAL CONDITIONS (IMC), AND HIS LOSS OF AIRCRAFT CONTROL DUE TO SPATIAL DISORIENTATION. FACTORS RELATED TO THE ACCIDENT WERE: THE PILOT'S LACK OF PROPER CERTIFICATION (QUALIFICATION), HIS POSSIBLE IMPAIRMENT DUE TO CONSUMPTION OF ALCOHOL, DARKNESS, ADVERSE WEATHER CONDITIONS, AND THE PILOT'S LACK OF INSTRUMENT AND FLIGHT EXPERIENCE.