THE ACFT TOOK OFF WITH A CENTER OF GRAVITY BET 95.45 & 95.71 INCHES AFT OF THE DATUM & APRX 98 LBS BELOW THE MAX ALLOWABLE GROSS WEIGHT. THE MAX AFT CG LIMIT FOR ALL WEIGHTS WAS 94.6 INCHES. WX AT THE APRX TIME OF THE ACCIDENT WAS 400 FT CEILING, LIGHT SNOWSHOWERS, 4 MILES VISIBILITY WITH FOG, TEMP 29F, DEW POINT 29F. A SIGMET FOR MOD TO SEVERE ICING IN CLOUDS WAS ALSO IN EFFECT. THE ACFT IMPACTED IN A 30 TO 40 DEG LEFT BANK. IMPACT OCCURRED APRX 1800 FT FROM THE DEPARTURE END OF THE RWY. THERE WAS NO EVIDENCE OF INFLIGHT MECHANICAL MALFUNCTIONS OF THE POWERPLANTS. ALTHOUGH THEACFT ARRIVED AT JOHNSTOWN WITH ICE ON THE WINGS AND TAIL, THE PLT RECEIVED A FULL WX BRIEFING AND WAS AWARE OF THE ICINGCONDITIONS PRIOR TO HIS LAST TAKEOFF. THERE WAS EVIDENCE THAT THE PLT DID NOT DEICE THE ACFT'S WINGS AND TAIL PRIOR THE ACCIDENT FLT.