THE HELICOPTER WAS BEING USED TO PHOTOGRAPH AN OFFICE BUILDING. THE PHOTOGRAPHER STATED THAT AFTER EACH FLT OF ABOUT 10 MIN, THE PLT FLEW THE HELICOPTER TO THE LEFT & CENTER OF THE LANDING PAD, A FEW FEET ABOVE THE GROUND, THEN MOVED THE ACFT SIDEWAYS TO THE CENTER OF THE PAD & SETTLED TO A LANDING. AT THE END OF THE 3RD FLT, HE USED THE SAME PROCEDURE. HOWEVER, AS THE HELICOPTER WAS MOVING SIDEWAYS, THE LEFT SKID STRUCK THE GROUND 3 TIMES A FEW FEET APART, THEN THE RIGHT SKID HIT THE GROUND & COLLAPSED. THE HELICOPTER THEN ROLLED ON ITS RIGHT SIDE & WAS IMMEDIATELY ENGULFED IN FLAMES. BOTH OCCUPANTS EXITED THE BURNING CRAFT, BUT THE PLT DIED APRX 2 WKS LATER FROM BURNS. NO EVIDENCE OF A PREIMPACT PART FAILURE OR MALFUNCTION WAS FOUND. OTHER PLTS WHO FLEW THIS HELICOPTER STATED THAT IF THE CYCLIC CONTROL WAS BUMPED WITH THE ACFT CLOSE TO THE GROUND, THE PLT MAY BE UNABLE TO ADJUST QUICKLY ENOUGH TO PREVENT GROUND CONTACT.