THE PILOT'S INATTENTIVE FUEL SYSTEM MONITORING, AND THE RESULTANT TOTAL FAILURE OF THE AIRCRAFT'S POWERPLANT DUE TO FUEL EXHAUSTION. A FORCED LANDING WAS EXECUTED ON A STRETCH OF BEACH WITH SAND DUNES, AND THE AIRCRAFT WAS SUBSTANTIALLY DAMAGED DURING THE ROUGH TOUCHDOWN AND LANDING ROLL. THE PILOT EXPECTED TO HAVE AT LEAST ANOTHER HOUR OF FUEL, BASED ON PREVIOUS EXPERIENCE. FUEL QUANTITY WAS BEING JUDGED BY TIMING THE DURATION OF ACCUMULATED FLIGHTS; NO ELECTRIC FUEL QUANTITY INDICATOR WAS INSTALLED.