THE CERTIFICATED AIRLINE PILOT/FLIGHT INSTRUCTOR, THE PILOT-IN-COMMAND, WAS DEMONSTRATING A SINGLE ENGINE LANDING TO A CERTIFICATED PRIVATE PILOT/DUAL INSTRUCTIONAL STUDENT. DURING THE LANDING ROLL, THE AIRPLANE BEGAN TO DRIFT TO THE RIGHT. THE PIC ATTEMPTED TO CORRECT THE DRIFT BY INCREASING THE RIGHT ENGINE POWER AND APPLYING LEFT RUDDER. THE AIRPLANE RIGHT WING BEGAN TO SETTLE TO THE GROUND AND THE PILOT SHUT DOWN BOTH ENGINES. THE AIRPLANE RECEIVED DAMAGE TO THE RIGHT GEAR FLAPS AND PROPELLER. AN INSPECTION REVEALED THAT THE RIGHT GEAR STRUT WAS BROKEN AT AN INSPECTION HOLE PROVIDED BY THE MANUFACTURER. THE GEAR STRUT WAS THE SUBJECT OF A MANUFACTURER'S SERVICE BULLETIN AND SUBSEQUENT FAA AIRWORTHINESS DIRECTIVE THAT REQUIRED AN INSPECTION FOR CRACKS. MAINTENANCE PERSONNEL HAD RECEIVED THE SERVICE BULLETIN BUT HAD NOT SCHEDULED AN INSPECTION.