On January 27, 2001, at 1210 hours Pacific standard time, a Beech BE-55, N1280Z, landed gear-up at San Bernardino, California. The airplane sustained substantial damage; the certificated flight instructor and his certificated student were not injured. The airplane was being operated under 14 CFR Part 91 by the student/owner when the accident occurred. The local flight originated from Cable Airport, Upland, California, California, at 1114. Visual meteorological conditions prevailed at the time and no flight plan had been filed. According to San Bernardino Police Department officers, the student stated that he was receiving flight instruction for his commercial certificate and had just completed two touch-and-go takeoffs and landings. He was on his third touch-and-go to runway 24 at San Bernardino International Airport when according to his written statement, he forgot to lower the landing gear prior to touchdown. The instructor told officers that he did not hear the gear warning horn prior to the accident.