On November 21, 1999, about 1015 hours Pacific standard time, a Smith Aerostar 600, N97CC, descended into the Pacific Ocean near Avalon, California. The airline transport rated pilot, the sole occupant, received fatal injuries. Visual meteorological conditions prevailed for the personal flight. The aircraft, owned and operated by the pilot under the provisions of 14 CFR Part 91, was destroyed in the collision sequence and sank to the ocean bottom. No flight plan was filed for the local area flight, which originated at Fullerton, California, about 0930. According to a family member, the pilot was accomplishing a post maintenance flight check. Review of information and radar data provided by the Federal Aviation Administration (FAA) disclosed that the pilot was receiving visual flight advisories from Southern California Terminal Radar Approach Control. At 1015, radar contact was lost on the 200-degree radial of the Seal Beach VOR at 20 miles. Recorded radar data revealed that the mode C return was level at 4,900 feet mean sea level (msl) and exhibited a slowing ground speed. The secondary beacon returns then started a descending right spiral and radar contact was lost at 1,000 feet msl. The pilot's body was recovered from the ocean and an autopsy was conducted by the Los Angeles County Coroner's office. According to the autopsy report, the pilot had experienced sudden cardiac death secondary to an acute myocardial infarction due to atherosclerotic coronary artery disease. The attesting pathologist opined that the event began from 30 minutes to several hours before the pilot's death. Tramadol, a painkiller not approved by the FAA for flight, was detected in blood and tissue samples submitted for toxicological tests. The pathologist stated that the drug may have masked the chest pain symptoms of the cardiac event. The aircraft was not recovered. Review of the maintenance records disclosed that on November 5, 1999, the oil was changed on both engines. During engine run-up a "hot" or non-grounding magneto was found on the right engine. A loose "P" lead for grounding the magneto was discovered and reattached. At the same time, a broken exhaust flange was discovered on the No. 6 engine cylinder. Subsequently, the entire exhaust system and a gas temperature probe were replaced on the right engine. According to maintenance records, the last annual inspection occurred on July 16, 1999.