Mooney M20E accident near Julian, California, October 9, 2013

The NTSB's narrative final · quoted from the NTSB record

The pilot departed on a 65-mile cross-country personal flight over mountainous terrain with a planned destination of his home base. The pilot contacted air traffic control (ATC) for visual flight rules (VFR) flight following. During the course of the flight, the pilot experienced turbulence at 8,500 ft and descended to 4,500 ft. When an ATC controller informed him that he was in an area of high terrain, the pilot stated that he was familiar with the area and could maintain his own terrain obstruction clearance. Several minutes later, radio and radar contact were lost, and an alert notice was issued several hours later. Sheriff's helicopters attempted to search the area but had to abandon their efforts due to inclement weather. The following morning, the airplane was located on the side of a mountain with a 50-percent grade at an elevation of 4,200 ft and near the last radar contact. Postaccident examination of the recovered airframe and engine revealed no evidence of preimpact mechanical malfunction or failure that would have precluded normal operation. Weather reports for the area indicated that the mountainous terrain was most likely partially obscured by clouds; therefore, it is likely that the pilot was maneuvering to maintain VFR flight when the airplane collided with the mountainous terrain. The sedating antihistamine diphenhydramine was found in cardiac blood. However, diphenhydramine undergoes significant postmortem redistribution. At the level detected, the investigation was unable to determine if the medication would have impaired the pilot around the time of the accident.

The complete narrative as the NTSB published it. The NTSB's docket holds the report as a PDF and any photographs, statements and other documents from the investigation.