The pilot was a physician, and the purpose of flight was to attend to his patients for scheduled appointments at a medical office near the destination airport. He had frequently flown into the airport, which was located in mountainous terrain. Review of flight track data found that the flight followed a route that was consistent with what the pilot had entered into a flight planning application shortly before flight. Upon arrival in the destination airport area, the pilot announced over the airport’s common traffic advisory frequency that he would circle to land. There were no further communications recorded from the pilot.Flight track data revealed that the airplane completed a total of three approaches to the runway. The weather conditions reported at the time of the approaches were low instrument flight rule (IFR) conditions. Based upon hourly weather observations at the airport, surveillance video, and a pilot-rated witness located at the airport, visibility was likely restricted to 200-300 ft due to fog and low clouds. Based upon a witness statement and flight track data, it is likely that on each approach the pilot descended to a lower altitude in search of the runway environment. On the third and final approach, the airplane impacted a ravine and steep rock wall about 50 ft below the runway elevation and 375 ft short of the runway threshold (the runway sat atop of rising terrain, with a valley below). Based on this information, it is likely that the pilot descended below the runway elevation on final approach, which resulted in the pilot’s controlled flight into terrain while searching for the runway environment. The pilot did not file a flight plan, nor communicate with air traffic control during the flight after departing under visual flight rules (VFR). The airport had one published GPS circling instrument approach procedure. The airplane’s flight path and altitude were not consistent with this approach, and the weather conditions were far below published visibility and cloud ceiling minimums for the approach. Additionally, a few weeks before the accident, the airport had Page 2 of 16 ERA23FA048issued a Notice to Air Mission, which advised that the runway end identifier lights, and all airport lights, were out of service. Due to the extremely low visibility and clouds, it is unlikely that the runway lights would have aided the pilot’s search for the runway environment.  Review of the pilot’s past flights into the accident airport found that he routinely conducted teardrop circling maneuvers to land in poor weather. Within the 90 days before the accident, a total of four flights were identified in which the pilot was able to land by circling over the airport under IFR or low IFR weather conditions. The approaches were likely conducted under VFR and into instrument meteorological conditions (IMC), given that the altitudes and flight track flown were not consistent with the published instrument approach procedure. There was one additional flight located in the pilot’s logbook, about four years before the accident, where remarks noted that he attempted an approach to the accident airport to check the low IFR conditions. The remarks noted that the low IFR conditions were confirmed during an approach, and he subsequently diverted to a nearby airport that he also frequently flew to. This nearby airport’s weather reporting station, around the time of the accident, reported similar low IFR conditions to the accident airport.    There was no record that the pilot received a weather briefing before the flight, and it is not known what information he reviewed. Had he checked the weather, he would have seen that the destination airport was reporting low IFR conditions, as well as the other nearby airport that he had diverted two on the flight four years prior. While the pilot had logged several hours of actual instrument flight experience in the preceding 90 days before the accident, he did not possess instrument currency for the accident flight (nor had he filed an IFR flight plan).The investigation found that the pilot routinely flew VFR to the accident airport and conducted circling maneuvers to land into IMC. The pilot’s repeated VFR flight into IMC, his decision to fly an approach that was not consistent with the instrument approach procedure published for the airport, and lack of instrument currency demonstrated an anti-authority hazardous attitude, in which he repeatedly disregarded regulations and demonstrated poor judgement. It is possible that the pilot’s decision to conduct the flight was in-part influenced by his scheduled appointments with his patients, which would have increased the external pressures to complete the approach to landing. Toxicology testing revealed that the pilot had used phentermine, a stimulant and anorectic medication used to treat obesity. The drug also has a possible side benefit of increased alertness. Methamphetamine was also detected at low levels in some of the pilot’s tissue specimens; methamphetamine is also a central nervous stimulant and can be medically indicated to treat obesity. Due to extensive injuries, no blood specimens were available for toxicological testing, so whether these medications were at therapeutic levels could not be determined. The pilot’s use of prohibited substances, in addition to his decisions to habitually fly to the airport under VFR and into IMC, is a further example of poor judgment and an anti-authority Page 3 of 16 ERA23FA048hazardous attitude. The detection of these medications was more emblematic of his disregard of safety and rules than of impairment. Thus, while stimulants were detected in the pilot’s tissues, it is unlikely that the effects of the pilot’s use of phentermine and methamphetamine contributed to this accident.The sedating antihistamine chlorpheniramine was also detected in the pilot’s liver and muscle tissue, which is commonly taken to treat colds. Due to the lack of specimens available for toxicology testing, it is unknown whether the pilot had experienced side effects or if chlorpheniramine was at therapeutic levels. Thus, it could not be determined if the effects from the pilot’s use of chlorpheniramine was a factor in this accident.