VFR into IMC · NTSB WPR15FA070
CESSNA 172 — Sutter Creek, CA
| Date | December 24, 2014 |
| Location | Sutter Creek, CA |
| Aircraft | CESSNA 172 |
| Purpose of flight | Personal |
| Conditions | Day · Instrument Meteorological Cond |
| Phase / occurrence | Maneuvering Collision with terr/obj (non-CFIT) |
| Pilot age | 52 |
| Pilot total time | 900 hrs · Building experience |
| Time in type | Unknown |
| Fatalities | 2 |
Probable cause
NTSB findings
- Environmental issues-Conditions/weather/phenomena-Ceiling/visibility/precip-Below VFR minima-Effect on operation - C
- Personnel issues-Psychological-Perception/orientation/illusion-Spatial disorientation-Pilot - C
- Personnel issues-Task performance-Use of equip/info-Aircraft control-Pilot - C
- Personnel issues-Experience/knowledge-Experience/qualifications-Qualification/certification-Pilot - C
- Personnel issues-Action/decision-Info processing/decision-Decision making/judgment-Pilot - F
- Environmental issues-Physical environment-Terrain-Mountainous/hilly terrain-Contributed to outcome
What happened
The noninstrument-rated private pilot was conducting a personal cross-country flight. Upon return to his home airport, the pilot encountered forecast low ceilings and poor visibility; based on radar data, he was likely maneuvering in an attempt to locate the airport to land. The airplane impacted near the top of a hill at an elevation of 1,590 ft. A couple reported hearing a low-flying airplane with an engine that seemed like it was "struggling" or not producing power. Another witness in the area stated that she heard, but did not see, a low-flying airplane circling overhead and that the engine sounded like it was cutting out. The airplane then descended below a cloud layer, and she saw it heading in an eastbound direction. Although the weather conditions were conducive to the accumulation of carburetor and structural icing, based on the available evidence, the investigation could not determine whether this occurred. Examination of the airplane and engine revealed no evidence of a mechanical anomaly that would have precluded normal operation.
Instrument flight rule conditions with ceilings below 1,000 ft above ground level (agl), visibility below 3 miles in precipitation and mist, and mountain obscuration were forecast in the area at the time of the accident. However, a search of official weather sources revealed that the pilot had obtained no weather briefings. Reported observations at the destination airport (about 2 miles from the accident site) showed overcast ceilings of about 100 ft agl with a visibility of 1/4 mile about the time of the accident. Radar data showed that the accident airplane approached the area from the southwest (from the departure airport), overflew the destination airport about 4,000 ft agl, and continued tracking to the northeast for about 6 miles before descending and turning back toward the airport. In the minutes before the accident, radar data showed the airplane circling near the accident area at a low altitude. It is likely that the pilot encountered instrument meteorological conditions while maneuvering, which would have been conducive to spatial disorientation, and that the pilot subsequently lost airplane control due to spatial disorientation.