Accident Details
On November 4, 2001, at approximately 1715 hours, a helicopter was prepared for flight at a nearby airport. The helicopter departed about 15 minutes before the accident and proceeded to a location believed to be the pilot's property. The helicopter subsequently collided with trees in an avocado grove and then struck terrain. The wreckage was discovered by farm workers on the morning of November 6, 2001, approximately 100 yards from a landing pad on the pilot's property. The pad was situated at an elevation of about 1,600 feet and was about 10 miles from the departure airport.
Background
A certified flight instructor (CFI) at the departure airport observed the pilot preparing the helicopter for flight around 1715. The CFI reported that visibility was 4 miles with haze and deteriorating. The pilot regularly approached the landing pad from the northeast. The pad was unlit.
Weather Conditions
The automated surface observation station at the departure airport (field elevation 28 feet) reported at 1714: skies clear, visibility 4 miles, mist present, and a temperature/dew point spread of less than 3 degrees Fahrenheit. By 1745, broken clouds had formed at 1,000 feet; visibility and temperature/dew point spread remained unchanged. Sunset occurred at 1659, civil twilight at 1724, and nautical twilight at 1753.
Aircraft Information
Investigators found no anomalies that would have precluded normal operation of the helicopter or its engine. The helicopter was not equipped with an artificial horizon. A placard on the instrument panel stated that the pilot must have sufficient illumination to operate by outside light sources. The Pilot Operating Handbook included a limitation that the pilot must maintain orientation at night by lights on the ground or by adequate celestial illumination.