Flight History
A helicopter pilot was en route to pick up a passenger for a revenue flight under visual flight rules (VFR) when she encountered fog. She diverted from her intended destination and landed in a field. By the time the passenger arrived, darkness had fallen and dense fog had formed. The pilot and passenger then boarded the helicopter.
Witness Observations
A witness watched as the helicopter climbed vertically to a height just above the trees to its left and the utility lines to its front, and hovered for a few seconds. While hovering, the landing light cycled on and off two times. The helicopter then pitched nose down and accelerated forward. Instead of climbing, it accelerated forward in a shallow descent until it impacted the ground. The witness stated that the darkness and fog prevented him from reaching the accident scene without a light. Several other witnesses described similar conditions around the time of the accident.
Weather Conditions
Forecasted and actual recorded weather conditions in the area around the time of the accident were consistent with the witnesses' observations. The ceiling and visibility were significantly worse than the minimum values required by the company's operations specifications.
Operational Aspects
The company's operations specifications required the pilot to report any changes in her itinerary. No evidence was found that the pilot notified the operator of her initial deviation, subsequent landing in the field, or intent to depart after sunset. Postaccident interviews revealed that the operator could not clearly articulate its method for determining whether an aircraft was overdue, as no individual was charged with that duty for operations after normal business hours.
Wreckage Examination
Examination of the wreckage revealed no evidence of any preimpact mechanical malfunctions.