Flight Details
The accident occurred during an on-demand for hire aerial sightseeing tour operating under visual flight rules. The tour was planned to circumnavigate a mountainous area on the island and visit an extinct volcanic crater in a mountain valley. Three helicopters departed with approximately two minutes between each departure. The accident pilot, employed by the operator 2.5 months earlier, was flying in trail behind the company's most experienced (chief) pilot and its second most experienced pilot. None of the pilots had received a weather briefing from an FAA-approved source, as required by the company's operations specifications.
Weather Conditions
During the flight, the pilots maintained radio contact with each other. The two lead pilots were a few minutes ahead as the accident pilot approached an area of the valley near the crater where inclement weather existed. The second pilot ahead of the accident helicopter reported that when he exited the crater near the accident site, he encountered heavy rain showers and lowering ceilings and visibilities.
Accident Sequence
Although the accident pilot attempted to follow the company pilots ahead of him, he did not observe the valley entrance to the Waialeale crater viewpoint and flew past it. As the flight progressed, the pilot encountered lowering ceilings, heavy intensity rain showers, and reduced flight visibility. The pilot became disoriented, misjudged his location, and while cruising toward what he believed was the prescribed crater entranceway, inadvertently entered instrument meteorological conditions. Just before the collision, the pilot transmitted to the pilots ahead of him that the weather was getting worse and that he could not see. The second pilot then provided a suggested heading that would take the accident pilot away from the mountainous terrain. The helicopter impacted the mountain on a heading nearly opposite of the one suggested.
Investigation Findings
The helicopter was subsequently recovered and examined. No evidence of any preimpact mechanical malfunction was noted. Between 30 and 45 minutes after the accident, one of the operator's tour pilots reported receiving the signal of an emergency locator transmitter (ELT). This pilot proceeded to pass by the general accident site area but was unable to observe the crashed helicopter due to the low level of clouds.