After last month's helicopter crash on Kaua'i killed seven people aboard, the National Transportation Safety Board (NTSB) released a preliminary report Wednesday.

The day after Christmas, December 26, 2019, an Airbus AS350 B2 helicopter operated by Safari Aviation Inc. was said to have been destroyed by 'impactful forces and a post-crash fire when it collided with terrain.'

It was the eighth and last scheduled 50-minute tour flight of the day.

"About 1645, an air tour pilot from a different company reported that he heard the accident pilot report "Upper Mic," which was a compulsory air tour reporting point that indicated the accident helicopter was exiting the Waimea Canyon and beginning a transition over to the Na Pali coastline via Koke'e State Park," the report reads.

Ten minutes after the helicopter was due to arrive back, the flight follower for Safari Helicopters notified the company's director of operations, and flight-locating procedures began.

 After an extensive search, the accident site was located the following day within Koke'e State Park.

"The helicopter impacted tropical mountainous terrain on a north facing slope at an elevation of about 3,003 ft mean sea level (msl) and came to rest at an elevation of about 2,900 ft msl," the report reads. "All of the helicopter's major components were located within the debris field, and the wreckage was largely consumed by a postcrash fire."

A witness along the Nualolo Trail within the state park reported weather conditions of about 20 feet visibility in rain and fog.

"He heard what he described as a hovering helicopter followed by a high-pitched whine," the NTSB reports.

The closest weather observation site to the accident was Barking Sands Pacific Missile Range Facility (PABK) about nine miles away. PABK reported wind from 310° at 12 knots, gusting to 15 knots; 10 statute miles visibility; few clouds at 1,200 ft, broken clouds at 3,400 ft and 4,700 ft, overcast clouds at 6,000 ft; temperature 70°F; dew point 57°F; and an altimeter setting of 29.90 inches of mercury.