ESTES PARK, Colo — Witnesses saw a firefighting air tanker roll upside down before it crashed into a mountain near Estes Park, killing the pilot, according to a preliminary report from the National Transportation Safety Board (NTSB).
Pilot Marc Thor Olson was fighting the Kruger Rock Fire when his single-engine air tanker crashed around 6:36 p.m. Nov. 16. The flight was believed to be the first time a fixed-wing aircraft would be used to fight a fire at night.
> Video above: Remembering the man killed fighting the Kruger Rock Fire from the air at night
According to the Larimer County Sheriff's Office, Olson reported turbulent winds over the fire and said he was going to make one more pass before returning to the airport in Loveland. He crashed moments later.
According to the NTSB report, video showed the plane's wing rocking as it approached the intended air drop location. Two witnesses said they saw the plane roll inverted, and did not see it descend into the terrain.
One of the witnesses was in radio communication with the pilot, the report says. He said he did not hear Olson transmit any problems with the airplane or make any distress calls before the crash.
Investigators found the airplane wreckage upright. They said the evidence indicated a low-speed, nose-down impact with the sloping and wooded terrain. There was no ground scarring before the wreckage.
The report released Wednesday was a preliminary report. The full NTSB investigation into the cause of the crash will likely take a year or more.
The Kruger Rock Fire burned about 147 acres southeast of Estes Park. It was declared fully contained on Nov. 20. No structure damage was reported.
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