PINEWOOD SPRINGS, Colo. -- An experienced Boulder helicopter pilot, putting out hot spots within the Big Elk Fire died Tuesday evening when his chopper plunged into the rugged terrain. This occurred 11 days after two air tanker pilots were killed fighting the same fire, 7NEWS reported.

Gordon Knight, 52, was the only person on board the SA-315B Lama when it went down about 6:40 p.m., at the northwest corner of the burn area.

He was killed instantly, said John Bustos, a spokesman for the Roosevelt National Forest.

Knight had been filling up the chopper up with water at the Big Elk Meadows Reservoir, making water drops on the hot spots and patrolling the burn area when he made a desperate radio call, telling dispatchers that his chopper was going down, 7NEWS reported.

Fire crews mopping up and lighting back fires just north of the fire witnessed the crash, but it took them more than an hour to hike to the rugged, deeply forested crash scene, 7NEWS reported.

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The National Transportation Safety Board is investigating the cause of the crash and is expected to be at the scene Wednesday afternoon.

The downed chopper was the only aerial support being used on the Big Elk Fire.

The 4,413-acre blaze was completely contained last Friday, but because of the extreme fire conditions, small fires are still burning within its perimeter and will probably continue to smolder until winter snow blankets the region, fire officials said.

Knight is survived by a wife in Boulder.

Besides being an experienced pilot, Knight founded Twisted Pine Brewing Company in Boulder, Wolf Tongue Brewery in Nederland, and High Country Brewery in Estes Park.

Safety History

The water-dropping helicopter was leased from Geo-Seis Helicopters Inc. of Fort Collins to the city of Boulder and Boulder County. It was stationed at the Boulder Municipal Airport. It was manufactured by Aerospatiale, the same French company that builds the Concorde airliner.

According to NTSB reports, the Lama 315B model has had seven crashes in the United States since 1995. There were no fatalities and five injuries in those crashes.

The reports list a variety of causes for the crashes: two ran out of fuel, two experienced loss of power, two reported a popping sound prior to crash and one was a ground crew error.

The chopper was specially equipped for high altitude flying, having been designed to fly in the Himalayas, the Rocky Mountain News report.

Geo-Seis Helicopters has been in business since 1982. NTSB records show it has had two crashes related to the same make and model.

A pilot suffered minor injuries when a Geo-Seis chopper crashed in Cody, Wyo., in July 2001.

On Aug. 22, 1998, another Geo-Seis chopper lost engine power just 12 miles south of Naturita, Colo. The pilot suffered minor injuries.

The choppers are commonly used by the Forest Service to carry large buckets that can drop up to 150 gallons of water on the fires.

Number Of Firefighting Deaths Climb

This is the second fatal air accident related to the Big Elk Fire, which burned between Lyons and Estes Park. A World War II era P4Y-2 Privateer air tanker that was set to drop a load of slurry on the blaze crashed on July 18, killing two pilots.

The chopper went down about 3 miles west of where the air tanker crashed, 7NEWS reported.

"Once again, the Big Elk fire has killed, showing the danger that firefighters face even after a fire is contained. With many weeks remaining in the fire season, the men and women on the fire lines need our prayers and they need our help," Gov. Bill Owens said in a statement Tuesday evening. "Tonight, I am again imploring all Coloradans to be extremely careful in our dry forests during the dangerous weeks ahead."

A critical incident stress debriefing team was sent to the fire command center in Pinewood Springs to talk with the firefighters, who yet again, have to deal with losing another one of their colleagues.

Now there's a total of nine firefighting personnel killed in Colorado this fire season.

On July 2, a firefighter working on the Missionary Ridge Fire near Durango was killed when a tree fell on him.

And on June 21, five firefighters from Oregon on their way to the massive Hayman Fire, died when their van rolled on Interstate 70.