FAIRBANKS - A man likely competing in a wilderness race in Alaska's largest national park died last weekend after being thrown from his packraft in the Tana River, a large, glacial tributary of the Chitina River within Wrangell-St. Elias National Park.

The body of Rob Kehrer, of Palmer, was found at 4 p.m. on Sunday by an Alaska Air National Guard helicopter crew called in to search for him earlier in the morning.

Kehrer's body was found approximately 2.5 miles downstream from the location he was last seen by his rafting partner, Greg Mills, at 1 p.m. Saturday after he thrown out of his packraft, according to a news release issued by the National Park Service late Monday afternoon.

Though the Park Service couldn't confirm it, Kehrer was likely participating in the 33rd annual Alaska Mountain Wilderness Classic, a roughly 150-mile wilderness race from Thompson Pass to McCarthy that started on Aug. 3. Kehrer had competed in and finished multiple Wilderness Classic races, including the 2013 race in which he and Mills, were two of only five finishers.

The Wilderness Classic started on Aug. 3 at Thompson Pass just north of Valdez. It's unknown how many participants started the race or had finished as of Monday. Attempts to reach event organizer Luc Mehl were unsuccessful.

The Wilderness Classic is the longest, unsupported wilderness race in the state, though organizers go out of their way to de-emphasize the race aspect of the event in order to comply with Park Service regulations that prohibit races in designated wilderness areas, which much of the 13.2-million acre Wrangell-St. Elias National Park and Preserve is, according to chief ranger Peter Christian.

Kehrer's death would be the first-ever in the Wilderness Classic, which switches routes to a different part of Alaska every three years. This was the third and final year the route went from Thompson Pass to McCarthy, which is considered one of, if not the toughest, course the race has covered.

The Park Service's regional communications center was contacted by the Rescue Coordination Center at Joint Base Elmendorf-Richardson at 7:05 a.m. Sunday with a report that Kehrer was missing. Aerial and ground search efforts were carried out by Wrangell-St. Elias National Park and Preserve personnel in cooperation with the Alaska Air National Guard, pilots from Ultimta Thule Lodge, and locally hired ground searchers. The search group included three fixed-wing aircraft, two helicopters and eight ground searchers, as well as a National Park Service incident command team

The Tana River is known for extremely cold, swift, large water and difficult rapids, according to Christian. Kehrer's body was found just below what is considered the most difficult section of the river to negotiate, he said.

"It's got a well-earned reputation," Christian said of the Tana. "When the water is high it's big water."

Temperatures in the area have been in the 70s for the past two weeks so the water was likely higher than normal as a result of glacial melt, he added.

Kehrer was wearing a Type II personal flotation device, which U.S. Coast Guard define as the "classic" PFD. Coast Guard guidelines describe it as "for calm inland water where there is chance of fast rescue," as opposed to a Type I PFD, which Coast Guard guidelines say "is designed for extended survival in rough, open water."

A bigger, bulkier Type 1 PFD "is the best PFD to keep you afloat in remote regions where rescue may be slow in coming," according to Coast Guard literature.

According to aerial searchers, there were "some really big, nasty whirlpools and river hydraulics where he was last seen," Christian said.

According to a description of the Tana river in a 1994 book written by renowned Alaska paddler Andy Embick "the bold or unlucky boater running down the middle of the river in some of the drops would encounter true violence, easily flipping a 16-foot raft, and with holes that even a thrill-seeking, adrenaline-junkie, death-kayaker would avoid."

Christian said he is unaware of any packrafter that has floated the Tana, though Classic racers Gerard Ganey and Todd Tumualo successfully paddled it during the 2012 Classic.

The Park Service is aware of the existence of the Wilderness Classic but the event not permitted by the National Park Service because organized competitive events are not allowed in areas designated as wilderness, according to Christian.

"Nothing says they can't do what they did; we just can't permit it as a race," the chief ranger said. "It's a really admirable thing what those guys are doing. They're doing non-motorized, human-powered activities we'd like to see in parks in Alaska."

Contact staff writer Tim Mowry at 459-7587. Follow him on Twitter: @FDNMoutdoors.

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