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Glacier Flying

  • Glacier Flying
    This building behind the K2 Aviation terminal at Talkeetna (Alaska) Airport is decorated with local artifacts. Photo by Mike Collins.
  • Glacier Flying
    Veteran pilot Stan Steck, at far right, gives a safety briefing on the de Havilland Turbine Otter to a load of climbers before flying them to the Denali base camp at the 7,200-foot level of the Kahiltna Glacier. Photo by Mike Collins.
  • Glacier Flying
    Skiiers make their way across the Kahiltna Glacier. They are returning to the Denali base camp after skiing--or, perhaps, ferrying food and supplies to their next camp location. Photo by Mike Collins.
  • Glacier Flying
    Retractable wheel skis allow K2 Aviation to land its de Havilland Turbine Otters on glaicers like the Kahiltna Glacier, adjacent to the Denali base camp. Photo by Mike Collins.
  • Glacier Flying
    Although turbine-engined de Havilland Turbine Otters now comprise most of the K2 Aviation fleet, the Talkeetna, Alaska-based company also operates a few radial-engined de Havilland Beavers. Photo by Mike Collins.
  • Glacier Flying
    A de Havilland Turbine Otter, operated by K2 Aviation, climbs from the Talkeetna (Alaska) Airport where the Part 135 carrier is based. Photo by Mike Collins.
  • Glacier Flying
    A de Havilland Turbine Otter operated by K2 Aviation approaches fog-shrouded One Shot Pass. When it's clear, the pass provides the most direct route between Talkeetna, Alaska, and the Denali base camp on the Kahiltna Glacier. Photo by Mike Collins.
  • Glacier Flying
    Climbers unload their gear from a de Havilland Turbine Otter after landing at the Denali base camp. Plastic sleds are ubitquious here, used to haul equipment and even serving as runway markers. Photo by Mike Collins.
  • Glacier Flying
    Chip Sonn, who has flown for K2 Aviation more than six years, guides a de Havilland Turbine Otter toward the Denali base camp. The camp is located at 7,200 feet msl on the southeast fork of the Kahiltna Glacier. Photo by Mike Collins.
  • Glacier Flying
    This de Havilland Turbine Otter has just landed on the Kahiltna Glacier. Friction on the ice heats the skis, and it's important to cool them--by stopping briefly, moving downhill slightly, then stopping again several times--to keep them from sticking to the ice. Photo by Mike Collins.
  • Glacier Flying
    This de Havilland Turbine Otter, operated by K2 Aviation, sits pointing downhill after landing on the Kahiltna Glacier. It delivered a load of climbers to the Denali base camp, seen to the left of the airplane. Photo by Mike Collins.
  • Glacier Flying
    This de Havilland Turbine Otter, operated by K2 Aviation, sits pointing downhill after landing on the Kahiltna Glacier. It delivered a load of climbers to the Denali base camp located here. Photo by Mike Collins.

Landing uphill, on iceLanding uphill, on ice

Glacier pilots make it look easy

Chip Sonn peers from beneath a baseball cap, eyes squinting despite his dark sunglasses. He’s all business as the red-and-white de Havilland Turbine Otter claws its way toward 10,500 feet msl. Above, a sunny sky has given way to bright white clouds. Below, the terrain—where it’s not stark, nearly vertical rock—remains covered in seemingly featureless white snow.

The weather is changing as Sonn ascends Denali, formerly Mount McKinley, but this is normal on the highest peak in North America. With a summit elevation of 20,310 feet, Alaska’s Denali is a popular climb. His passengers leave the swiftly moving Susitna River and the lush spring greens of the tundra behind as Sonn flies them toward the Denali base camp, at 7,200 feet msl on the southeast fork of the Kahiltna Glacier.

The straight-line distance from Talkeetna Airport is less than 50 nautical miles, but the route is longer as the single-engine turboprop weaves among much lower peaks until reaching One Shot Pass—the most direct route to the base camp—at 9,500 feet.

“The mountain is alive—the environment is alive. The tectonics of the whole thing. You’re dealing with 30 billion years and 60 billion years,” Sonn explained. “And there’s a culture of people that go out there and thrive in it. The frostbite, the hypothermia, the emotional challenges.”

And he’s noticed more changing on Denali than today’s weather. “You’ll see one point on the rock and know it used to be under the snow.” Talkeetna was under 4,000 feet of ice 20,000 years ago, he said, and some areas have lost 350 feet of ice since the 1940s. “We’re being challenged by the roughness of the [glacier] strips earlier in the season,” he added, because there sometimes isn’t enough snow to refresh the surface.

Sonn has been involved in Alaskan aviation for 20 years. He started as a guide, loading airplanes with boats and riding in the right seat on flights out to gravel bars. “Inevitably they let you fly,” he said, and Sonn earned his certificate in Alaska. “I was learning from aviators with incredible backcountry experience. I realized how valuable that was, and I paid attention.

“And it was cool airplanes—Super Cubs, Maules. It’s ‘hop in, let’s go.’” People use airplanes here like they use cars elsewhere, he said. “I was lucky to have that experience.” Also a seasoned skier, emergency medical technician, and skydive pilot, he’s flown for K2 Aviation for seven years.

“I learned a lot about glacier flying here. This is one of the most unique environments for it,” he said, adding that he appreciates his employer’s added safety nets of flight tracking and information sharing. “K2 is an open book on information.”

Contrast that with private pilots transiting the area, who are on their own. “On mountain frequency, they’ll ask us lots of questions—and about snow conditions. We encourage it,” he said. Sonn and his peers have the same attitude when a pilot walks into their office. Flight Service is helpful, too; there’s a station on Talkeetna Airport. “If anyone flies up here without adequate knowledge, it’s their own fault.”

Landing on a glacier, flat light conditions are most difficult, said Stan Steck of Anchorage (see “Landing on a Glacier,” p. 73). “Flat light and bad weather are the riskiest conditions,” he said. And landing is more complicated than a glassy-water landing in a seaplane, “especially when there are multiple slopes. A short glassy-water landing is a better comparison.”

Steck retired from the National Park Service as a pilot at Denali National Park in 2005. When his wife suggested in 2011 that he get a job, “I came to Talkeetna because I love flying in the mountains. I had a skill set that was unique to this area.” Although the skills aren’t especially difficult, he said, it does take exposure, practice, and feedback. “And you have to have fun—otherwise your passengers won’t.”

One of his most surprising lessons was how easy it is to get stuck in the ice. “You’re taught to land and pull the power. In the ski world you might not want to do that; it could lead to you getting stuck. And it takes a lot of labor to get unstuck.”

He has adapted well to flying tourists instead of researchers. “Our mission is to put smiles on people’s faces,” Steck said. “There’s no sense in flying in turbulence. [Passengers] won’t remember the views we give them; they’ll remember being sick.”

“K2 is such a safety-oriented business, in everything we do,” Sonn added. “Company policy is built on having ways to get out of those canyons. We can take off out of base camp, and our way out can be shut down. There’s no forecasts; it’s all experience. Are we going to have fog on the glacier, or fog in the pass? We’re always landing uphill and taking off downhill. It takes a while to get used to it. The landing areas are huge but we have no go-arounds.”

Landing uphill, on ice

Sights not to miss

From Talkeetna, K2 and other operators offer a variety of aerial tours of Denali. K2’s options range from a one-hour Denali Experience Flight Tour to a two-hour Summit Tour; glacier landings can be added, weather permitting, to any tour.
Tourist flights do not land at the Denali base camp on the Kahiltna Glacier; that landing area is reserved for climbers and support flights. Sightseeing flights often land in the Sheldon Amphitheater—named for Don Sheldon, the famous Alaskan bush pilot who pioneered glacier landing techniques—on the Ruth Glacier. Landings can be made on other glaciers, as well.
The National Park Service requires the purchase of a pass unless you have traveled or will be traveling into the park within a week of your flight. More information is on the K2 website (

Map by Baker Vail

Landing on glaciers

  • Landing on glaciers
    After landing uphill—to the left of the row of plastic sleds partially buried in the snow, to help glacier pilots judge their height above the surface—Chip Sonn prepares a K2 Aviation Turbine Otter for the return to Talkeetna, Alaska. The skiplane is at 7,200 feet msl on the Kahiltna Glacier; the base camp used by Denali climbers is a few hundred feet to the right.
  • Landing on glaciers
    “The mountain is alive—the environment is alive.The tectonics of the whole thing. You’re dealing with 30 billion years and 60 billion years. And there’s a culture of people that go out there and thrive in it. The frostbite, the hypothermia, the emotional challenges.” —Chip Sonn, glacier pilot
  • Landing on glaciers
    This skiplane has landed, turned around, and stopped, facing downhill, to facilitate its next operation: a glacier takeoff.
  • Landing on glaciers
    One Shot Pass is a notch in the flank of Mount Hunter that, when weather allows, offers aircraft the most direct route between Talkeetna and the Kahiltna Glacier base camp.

Spending a night on the glacier is a good decision if the weather changes for the worse, and there’s survival equipment in the aircraft, he added. “It’s not really survival; it’s a precautionary concept. It’s OK to not land, it’s OK to come back [to Talkeetna]—especially if the weather’s changing or the fog’s rolling in.” The company’s dispatchers are great, he added, and the base camp provides weather information at 8 a.m. daily and any time the weather changes.

Sonn credits Suzanne Rust—who, with her husband, Todd, owns K2 Aviation—for the safety culture. One of several operators authorized by the National Park Service to fly into Denali, Talkeetna-based K2 is operated by the Rust family, which has been flying Alaska’s backcountry since 1963.

And like the mountain itself, the company has seen change over the past few years, Rust said. Most noticeably, it’s transitioning from its venerable Cessna 185s to larger aircraft, and in 2018 operates five de Havilland Turbine Otters. “It allows us to land later during the season,” she explained, because by mid-July the ice is getting too rough for the 185s. Larger airplanes also let the company fly the same number of passengers on fewer flights, which reduces sound impacts within the park boundaries.

K2 likes to see pilot candidates with at least 2,000 hours of experience, she said, but might consider lower time if it’s the right kind of time—for example, considerable Alaska backcountry experience.

Like her staff, Rust enjoys living and working in Alaska. “We have a special kind of aviation. We’re here to make people happy,” she said. “If it’s good, we’ll go—if not, we’ll come back. We don’t have to deal with the pressures others do.”

The season ramps up in early May, and continues through the end of September. Some 1,100 people climb the West Buttress—Denali’s easiest and most frequently climbed route—each year. “For us, the climbing part is a very small part of the business,” Rust said, “maybe 10 percent.”

And as Denali constantly changes, so does K2’s passenger mix. “Ski tourism is making our season start earlier and earlier,” Sonn observed. A few skiers want to be flown onto the mountain in February or March, “as soon as there’s light,” he said—and many are one-way passengers, skiing downhill to a river, then inflating a boat and floating back to civilization.

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Mike Collins

Mike Collins

Technical Editor
Mike Collins has worked for AOPA’s media network since 1994. He holds a private pilot certificate with an instrument rating.

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