Ice makes plane tough to fly

The Cessna Caravan 208, the model of plane that crashed in the Cascades, has been involved in 52 crashes in the United States since 2000, according to the National Transportation Safety Board (NTSB).

The single-engine plane has been a popular choice of companies, adventurers and the military for shuttling large groups on short trips, but federal aviation officials in the U.S. and Canada have documented repeated incidents of pilot trouble while flying the plane in icy conditions.

The Federal Aviation Administration (FAA) and the Transportation Safety Board of Canada have both issued warnings to pilots flying the aircraft to avoid icy conditions, noting that inexperienced pilots have had problems in bad weather. The problem isn't with the plane, according to the FAA, but with pilots' ability to fly the aircraft during icy conditions.

The FAA -- which declined to comment on the plane Monday -- required pilots last year to post warning placards in Cessna Caravan 208 cockpits warning that "continued flight after encountering moderate or greater icing conditions is prohibited." The FAA and the Transportation Safety Board of Canada require Cessna 208 pilots to maneuver out of such conditions.

A Grand Caravan 208 -- the stretch version of the Caravan -- carrying nine Snohomish-based skydivers and a pilot disappeared Sunday while en route from the Boise, Idaho, area to Shelton, Mason County. Wreckage of the plane, built in 1994 and owned by Kapowsin Air Sports of Shelton, was found last night, according to Yakima County Emergency Management.

After the group left a skydiving event, it likely encountered temperatures hovering around freezing with some light rain and heavy clouds in the Cascades, according to the National Weather Service. Snow had fallen in the early evening, but there was no way to measure whether sleet was falling at the Stampede Pass weather station, the Weather Service said.

"I don't know the particulars on this crash, but every airplane has limitations," said Thomas Tilson, director of flight operations for Kenmore Air Express, which flies five Cessna Caravans. "If it was clear conditions, I wouldn't have a problem with it. But with the grade the conditions were [Sunday] I would not have dispatched one of our Caravans across the pass ... "

Tilson said his pilots worked closely with the FAA when the agency investigated the spate of Caravan crashes. He said the FAA discovered that almost all of the crashes were related to "pilot training issues or inexperience in the [weather] conditions."

But, he added, "the government determined last year there was nothing wrong with the aircraft."

Tilson said the FAA now requires all pilots planning to fly a Caravan "into known icing conditions" to pass an online course on such trips. Pilots who don't take it could face punishment by the FAA, Tilson said. He also said all pilots on staff at Kenmore have to take an eight-hour winter-flying course.

Tilson said that many beginning pilots have the illusion that because the Caravan has a single engine it can be flown like any other small plane, but carrying more people and cargo for longer distances. But, he said, many pilots of single-engine planes don't know the basics in flying in winter conditions -- paying attention to ice on the wings before takeoff and reacting to ice buildup on the nose, propellers and wings during the flight.

"The airplane is fine, but pilots may be over their head. This aircraft can get you into conditions that maybe you're not training to be in," Tilson said.

The name of the pilot and his experience level weren't immediately known.

About 30 people have been killed in accidents involving the Caravan -- including 10 aboard a plane that crashed shortly after taking off from Dillingham, Alaska, in October 2001. The FAA attributed the cause of that crash to "inadequate removal of ice accumulated while the airplane was on the ground."

A spokesman for Cessna told the Winnipeg Sun newspaper in December 2006 that more than 1,700 of the planes are in operation and the aircraft has logged more than 9.5 million flight hours worldwide since 1985.

The Transportation Safety Board of Canada has determined that Caravans shouldn't fly in anything more than light icing conditions, according to the Sun. That decision stemmed from an October 2005 crash that killed a pilot minutes after takeoff. An investigation found that ice buildup on critical surfaces of the plane kept it from maintaining altitude.

Jennifer Sullivan: 206-464-8294 or jensullivan@seattletimes.com

Seattle Times staff reporter Justin Mayo contributed to this report.