Inadequate oxygen supply, pilot error blamed for fatal crash

(AP) Inadequate oxygen supplies and planning are being blamed for last year's fatal crash of a plane that was hundreds of miles off course before it plummeted into the backyard of a Winfield home, says an investigation by the National Transportation Safety Board.

William R. Cammack Jr., 56, of St. Paul, Minn., was flying from Montana to his home on March 17, 2006, when air traffic controllers in Minneapolis lost radio contact with his twin-engine Beech Baron 56TC. The plane was flying at 27,000 feet at the time.

The Federal Aviation Administration alerted the North American Aerospace Defense Command after the plane overflew St. Paul. Wisconsin Air National Guard F-16s intercepted the plane but were unable to make contact with Cammack. Michigan Air National Guard F-16s also were unsuccessful in making contact and tracked the plane until it crashed about 30 miles from Charleston.

Cammack's flight logs showed he liked to fly at high altitudes to get more efficiency from his engines. Oxygen is required at higher altitudes to avoid hypoxia - oxygen starvation - that can impair thinking and result in the loss of consciousness. The 38-year-old plane was equipped with an oxygen system.

NTSB investigators said Cammack was wearing an oxygen mask connected to a portable oxygen tank that was not approved for aviation use. That tank and the plane's built-in tank were both empty.

Cammack was the only person on the flight.

"The pilot's inadequate preflight preparation to ensure adequate supply of supplemental oxygen, and his inadequate in-flight planning and decision making, which resulted in exhaustion of his oxygen supply, and incapacitation from hypoxia during cruise flight" likely caused the crash, the NTSB said in its report.

The report said a survey of the airports Cammack used on his multiple-day flight "revealed no evidence the airplane's oxygen system or portable bottle had been serviced."

The crash was reminiscent of a 1999 charter jet crash that killed pro golfer Payne Stewart and four others. That plane flew halfway across the country on autopilot before crashing in a pasture in South Dakota. Everyone on board had apparently lost consciousness for lack of oxygen after a loss of cabin pressure, and the plane crashed after it ran out of fuel, investigators said.