SACRAMENTO, Calif. (AP) -- An air tanker designed to drop retardant during wildfires crashed on a training flight in a remote forest, killing all three pilots on board, federal officials said.
The cause was under investigation, said Federal Aviation Administration spokesman Donn Walker.
The tanker was set to begin fighting fires next month after safety concerns grounded it and similar planes a year ago, federal officials said.
The plane, a P-3 Orion tanker, went down Wednesday evening in a rugged area of the Lassen National Forest, about 120 miles north of Sacramento.
The steep terrain prevented a rescue helicopter from landing at the crash site, forcing search-and-rescue teams to hike two to three miles to reach the wreckage, forest spokeswoman Leona Rodreick said. ''It's a fairly remote spot, and it took them a while to find a route in,'' Rodreick said. ''There are no roads or trails.''
The crash caused a fire that burned over two acres by Thursday, and a helicopter and 20 firefighters worked to contain the blaze, officials said.
Aero Union, the California company that owns the plane, identified the three aboard as pilots Brian Bruns, Paul Cockrell and Tom Lynch.
The plane had taken seven flights Wednesday as pilots who planned to work during the upcoming fire season underwent qualification checks.
There were no distress calls from the experienced crew, said Terry Unsworth, Aero Union's chief executive. ''We have no idea what happened,'' Unsworth said.
The plane, built in 1966 and formerly operated by the Navy, was one of 10 approved this week for a contract to return to the federal firefighting fleet, said Rose Davis of the National Interagency Fire Center. Aero Union won seven contracts for its P-3 Orions.
Last May, the U.S. Forest Service and the Department of the Interior terminated contracts for 33 large air tankers, citing concerns with public safety after two planes broke up in midair in 2002.
Aero Union had fought the grounding, arguing that it was unfairly punished for the problems of the Wyoming company that operated those planes, Hawkins & Powers Aviation.
An Associated Press investigation found Hawkins & Powers had a long history of crashes and safety problems. Air tanker pilots, industry experts and a government inspector said Aero Union maintained high standards while competing for government low-bid contracts.