Roger Boisjoly, voiced Challenger concerns

NEPHI, Utah -- Roger Boisjoly, a NASA contractor who repeatedly voiced concerns about the space shuttle Challenger before it exploded, has died. He was 73.

Boisjoly died of cancer on Jan. 6 in Nephi, his wife, Roberta Boisjoly, said.

The 1986 Challenger tragedy shocked the nation. Seven astronauts, including a schoolteacher, were killed when the shuttle disintegrated 73 seconds after liftoff from Cape Canaveral, Fla.

Boisjoly, an engineer at rocket-builder Morton Thiokol Inc., warned in 1985 that seals on the booster rocket joints could fail in freezing temperatures. "The result would be a catastrophe of the highest order -- loss of human life," he wrote in a memo.

On the eve of the ill-fated flight, Boisjoly and several colleagues reiterated their concerns and argued against launching because of predicted cold weather at the Kennedy Space Center. They were overruled by Morton Thiokol managers, who gave NASA the green light.

After the accident, Boisjoly testified to a presidential commission investigating the Challenger accident. The group determined that hot gases leaked through a joint in one of the booster rockets shortly after blastoff that ended with the explosion of the shuttle's hydrogen fuel.

Boisjoly said he was shunned by colleagues and neighbors after emerging as a whistle-blower. He took an extended leave of absence while Morton Thiokol worked on a redesign of the rocket joint.

Later, he toured the country and spoke about his experience. He received awards from the American Association for the Advancement of Science and the Institute of Electrical and Electronic Engineers for trying to halt the Challenger launch.

Roberta Boisjoly said her husband continued to receive emails from students and others about his role. "I'm very proud of what he did. It took a lot of courage," she said. "That's who he was."

-- AP