BRIGHAM CITY, Utah, March 22 (UPI) -- Bob Ebeling, one of the engineers who tried to stop the doomed launch of the space shuttle Challenger, has died. He was 89.
Ebeling died Monday in Brigham City, Utah, after a long illness, his daughter Kathy Ebeling said.
Consumed by guilt over much of the past 30 years, Ebeling, his family said, was recently able to come to peace with the 1986 disaster with the help of National Public Radio listeners.
"It was as if he got permission from the world," says his daughter Leslie Ebeling Serna. "He was able to let that part of his life go."
Ebeling was interviewed for an NPR story in January marking the 30th anniversary of the Challenger explosion, when he revealed he blamed himself for not being able to convince his bosses at Morton Thiokol or NASA management to wait for warmer weather.
"I think that was one of the mistakes God made," Ebeling told NPR. "He shouldn't have picked me for that job."
The story elicited hundreds of supportive letters and emails in the final weeks of his life. Two of the responses came from former Thiokol executive Robert Lund and former NASA official George Hardy, who both told Ebeling the responsibility was theirs, not his.
"You helped bring my worrisome mind to ease," Ebeling said in his thank you to those who wrote. "You have to have an end to everything."
Ebeling was a rocket engineer at Morton Thiokol in 1986 and called his boss at the company when he found out NASA intended to launch the space shuttle Challenger on Jan. 28. The forecast was for unseasonably frigid 18-degree temperatures. Ebeling told him the cold would stiffen the rubber o-rings seals that kept the rocket fuel from leaking from the giant booster rockets. He told him the shuttle would explode.
But executives at Thiokol and NASA overruled the engineers and 73 seconds after launch, Challenger exploded, killing all seven crew members.
Ebeling retired shortly after the Challenger disaster, and devoted himself to the birds at the Bear River Migratory Bird Refuge, a critical rest stop for more than 250 species of migrating birds.
When a major flood did serious damage to the refuge, he organized a massive volunteer restoration effort including donations that funded the five-year project that ultimately saved the refuge.
Bob Ebeling is survived by wife Darlene and four generations of descendants.