“Allan J. McDonald, an engineer who on a chilly January morning in 1986 tried to stop the launch of the Challenger space shuttle, citing the possible effect of the cold on its booster rockets, and who, after it broke apart on liftoff, blew the whistle when government officials tried to cover up his dissent, died on Saturday in Ogden, Utah. He was 83.
The cause was complications of a recent fall, his daughter Meghan McDonald Goggin said.
Mr. McDonald was a 26-year veteran at Morton Thiokol, the contractor responsible for the shuttle’s booster rockets, when he arrived at the Kennedy Space Center in Florida a few days before Jan. 28, when the Challenger was to take off.
The mission was to be the first to carry a civilian into space, a teacher named Christa McAuliffe. President Ronald Reagan was planning to mark that milestone in his State of the Union address, coincidentally scheduled for the same day as the launch.
But Mr. McDonald, who ran the company’s booster-rocket program, had strong reservations about moving ahead with the launch. The shuttle’s rockets contained a series of rubber O-ring gaskets, and he worried that low temperatures could cause them to stiffen, allowing fuel to escape and potentially causing the rocket to explode.”