William R. Lucas, who oversaw development of rockets for the National Aeronautics and Space Administration and shouldered much of the institutional blame for the catastrophic explosion that killed all seven astronauts aboard the Challenger space shuttle in 1986, died on Feb. 10 at his home in Huntsville, Ala. He was 102.

His family confirmed the death.

Dr. Lucas was described as a strong-willed, even autocratic director of the Marshall Space Flight Center in Huntsville, which supervised the design and building of the booster rocket whose failure caused the fatal breakup of the Challenger in Florida just 73 seconds after liftoff.

The sickening explosion, on a clear and cold January morning, was witnessed by children in classrooms across the country because the crew included Christa McAuliffe, a New Hampshire schoolteacher who was to be the first American civilian in space.

Investigators determined that the accident was caused by the failure of a rubber seal, known as an O-ring, on one of two booster rockets, which were attached to the shuttle like a jetpack to propel it skyward.

The night before the launch, Dr. Lucas was told that engineers were insisting that the mission be delayed because of cold weather, which they feared would cause the O-rings to fail and leak combustible gasses.