Shuttle problems familiar

last updated 8 January 2015

Houston

NASA engineers were well aware of the technical flaws that combined to doom the space shuttle Columbia, investigators said this week, but convinced themselves they posed no serious risk. Engineers had been trying for three years to come up with ways to keep heat shields on shuttle wings from wearing down or cracking in flight. NASA officials had also worried about foam insulation on fuel tanks, which often broke away and hit shuttles on liftoff. Investigators suspect the two problems together may have weakened Columbia’s wing, which burned up re-entering the atmosphere on Feb. 1. The same pattern—problems that were spotted but not fixed—was blamed for the loss of the shuttle Challenger in 1986, said former astronaut Sally Ride. “I’m hearing a little bit of an echo here.”