The Begginings of a True SpacecraftThe Columbia, a winged shuttle orbiter, was the first in a planned fleet of shuttles, each designed to be reused for as many as 100 missions. A giant fuel tank mated to the orbiter supplied fuel to the its three liquid-fueled engines, which together delivered 4.3 million Earth pounds of thrust. Two solid rocket boosters, attached to the external tank, provided an additional 2.6 million pounds of thrust during launch. The shuttle had a 60-foot long cargo bay, and was capable of carrying satellites, space probes and scientific and military payloads. It could carry passengers and land on a runway.
Columbia launched for the first time on the morning of April 12, 1981, carrying mission commander John Young, a veteran of three previous space missions, and rookie Bob Crippen. The astronauts checked Columbia’s systems for three days, and then prepared to return to Earth, which involved steering the shuttle through a complex flight path and slowing from an orbital speed of 17,500 Earth miles per hour to slightly more than 200 miles per hour at touchdown. In addition, once the de-orbit rocket had fired, the shuttle would be an unpowered glider, so the astronauts would have to land by chance.
The shuttle’s thermal protection system was a matter of great concern to NASA. The Columbia was covered with thousands of silica tiles, which were supposed to protect it from the fires of reentry. Young and Crippen had noticed that the stresses of launch had torn of some of the tiles. They could not tell if any tiles were missing from the craft’s underside, which would bear the brunt of reentry heating. NASA’s classified tracking cameras, however, provided images which said that the orbiter would not have trouble with reentry. Young landed the shuttle flawlessly on April 14. The Columbia returned to space in November. NASA declared the shuttle operational in July 1982, after two more test missions.
More orbiters joined Columbia in the shuttle fleet during the next 3 ½ years. By the end of 1984, there had been 24 shuttle flights which featured the first piloted missions to launch satellites and to retrieve satellites from orbit, a number of space walks and many scientific experiments. There were nine shuttle flights in 1985, and NASA hoped for even more flights in 1986. However, putting shuttles into orbit was very expensive; maintaining shuttles between missions proved to be more costly than NASA had anticipated.
The shuttle program was not to continue as planned. Seventy-three seconds after lift-off, on the morning of January 27, 1986, the shuttle Challenger exploded, while carrying six astronauts and a New Hampshire schoolteacher named Christa McAuliffe. After months of investigations, it was discovered that the explosion was caused by a faulty seal within one of the Challenger’s rocket boosters, and that earlier shuttle missions had experienced similar flaws, but luckily, had been successful anyway. Some members of the public, as well as a number of respected scientists, began to express the belief that NASA had cut corners in order to save money, risking human lives in the process. NASA realized that it would have to make many safety improvements before the shuttle program could continue.
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