The Space Shuttle Columbia launches from Kennedy Space Center January 16, 2003. Click here for a larger view.

Shuttle Fleet Stands Idle As NASA Works to Make Safer

Is the space shuttle unsafe? The space shuttle Challenger exploded shortly after liftoff in 1986, and the shuttle Columbia broke up when it reentered Earth's atmosphere on a mission in 2003. Fourteen astronauts lost their lives in the two accidents.

How can NASA make space shuttle flight safer? The Columbia Accident Investigation Board made 29 recommendations, 15 of which must be completed before the shuttle can return to flight. NASA Administrator Sean O'Keefe told journalists last fall that NASA is using these recommendations as a guide to safely returning to shuttle flight operations. "We have vowed to raise the safety bar even higher by finding additional ways to improve the way we conduct business in all aspects of our work," he said.

The renewed emphasis on safety affects every aspect of every job at NASA. Ron Ernst, an aerospace education specialist at the Goddard Space Flight Center in Maryland, said inspections have never been more thorough. "Every tile on the shuttle–and there are more than 23,000 tiles–must be inspected by hand," Ernst said. Any tile replacements must be done by hand. Each shuttle contains thousands of miles of wiring that must be inspected as well.

Workers in the Orbiter Processing Facility check the placement of the reinforced carbon-carbon (RCC) chin panel on Discovery. The chin panel is the smile-shaped section of RCC directly below the nose cap that provides a thermal barrier during reentry. Click here for a larger view.

NASA also is putting into place stricter protocols for astronaut missions, Ernst said. "For instance, NASA will most likely not send another crew to work outside the shuttle on the Hubble Space Telescope," he said. NASA has conducted several missions in which the astronauts on the shuttle have captured the telescope and serviced it to full capacity. As a result, Hubble has provided remarkable new views of the universe.

"We did it, at a high risk to our astronauts," Ernst said. "Now we're looking back on tasks like that and looking at the possible use of robotics."  

Some believe the shuttle is getting to the point of outliving its usefulness. "The first shuttle flew in 1981, so we're 23 years old. It's old technology," Ernst said. "It's still useful, and commercial airlines are flying planes that are older than that and doing well, but it's old technology." The vehicles were designed to make 100 flights, with a turnaround time between flights of 90 days. Most will not make it to 100 flights, Ernst said, and the turnaround time is at least double the 90 days that had been anticipated, especially in view of the new safety requirements.

NASA and the astronauts like the space shuttle because of its tremendous hauling capacity. The shuttle is the only U.S. vehicle that can launch up to eight humans and payloads of 60,000 pounds into space and safely return them from an Earth orbit.  

Workers install Discovery’s cargo bay wiring that will support the addition of an Orbiter Boom Sensor System - one of the new safety measures for return to flight, equipping the shuttle with cameras and laser systems to inspect the shuttle’s thermal protection system while in space. Click here for a larger view.

"It is a tremendous delivery truck for us," Ernst said. "You can put something 50 feet long and 12 feet in diameter in the cargo bay. It's big enough to hold a Greyhound bus in the back. You don't get the sense of how big the shuttle is until you stand under it. It's awesome."

The most compelling reason that the shuttle isn't yet ready to be retired is that NASA has not yet come up with a replacement vehicle. "We're in the development stages of a new multifunctional spacecraft that will take us to the space station and to the moon," Ernst said. "The shuttle is nothing more than a shuttle bus to get us to and from the space station."    

Ernst anticipates the shuttles will complete 15 or 20 more missions to complete construction of the International Space Station. Is he concerned about safety for those missions?

"I think the shuttle is a safe vehicle. I'd fly it in a second," he said. "I'm just waiting for the phone to ring." In his position as an education specialist, Ernst has had the opportunity to work on the shuttle flight simulator. "I'm OK as long as I don't have to land it."

Most important, he said, is the fact that the astronauts believe in the safety protocols for the space shuttle. "Our astronauts have a tremendous confidence in the spacecraft. Their confidence level in what NASA flies and how it flies it is the highest. I have spent time with the astronauts. They put their lives on the line, and they are confident that what NASA does and their skills together will get through the mission and back to Earth safely."