1. After flying this thing for 22 years, doesn't NASA know how to fly the shuttle?

Shuttle Columbia lifted off for the first time on April 12, 1981 on STS-1. It was the first time two astronauts flew a new U.S. spacecraft on its maiden voyage.

After only three more test flights during the next two years, NASA declared its space transportation system operational, removed the ejection seats from Columbia and began using the shuttle as a one-size-fits-all solution for the nation's commercial, military and scientific needs in space.

With each mission NASA gained more confidence in its ultimate flying machine. Crew sizes quickly grew and satellites were launched, repaired and rescued by spacewalkers buzzing around on jet backpacks.

Then the 1986 Challenger disaster popped NASA's bubble. A presidential investigation panel found fault with the shuttle's technology and NASA's decision making process. It took NASA nearly three years to fix the booster rocket problem and restructure its management.

On Sept. 29, 1988 shuttle Discovery returned America to space. It wasn't long before the shuttle program regained confidence, renewed its status as a symbol of technical superiority and resumed its role as an icon of the American spirit of exploration.

Then on Feb. 1, 2003 Columbia and its crew of seven astronauts was lost.

The Columbia Accident Investigation Board will say that despite the success the shuttle program has enjoyed, NASA has become too familiar with the program, like an old friend whose buddies have overlooked its quirks and flaws. In a word: operational. Instead, NASA must treat each shuttle mission as a test flight.

The board will point out that NASA's historic X-15 rocket plane flew 199 missions from 1959 to 1968 and every mission was considered an extremely dangerous test flight. The shuttle on the other hand has flown 113 times during a 22-year period. In effect, NASA has more experience with the vehicle that led to the shuttle than it does with the shuttle itself.

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