NASA is extremely unlikely to build a new space shuttle to replace Columbia, according to experts, leaving the space agency with the three remaining orbiters as its entire fleet for the foreseeable future.
The next generation of reusable space vehicles is at least 10 to 15 years off, said Donald H. Emero, who served as the shuttle's chief engineer from 1989 to 1993.
"I think the country will not invest in any more shuttles," Emero said Saturday.
Until a few years ago, NASA was exploring several designs for vehicles to replace the space shuttle. But NASA's new administrator, Sean O'Keefe, has shelved those designs and committed to operating the space shuttle for the next 10 to 15 years. The fleet's primary mission during that period will be constructing and servicing the international space station.
Discovery, the oldest of NASA's three remaining shuttles, has been in service for 18 years. Endeavour, built at a cost of about $2 billion to replace the Challenger after that spacecraft exploded shortly after takeoff in 1986, has been flying for a decade. Atlantis, the third remaining shuttle, has been in use for 17 years.
There is no doubt that the remaining space shuttles will be grounded for some time pending NASA's investigation of the Columbia accident.
The next shuttle mission on NASA's flight schedule is a March 1 trip to the space station.