Broadcast: Mar 15, 2003

The U.S. space agency NASA is getting ready to resume shuttle flights as early as September or October. But the return to flight depends on whether the cause of the shuttle Columbia's ¹⁾demise can be found and fixed.

NASA is planning to assemble a team to get U.S. space shuttles ready to return to flight by the final quarter of this year.

That plan was revealed in an internal ²⁾memorandum written Wednesday by the agency's top space flight official, former astronaut William Readdy. NASA made the document public Friday.

In it, Mr. Readdy says a team will prepare to return shuttles to flight as soon as practicable. He makes clear, however, that the schedule depends on findings of an independent board of experts investigating the cause of Columbia's break-up last month. But he sets the goal for the next shuttle mission as early as this coming fall in the United States, beginning in September.

NASA spokesman Joseph Gordon points out that the schedule only suggests the earliest time a shuttle might fly again. "It's just that in this business you have to have a goal," he said. "For practical purposes at this time, no earlier than the fall date or timeframe seems practical. Most likely, it'll be probably later than that - hopefully not much later. But, again, it's all dependent upon the results of the board and on us reacting to those results."

Should a shuttle return to flight late this year, the break would be far shorter than the 32 month moratorium after the 1986 explosion of the Challenger vehicle. But the need to get shuttles back to orbit is more urgent now because they are essential to support the International Space Station.

The next shuttle mission was supposed to be later this month, a mission to exchange station crews.

But as a result of the Columbia disaster, the crew swap will take place in late April or early May, using Russian Soyuz rockets. The three-man U.S. and Russian team now in orbit will return to Earth aboard the Soyuz attached to the station as an emergency escape vehicle. Before their departure, another Soyuz will carry up a two-person replacement crew.

Station commander Ken Bowersox says that, despite the Columbia tragedy, he is not nervous about re-entering the atmosphere. "Entry in any vehicle is always a big deal," he explained. "You are taking a lot of kinetic energy and removing it from a system. That all gets turned into heat. It's a time that's fraught with danger and you need to be careful about everything that goes on during that period. But I wouldn't say that I feel any more apprehension now than many other entries that I've been through."

Although Commander Bowersox and his two colleagues had not expected to return on a Soyuz, they trained on one in Russia as part of routine preparations for an emergency escape from the outpost. They will enter the Soyuz over the weekend to practice the departure procedures.

David McAlary VOA news, Washington.

1）demise [di5maiz]n.死亡,消灭，停止活动

2）memorandum[7memE5rAndEm]n. 备忘录, 便笺, 便函