The next shuttle flight could occur in December. Photo: NASA

NASA expects to announce its shuttle return to flight plans soon after the Columbia Accident Investigation Board reports this summer and could realistically resume missions as early as December, a senior space agency official said Wednesday.

"Clearly within a month I think we are going to have a Gehman board result," Michael C. Kostelnik, NASA's deputy associate administrator for international space station and shuttle programs, told reporters in Florida. "We are committed on the NASA-side to have our return to flight plan as a matter of record out in the open fairly quickly after that and we will have in that a very specific planning window for the flight."

NASA officials currently believe they can resume shuttle flights and the assembly of the international space station as soon as December, and certainly by early next year. That would require implementing the recommendations of the investigation board, including redesigning the external fuel tank bi-pod ramp, which was the source of the insulating foam that hit Columbia's left wing during launch and is believed to have doomed the shuttle.

Michael Kostelnik. Photo: NASA

"We can clearly put this together and return to this mission in the first quarter of '04," Kostelnik said.

Initially, missions will be restricted to daylight launches so tracking cameras can keep a close watch for any insulating foam that might break away from the shuttle's external fuel tank. Separation of the spent fuel tank will also occur in daylight allowing astronauts to photograph it and record any unexpected foam loss.

That, combined with long-standing orbital lighting restrictions for the space station, known as beta-angle cutout periods, will limit the number of launch opportunities. In December it would be possible to launch only on the 18th or 19th and that would also require a change in the space station's altitude. In January, February and March there would be multiple opportunities to fly, Kostelnik said.

Once the agency is sure the foam problem has been fixed, night launches could resume, opening up many more launch windows, Kostelnik said.

The most pressing need to resume shuttle flight is to restock the space station's dwindling food and water supplies. The station's water reservoirs are expected to dry up early next year, Kostelnik said.

"The farther you go beyond that, the more problematic it starts to get, so the more important return to flight and its dates are."

Spare parts are also a major consideration. NASA officials consider themselves lucky that no serious equipment problems have required spare parts to be shipped to the station. Some replaceable units are too big to fit about Russia's Progress cargo ships and even smaller spares can take up valuable space needed for food and water.