NASA Presents New Space Taxi Designs

Sept. 29, 2003 -- The next-generation space vehicle is on the drawing boards now and NASA has just issued newly defined requirements.

The designers who built the Space Shuttle back in the 1970s probably thought the orbiters would be in a museum by now. No one expected shuttles to still be flying in the year 2003. The remaining three shuttles — Atlantis, Discovery, and Endeavour — will be the backbone of the American space program for another decade, perhaps longer.

The breakup of the shuttle Columbia over Texas on February 1 depleted NASA's already limited ability to transport crews and cargo into space. And there is little chance this will improve soon since all shuttles remain grounded until NASA implements the recommendations of the Columbia Accident Investigation Board (CAIB).

‘Lifeboat’ Limits Crew

The lack of shuttle support is a problem for the crew members aboard the International Space Station, who are now dependent on the Russian Progress and the Soyuz space vehicles for supplies. A Soyuz craft is always docked at the ISS as an emergency escape system if needed. And since the Soyuz can only carry three astronauts, the ISS can only be staffed by a maximum three-person crew until another escape option is available.

The lack of a next-generation space vehicle was noted in the CAIB report on the Columbia accident,which chastised NASA and those who make space policy in this country for being shortsighted.

"Because of the risks inherent in the original design of the Space Shuttle, because that design was based in many aspects on now obsolete technologies, and because the Shuttle is now an aging system but still developmental in character, it is in the nation's interest to replace the Shuttle as soon as possible as the primary means for transporting humans to and from Earth orbit," the authors wrote.

For now, NASA would like to supplement the shuttle with a simpler craft: An Orbital Space Plane that would ferry astronauts and some cargo to the International Space Station, and also serve as a "lifeboat" on the ISS.

Four Designs

There are four concepts under consideration for the Orbital Space Plane, though the final result may not look like an airplane at all. The possibilities include a capsule, similar to the Apollo series that splashed into the ocean during landing, a rounded, half-cone lifting body that could be recovered on an airfield after landing, a sharp body with wings and a blunt body with wings, both of which would touch down as aircraft.

All four concept vehicles would launch on an expendable launch rocket, then dock with the International Space Station and land back on Earth.

The Orbital Space Plane may end up resembling a shuttle, but the similarities will end there. The OSP won't be a truck in space, it will be more like a taxi, carrying crew back and forth and serving as a rescue vehicle if something goes wrong on the space station. Two versions of the Orbital Space Planes will be built: one to be used as a rescue vehicle, the other to be used to ferry crews back and forth of the space station and to carry light cargo.

"The vehicles would be almost identical," said Dennis Smith, the OSP Program Manager for NASA. "They might be outfitted differently. It's like a 747, one of them takes passengers, the other one works for FEDEX and takes packages. We are going to develop one design. The only difference between a crew rescue mission and a crew transfer mission is you don't have any crew inside the vehicle on ascent."

Long Overdue

John Junkins, Professor of Aerospace Engineering at Texas A & M University thinks it's about time NASA develops a new space vehicle.

"The Space Shuttle is 25-year-old technology that has not kept up," Junkins said. "But it has done everything asked of it — carry people and carry huge amounts of cargo. No other space vehicle can do that. But it is time to separate the responsibilities."

NASA would like to have the Orbital Space Plane flying by 2008. John Junkins thinks it's possible.

"If we can go from the drawing board to the Moon in 10 years, we can do this in five years," he said.

How much will this next generation vehicle cost? The budget goes first to the White House for approval,then to Congress. The final design will be announced in August 2004.