WASHINGTON — The terrifying landing Saturday of a Russian space capsule with three astronauts aboard is raising serious concerns about how to get humans to and from the International Space Station.
The Russian Soyuz transport vehicle dropped into a burning field of grass, 240 miles off course, in Kazakhstan. The crew, shaken but unhurt, saw flames approaching when they opened the spaceship's hatch. They slammed the door shut, but their landing parachute burned up before local farmers helped them out.
Before the parachute opened, the capsule "came down like a bullet out of a rifle," William Gerstenmaier, NASA's associate administrator for space operations, told the House of Representatives space subcommittee on Thursday. The crew was squeezed by gravity forces 8.2 times greater than on Earth.
This was the second time that the Soyuz landing capsule — the part that carried the crew, which included an American astronaut — failed to separate from its power module when it left the orbiting space station. That failure put the capsule in free-fall, instead of a controlled glide to earth, with its precious heat shield facing the wrong way. The cause of the malfunction hasn't been identified.
"The fact that the same problem occurred in two vehicles is a cause for concern," Gerstenmaier said. "The Russians are as concerned as we are. Before we use Soyuz again, we need to understand the problem."
The near-disaster dramatized NASA's need to find a way to ferry people and cargo to the space station after the last U.S. space shuttle flight is completed in 2010. NASA intends to replace the shuttle with its new manned spacecraft, Orion, but Orion won't be ready until 2016 at the earliest.
The six-year gap will have to be filled by Russian, European or Japanese spaceships, but only Russia's Soyuz is capable of carrying people. Another option, American-made commercial spacecraft, won't be ready to carry cargo for at least two years and astronauts for at least four years.
"NASA is well aware of the predicament it faces," said Cristina Chaplain, a procurement expert at the Government Accountability Office, a congressional investigating agency. "Orion may not meet its 2016 target."
The space station is supposed to be completed in 2010, but it would be only a huge, expensive piece of space junk if it cannot be supplied with people and cargo.
"After assembly is complete and the shuttle retires, NASA's ability to rotate crews and supply the ISS will be impaired," Chaplain told the subcommittee. The Russian, European and Japanese vehicles were "designed to augment the capabilities of the shuttle, not replace them, and have far less capacity to haul cargo," she said.
Subcommittee members worried that the $100 billion or more that already has been spent on the space station would be wasted, especially since there are as yet no plans to continue using the massive facility after 2016.
"It's ridiculous to think of decommissioning the station before we've even finished it," said Louis Stodieck, director of BioServe Space Technologies, an aerospace firm in Boulder, Colo. "We need it to go at least until 2020."
The astronauts who escaped their brush with death last weekend were two women, American Peggy Whitson and South Korean Yi So-yeon, and a Russian man, Yuri Malenchenko.
"At first I was really scared because it looked really, really hot, and I thought we could burn," Yi told a news conference in Star City, Kazakhstan, after the descent.
Whitson said the descent was "pretty, pretty dramatic. Gravity's not really my friend right now."