Moscow  - South Korea's first astronaut confessed Monday she was "very scared" as she smashed back into the atmosphere when the Russian space capsule went off-course on reentry at the weekend.

"I saw flames around the ship and at first I was really scared," said bio-engineer Yi So Yeon. "I thought we were going to burn."

But Yi, 29, said she calmed herself by looking at her colleagues who seemed "cool-headed."

"So I pretended to also be okay," she said back at Star City training centre outside Moscow where she trained for six months.

Yi and the two other International Space Station (ISS) crew members, US astronaut Peggy Whitson and Russian cosmonaut Yuri Malenchenko were subjected to major gravitational pull and a hard impact as the capsule deviated on re-entry.

The automatically piloted craft erred and crashed in what was called a "ballistic landing," 400 kilometres off-target in the desert Kazakh steppes.

The crew shocked local farmers as they climbed out of the cramped aircraft after 192 days in space for Whitson and Malenchenko and nine days for Yi.

"They didn't believe we were from outer space, even after we showed them our space suit," Malenchenko laughed.

The equipage's dramatic appearance apparently left locals puzzling over whether the capsule was a boat or a plane.

Though they helped the strange crew make their location known, local residents refused to believe they had come from outer space until authorities arrived 40 minutes later, Malashenko recounted.

The mission control centre said Monday an investigation was underway into the cause of the misdirection. It is the second year that the Soyuz craft has gone off course on landing though no cosmonauts have been injured.

Malenchenko, 46, and Whitson, 48, had been in space since October 10, 2007, when they blasted off from Kazakhstan's Baikonur Cosmodrome.

Whitson, who took over as the first woman commander, set a new record with a total of 377 days in space, she said Monday.

Yi made history as South Korea's first astronaut when she took off on a mission to the ISS on April 10. South Korea reportedly paid 20 million dollars for her flight.

She arrived at the space station along with the ISS Expedition 17 crew - Sergei Volkov and Oleg Kononenko who will remain in orbit until next autumn. (dpa)