A US-Russian crew stranded in space by the Space Shuttle tragedy reached the Kazakh capital Astana on board a Russian helicopter more than eight hours after landing.

They were found alive and well after losing radio contact on re-entry and landing almost 500km off target in the steppes of Kazakhstan.

The Americans Ken Bowersox and Donald Pettit and Russia's Nikolai Budarin had to wait over two hours to be located by anxious rescuers scouring the Central Asian steppes in planes and helicopters. It was not clear why the capsule missed its planned landing site in Kazakhstan.

Officials said Pettit had injured his shoulder. He was laid out on a stretcher in the helicopter and did not greet waiting officials at Astana.