A Russian spaceship carrying two Russian cosmonauts and a US astronaut made a belated arrival at the International Space Station yesterday, returning the orbital outpost to full staff.

Russian cosmonauts Alexander Skvortsov and Oleg Artemyev and NASA astronaut Steven Swanson blasted off aboard a Russian Soyuz rocket two days ago from the Baikonur Cosmodrome in Kazakhstan.

They had expected to reach the station, a $100 billion research complex that flies about 250 miles (400 km) above Earth, six hours later.

But about two hours after launch, the crew's Soyuz capsule failed to fire its manoeuvring engines as planned, forcing a delay to the next station docking opportunity on Thursday.

The cause of the skipped rocket firing remains under investigation, said NASA mission commentator Rob Navias.

Preliminary analysis shows the spaceship was 1 degree out of alignment from its predicted orientation, triggering the Soyuz computers to automatically abort the engine burn, Navias said during a NASA Television broadcast of the docking.

Since Tuesday's mishap, the Soyuz successfully conducted the necessary engine firings to reach the station.

"Better late than never," said Navias as the Soyuz made its final approach to the outpost.

The crew's prolonged journey ended at 7:53 p.m. EDT (2353 GMT) as the Soyuz slipped into a berthing port on the station's Poisk module.

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