NEW YORK: SpaceX, the rocket company of high-tech entrepreneur Elon Musk, was due on Sunday to launch four astronauts on a flight to the International Space Station, NASA's first full-fledged mission sending a crew into orbit aboard a privately owned spacecraft.

The company's newly designed Crew Dragon capsule, which the crew has dubbed Resilience, was set for liftoff atop a SpaceX Falcon 9 rocket at 7:27 p.m. Eastern time (0027 GMT on Monday) from NASA's Kennedy Space Center in Cape Canaveral, Florida.

The 27-hour ride to the space station, an orbiting laboratory some 250 miles (400 km) above Earth, was originally scheduled to begin on Saturday.

But the launch was postponed for a day due to forecasts of gusty winds - remnants of Tropical Storm Eta - that would have made a return landing for the Falcon 9's reusable booster stage difficult, NASA officials said.

NASA is calling the flight its first "operational" mission for a rocket and crew-vehicle system that was 10 years in the making. It represents a new era of commercially developed spacecraft - owned and operated by a private entity rather than NASA - for sending Americans into orbit.

"This is the culmination of years of work and effort from a lot of people, and a lot of time," Benji Reed, SpaceX senior director of human spaceflight programs, told reporters on Friday. "We have built what I would call one of the safest launch vehicles and spacecraft ever."

A trial flight of the SpaceX Crew Dragon in August, carrying just two astronauts to and from the space station, marked NASA's first human space mission to be launched from U.S. soil in nine years, following the end of the space shuttle program in 2011.

In the intervening years, U.S. astronauts have had to hitch rides into orbit aboard Russia's Soyuz spacecraft.