WALLOPS ISLAND, Va. (AP) - A private company contracted by NASA to make supply runs to the International Space Station scrubbed a Wednesday test launch of an unmanned rocket, saying a cord linked to the rocket's second stage apparently detached too soon in blustery winds.
The towering Antares rocket had been scheduled to blast off Wednesday afternoon from Wallops Island on Virginia's Eastern Shore when the countdown clock was halted 12 minutes before a 5 p.m. launch window was to open.
Barron Beneski, a spokesman for Dulles-based Orbital Sciences Corp., said officials initially suspected a premature separation of the cabling from the launch pad to the second stage of the rocket. He said experts were investigating exactly what happened.
Officials said they would try again no sooner than Friday afternoon, though no date was immediately announced.
Earlier in the day, the launch director for NASA's Wallops Flight Facility granted Orbital permission to proceed with a launch as long as winds didn't exceed 23 mph, up from the 17 mph cap that was originally in place.
Orbital officials had said earlier that low clouds hugging the Virginia coast were a concern Wednesday. Officials had already shortened the window for a possible launch from several hours to just 10 minutes Wednesday amid weather concerns.
The planned launch by the Washington area commercial firm was designed to test whether a practice payload could reach orbit and safely separate from the rocket. Orbital executives have said they are conducting the tests as they prove their capability to carry out several supply runs they contracted for with NASA.
Orbital was one of two commercial companies, along with California-based competitor SpaceX, chosen to supply the space station by NASA, which ended its three-decade-old shuttle program in 2011.
SpaceX, based in Hawthorne, Calif., was awarded a $1.6 billion contract by NASA in 2006 to make a dozen restocking missions. SpaceX has linked up with the space station three times, though only two of those deliveries occurred under its resupply contract. Its Dragon capsule is the only supply ship capable of two-way delivery
In 2008, Orbital jumped in and was awarded a $1.9 billion contract for eight deliveries.
"We've been playing catch up, but we're about caught up," said Frank Culbertson, executive vice president and general manager of Orbital's Advanced Programs Group, had said recently as test plans loomed. "By the end of next year we should have an additional four or five cargo missions under our belt, so we're going to be moving fast."
If ultimately successful in testing Antares, Orbital executives have said they hoped to launch a rocket this summer carrying its Cygnus cargo ship aloft to see whether it could safely dock with the space station. During such a demonstration flight, the cargo ship would carry about 1,600 pounds of supplies.
Orbital is under contract to deliver about 44,000 pounds of supplies to the space station and plans to make about two deliveries per year. Its cargo ship would carry about 4,400 pounds worth of supplies on its first three missions and 5,600 pounds on its last five.
Unlike the SpaceX's Dragon capsule, the Orbital cargo ship is not designed to return with experiments or other items from the space station. Instead, plans call for filling its Cygnus ship with garbage to be incinerated with the craft upon re-entering Earth's atmosphere. That's also what Russian, European and Japanese cargo ships do.
Brock Vergakis can be reached at www.twitter.com/BrockVergakis