The launch of Orbital Sciences Corporation's Antares rocket was scrubbed Wednesday afternoon after an umbilical cord to the rocket's second stage detached prematurely.
Umbilical cords typically supply power and allow flight controllers to monitor a rocket's systems until shortly before launch, when these functions are transferred to the rocket's internal control systems.
The cord dropped from its connector about 12 minutes before the main engines were to ignite. The ground team must drain the fuel tanks before technicians can reach the rocket and pinpoint the cause of the failure.
The mission has been billed as a test flight. It aims to iron out any wrinkles in the processes and hardware used at the pad, in addition to demonstrating that the rocket can deliver a payload to orbit. In this case, the payload is a full-size, full-weight mock-up of the cargo carrier Orbital Sciences has designed to carry cargo.
"You learn a little bit form every launch attempt. So we'll take the lessons learned today and move into another launch attempt as soon as it's safe to do so," said John Steinmeyer, a senior project manager at Orbital Sciences.
The test represents a milestone Orbital Science must clear under its $1.9 billion contract with NASA for eight cargo missions through 2015. Successful completion of this mission represents an immediate check for $4 million from the agency, whose payouts to this point depend on the company passing specified milestones.
In all, Mr. Steinmeyer says, the contract with NASA represents "the most ambitious collaboration to date" for the company, which has been building and launching satellites and smaller rockets for more than 30 years.
The launch site, dubbed the the Mid Atlantic Regional Spaceport, is run by the Virginia Commonwealth Spaceflight Authority, a collaboration between Virginia and Maryland.
The spaceport was established in 1997 at the southern end of NASA's Wallops Island Flight Facility. Participants broke ground on Antares's launch pad in June 2009.
Until now, rockets launched from Wallops Island have tended to be suborbital sounding rockets, whose motors burn solid fuel. Antares' installation required pumps, plumbing, and tank farm needed to store and deliver the chilled liquid fuel that Antares's main engines require.
The launch window for this test extends through April 21. If troubleshooting goes well, Orbital Sciences could try again as soon as Friday.