Updated

A faulty part in the steering system for NASA's new Ares I-X rocket has delayed the booster's trek to its Florida launch pad by at least a day as engineers work to fix the glitch.

The rocket, a suborbital version of NASA's new Ares I booster designed to launch astronauts into orbit and ultimately back to the moon, was slated to roll out to Launch Pad 39B at the Kennedy Space Center Monday for a planned Oct. 27 test launch. But a malfunctioning hydraulics component at the base of the towering, 327-foot (100-meter) tall rocket has stalled that plan, NASA spokesperson George Diller told SPACE.com.

"It's at least a day [of delay], but it's still kind of a developing story," Diller said. "We'll have to see how things go for us."

It is not yet clear if the glitch could threaten the Ares I-X launch date, which NASA moved up from an Oct. 31 target earlier this month since work crews were ahead of schedule. Engineers are expected to replace the faulty component, called a hydraulic accumulator, on the aft skirt of the Ares I-X rocket's first stage and test its replacement over the next day or so, Diller said.

"It's associated with the steering and stabilization of the rocket during flight," Diller said of the faulty hardware. A similar glitch occurred on one of the solid rocket boosters for NASA's STS-117 shuttle mission in 2007 and also required repairs, he added.

NASA's Ares I-X rocket is a demonstration version of the full, two-stage Ares I booster, which NASA plans to use to launch its Orion spacecraft — a capsule-based vehicle slated to replace the agency's aging space shuttle fleet. NASA's three space shuttles — Discovery, Atlantis and Endeavour — are due to retire once the International Space Station is completed in the next year or so.

The Ares I uses a giant, five-segment solid rocket booster for its first stage that is similar to the four-segment versions used to help launch NASA shuttles. It is built to be reusable and parachute back to Earth to be recovered in the Atlantic Ocean after liftoff. The second stage is liquid-fueled and not reusable and is designed to ferry its Orion capsule to orbit.

For the Ares I-X launch, NASA will fly a four-segment first stage that includes a dummy fifth segment. The booster's second stage, Orion capsule and launch abort system are all mock-ups and will be dumped into the ocean after stage separation just over two minutes into the flight. Mission managers have said the flight will demonstrate the Ares I rocket concept and shakedown ground preparations procedures.

Currently, NASA only has two days — Oct. 27 and Oct. 28 — and try to launch the Ares I-X mission before standing down due to the unavailability of the Eastern Range it shares for launches with the nearby Cape Canaveral Air Force Station and United States military.

Diller said that it may be possible to delay the Ares I-X rocket's rollout to Pad 39B by one day and still make the Oct. 27 target. But any more delays could prove problematic.

"But it's still too early to tell," Diller said.