South Korea on Friday delayed the launch of a small satellite launch vehicle after detecting a leak in the fueling system for the rocket's Russian first stage, according to media reports.

Photo of the KSLV rolling to the launch pad on Wednesday. Credit: Khrunichev
 
The Korea Satellite Launch Vehicle, or KSLV 1, was being prepared for liftoff Friday from the Naro Space Center, a facility about 300 miles south of Seoul.

The 108-foot-tall rocket was aiming for its third try to loft a small satellite into orbit after two identical launchers failed in flights in 2009 and 2010.

According to the Yonhap news agency, engineers will remove the two-stage rocket from the launch pad to replace a seal, delaying the launch at least three days.

The KSLV's first stage is built by Khrunichev, a major Russian aerospace contractor. Its RD-151 main engine burns kerosene and liquid oxygen propellants.

The leak was detected at the interface between the first stage and the launch pad's fueling system during standard prelaunch checks before the KSLV's launch window, which extended from 0630 GMT to 1000 GMT (2:30-6:00 a.m. EDT), or 3:30 p.m. to 7 p.m. local time.

Because the rocket must be moved from the launch pad to fix the problem, launch will be pushed back at least three days, according to Cho Yul-Rae, South Korea's vice minister of education, science and technology.

"If the problem is easily fixed, it could take three days from now to launch the rocket. But if the problem is more complicated than we currently suspect, it might take more time," said an official quoted by Yonhap.

The part-Russian, part-Korean KSLV is part of a $471 million rocket development program. South Korea builds the vehicle's solid-fueled second stage and payload fairing, while Russia provides the first stage under a contract signed in 2004.