By Kim Tong-hyung
Staff Reporter
South Korea's very first space launch was rescheduled for Aug. 25, after software flaws forced a halt of the countdown at the Naro Space Center in Goheung, South Jeolla Province, Wednesday.
The current ``launch window'' for the two-stage Korea Space Launch Vehicle 1 (KSLV-1) rocket extends until Aug. 26. Moving the blastoff to the current deadline would have meant risking the launch in the typhoon-affected month of September, since the country is required to report to international aviation and maritime authorities at least eight days prior to the launch.
``As it was on Tuesday, the launch on Aug. 25 is expected to be at around 5 p.m., but that of course could be changed according to weather conditions at the time,'' said Kim Jung-hyun, vice science minister, in a news conference in Seoul, Friday.
``We anticipate favorable weather conditions for Aug. 25. Of course this is all part of the process that requires patience. Should another problem be discovered in the countdown Tuesday, the launch could be stopped again.''
The rocket will be moved back to the launch pad on Sunday and a technical rehearsal will be conducted Tuesday to check the rocket's machinery, electronic systems and launch pad functions.
KARI officials plan to fire up the rocket anytime between 4:40 p.m. and 6:20 p.m. to allow the satellite to deploy its solar panels and generate a sufficient amount of energy.
Kim said that the state funeral for the late former President Kim Dae-jung, which is planned for Monday, wasn't a factor in the decision.
The successful launch of the KSLV-1, a 33-meter, 140-ton rocket that is commissioned to deliver a 100-kilogram research satellite into orbit, would make Korea the 10th country to send a spacecraft into orbit from its own soil. The KSLV-1 first stage, containing the rocket engine and a liquid-fuel propulsion system, was developed by Russia's Khrunichev State Space Science and Production Center, which is providing technology for the project.
The second stage of the rocket was developed by the Korea Aerospace Research Institute (KARI), the country's space agency.
After aborting from blastoff with less than eight minutes left in the countdown, the KSLV-1 was defueled and moved to the assembly complex where a team of KARI and Khrunichev Center engineers fixed and analyzed the software problems, Kim said.
Neither Kim nor KARI President Lee Ju-jin, who was present at the news conference, was willing to discuss the exact nature of the glitch.
According to KARI officials, the software in question misinterpreted the data in one of the helium-filled high-pressure tanks that regulates some valves inside the rocket. The software read that the helium pressure was too low, and this caused the automated launch sequence to shutdown, they said.
However, some rocket experts who spoke to the Korea Times said that it is hard to imagine there was anything wrong with the software itself.
More likely is that the pressure within the helium tank dropped lower during the actual launch than what was shown during the previous tests on the ground test vehicle (GTV), a KSLV-1 mockup the Russians made for testing purposes, the experts said.
Lee refused to discuss this possibility, making a beeline out of the newsroom after Kim finished his question-and-answer session.
``All in all, there seems to be nothing seriously wrong with the rocket. If the helium pressure dropped to abnormal levels, there is no way we would be pushing through with the launch, as the results would be disastrous,'' said Tahk Min-jea, a KAIST (Korea Advanced Institute of Science and Technology) rocket scientist who worked as an advisor for the KSLV-1 project.
``It is likely that the software designer set the conditions conservatively. For example, he could have set the variation range between 90 to 110, based on the data from the GTV tests, when 80 to 120 would have been perfectly acceptable to pull off the launch. In this case, the countdown sequence shuts down when the number reaches 89.
``If this really was the case, then I think KARI made a mistake in announcing the problem as a software flaw,'' he said.