10 June 2010
Naro Rocket Blows up in Midair
Korea demands Russia provide rocket for 3rd launch

By Kim Tong-hyung
Korean Times


The Naro space rocket with the payload of a science satellite lifts off from the launch pad at the space center in Goheung, South Jeolla Province, Thursday evening. At right are three sequential shots taken from footage by television station KBS that show, from top, the rocket exploding. / Korea Times

GOHEUNG, South Jeolla Province ― The second flight of the Korea Space Launch Vehicle I (KSLV-I) ended in failure with an explosion Thursday. The rocket, carrying a satellite aimed at observing the atmosphere and oceans, blasted off from the Naro Space Center here at 5:01 p.m., but exploded about two minutes later.

The spectacular letdown adds to the fears that the country's Herculean investment of money and effort into its first home-launched rocket may never produce the desired returns.

The Naro spaceport lost contact with the rocket 137 seconds after liftoff, when it was believed to be at an altitude of around 70 kilometers, which appears to be the moment when it exploded, according to the Korea Aerospace Research Institute (KARI), the country's space agency.

Sources close to the launch project told The Korea Times that first indications suggest a failure of the rocket's main, RD-151 rocket engine, developed by Russia's NPO Energomash, as its performance was seen to be reduced considerably as the vehicle began to veer off course. The rocket's payload, the Science and Technology Satellite No. 2 (STSAT-2), was also destroyed.

A number experts of also suggested that the country was fortunate to avoid a disaster as ground control was unable to command the wayward rocket to self-destruct with communications being out, which may have led to shuddering consequences had debris crashed onto land.

The doomed KSLV-I launch was the first launch since one in August last year, when the rocket achieved its desired speed and height, but failed to deliver its payload satellite into orbit.

``The Naro (KSLV-1) flew normally until 137.19 seconds after liftoff, when the communications with the ground tracking facilities were severed. The footage from the camera installed on the upper part of the rocket suddenly brightened at that moment, which suggests that the rocket's first stage exploded during flight,'' said Ahn Byung-man, South Korea's minister of education, science and technology, before bustling out of the spaceport's briefing room refusing to respond to questions from hounding media members.

KARI later confirmed that the debris has fallen in the waters off the southern coast of Jeju Island.

Tak Min-jae, a rocket scientist at the Korea Advanced Institute of Science and Technology (KAIST) who worked as an adviser on the KSLV-I project, said it was extremely rare for a rocket to explode after advancing that much into flight.

``Most rocket explosions occur around blastoff, and the rocket seemed to be right on course before the supposed explosion. This could only be explained by a failure of the first stage's main engine,'' Tak said.

``There could be hundreds of reasons why a rocket engine fails, but a possibility could be a malfunctioning turbo pump, which may have pumped in too much fuel into the engine. The flight-termination system is useless when the communications are killed, and you can't blame ground control for failing to command the rocket to self-destruct at an earlier moment when it was moving accordingly with its flight trajectory.''

The part-Russian, part Korean rocket is a result of a 502.5 billion won ($418 million) investment. Russia's Khrunichev State Research and Production Space Center, which is providing the core technologies for the Korean rocket project, designed and developed the KSLV-I first-stage, which holds the rocket engine and liquid-fuel propulsion system.

KARI developed the KSLV-I second-stage, which is designed to hold the satellite and release it into proper position.

Now, with KSLV-I reduced to sea junk after its first two tries, the South Koreans and Russians are expected to engage in an ugly game of finger pointing, which may determine whether the rocket will get another chance at the Naro spaceport or not.

The Russians are under contract to provide at least two launches, and a possible third should their technology related to the KSLV-I first-stage be found responsible for the failure of any of the first two attempts. KARI was guilty for the bungled first launch, but should the explosion of the KSLV-I first stage be confirmed as the reason for Thursday's crash, the Russians could be roped in for a third try sometime next year.

Kim Seung-jo, a Seoul National University (SNU) aerospace scientist who participated in a government panel investigating the failure of the first launch, agreed with KARI's theory that a malfunction of the rocket's first stage engine likely doomed the recent flight.

``The KSLV-I's main telemetry system was installed in the second stage and this was likely damaged by an explosion in the first stage, which explains the communications breakdown. This points to the possibilities of a flawed rocket design or an error during the assembly process,'' he said.

``But nonetheless, the process of agreeing on the cause of the explosion will likely be a very long and frustrating experience.''

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