Why did South Korea's rocket launch fail?

South Korean officials said they did not know where to pin blame, but noted the explosion occurred in the Russian-made first-stage of the rocket rather than in the Korean-made second stage. The failure of the South Korea rocket launch was an embarrassing setback.

The South Korea Space Launch Vehicle takes off from the launch pad at the Naro Space Center in Goheung, South Korea, Thursday, June 10, 2010. South Korea launched the rocket carrying a satellite meant to study climate change Thursday, but the rocket exploded just minutes into the flight.

AP Photo/ Korea Pool

June 11, 2010

South Korean and Russian scientists sought explanations Friday for the explosion of a rocket that sent a Korean satellite into the sea within less than 2-1/2 minutes in an embarrassing failure for South Korea’s costly space program.

Officially, South Korean officials said they did not know where to pin the blame, but noted that the explosion occurred in the Russian-made first-stage of the rocket rather than in the Korean-made second stage. Korea’s highly ballyhooed first attempt at launching a satellite from Korean soil has been a joint project in which Russia's Khrunichev Space Center built the liquid-fueled first stage while the Korea Aerospace Research Institute built the solid-fuel second stage.

The explosion occurred “before the first and second stage,” said a member of the Korean team at the Naro Space Center from which the rocket was launched Thursday. “That’s in the timeline.” The launch came after a one-day delay caused by a glitch in a fire-control system not related to either the rocket or the satellite.

Korean national pride over the idea of firing a satellite into space is obvious from the name Koreans gave it: KSLV-1, or Korea Space Launch Vehicle-1. While the name no doubt will endure in another attempt, the sense of sadness over the failure is tangible among all those involved in the project.

The failure of the rocket was particularly painful for Korean officials beleaguered by public criticism for focusing on costly projects and favoring large business interests while ignoring the needs of ordinary people. The conservative government of President Lee Myung-bak suffered a setback in local elections on June 2 in which opposition candidates won a majority of the races for governor and mayor.

“They rushed too much,” says an office manager, Kim Myung-sun. “They were under too much pressure. It was because of the money.”

$1 billion program

Such suspicions are widespread in view of the cost of a program that has cost nearly $1 billion all told as a result of years of research culminating first in the failure of the launch of a similar satellite last August and then the one on Thursday. Now Korean officials are saying the Russians will have to pay for a third attempt even though the Khrunichev Space Center is not expected to want to take full responsibility.

South Korean Minister of Education, Science andTechnology Ahn Byong-man cited wording in the agreement with the Russians for the third launch if the first two launches did not put the 100-kilogram satellite into orbit. The satellite, from a relatively low height of 600 kilometers above the earth, was equipped to analyze and forecast weather patterns.

A South Korean official described the mood at the Naro Space Center as “very sad” after a failure that was even worse than the one last August. Russian and South Korean teams of more than 100 scientists and engineers from each country got the word, said Mr. Ahn, after “an inboard camera detected a bright flash of light at 137 seconds into the flight.” The light flash, he said, “coincides exactly with the loss of communication with the two-stage rocket.”

South Korean Navy vessels were picking up bits of debris where the pieces of the rocket and satellite hurtled into the Pacific Ocean about 290 miles south of the southernmost Korean island of Jeju. The rocket with its payload was about 40 miles above the surface at the time of the failure.

Less successful this time

The news was all the more disheartening since this attempt was actually less successful than the one in August. The satellite at that time was just going into orbit at the moment of an explosion 225 seconds after liftoff. The Khrunichev Space Center disavowed responsibility, blaming the separation of the payload from the rocket’s second stage, all built by the Koreans.

At the Korea Advanced Institute of Science and Technology in Daejeon, south of Seoul, veteran aerospace engineer Park Chul, offers a simple explanation for the failure.

“It blew up during combustion of the first-stage rocket,” says Mr. Park, who spent 37 years as an engineer with NASA in the United States. “That’s what we call ‘knocking’ in our car engine. In a rocket, the engineering term is detonation. You must prevent this from happening.”

Park says the chances of failure become worse “if you make a rocket engine of higher performance.” The engine for the first stage was in this case supposed to offer “10 percent better performance” than any other.

“This engine has the highest possible pressure,” he says. “At that pressure, the danger is greater.”

The launch of a satellite from Korean soil was seen as a pivotal event for a nation that prides itself on having launched satellites from other countries, including Russia. The European Space Agency is to launch Korea’s first geostationary satellite later this month from a center in French Guiana. That satellite will remain in a stationary orbit 35,000 kilometers above the earth gathering material for meteorological purposes.

“We have our own satellites,” says Lee Tok-ju, another former NASA engineer who heads the department of space engineering at the Korea Advanced Institute of Science and Technology. “The space launcher is much more difficult.”

Mr. Lee calls Russia “No. 1 in space launchers,” but say the Russians insisted on designing the entire first stage of the launcher rather than cooperating with Koreans. “They don’t want to reveal their secrets,” he says.

Park says the Koreans turned to Russia after having failed to develop their own launch vehicles successfully with smaller engines. “They kept blowing up,” he says. “Politicians and the public wanted results.”

The Americans were no longer building rockets, much less sharing technology, says Park, and had already fallen far behind.

“So the Koreans went to Russia and asked the Russians to build an engine,” says Park. ”The Russians “refused to sell any existing engine but said they will spend the money to develop a new powerful engine.”

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