Skip to content
  • KOSPI 3013.13 -15.91 -0.52%
  • KOSDAQ 1001.62 -3.73 -0.37%
  • KOSPI200 393.74 -1.67 -0.42%
  • USD/KRW 1181.7 -4.10 -0.35%
  • JPY100/KRW 1,032.73 -4.67 -0.45%
  • EUR/KRW 1,374.97 -1.80 -0.13%
  • CNH/KRW 184.32 -0.08 -0.04%
View Market Snapshot

Aerospace

S.Korea’s first homegrown space rocket Nuri set for October launch

More than 300 firms have joined hands to support the country's giant leap into space

Aerospace

S.Korea’s first homegrown space rocket Nuri set for October launch

By Oct 08, 2021 (Gmt+09:00)

South Korea will be the seventh country in the world to launch a space rocket with homegrown technologies. The long-awaited Nuri, or Korea Space Launch Vehicle-II (KSLV-II), will be launched into space at 4 p.m. on Oct. 21.

Nuri is a three-stage-to-orbit rocket that the South Korean government and industries have spent more than a decade in its development. The first stage uses a cluster of four 75-ton liquid fuel engines to launch from the ground, while the second stage uses one 75-ton liquid fuel engine. A 7-ton liquid fuel engine is used in the third stage, driving the spacecraft body up to the altitude of its orbit.   

nuri

Third Stage
7-ton Liquid Fuel Engine

Second Stage
75-ton Liquid Fuel Engine

First Stage
4 Clustered 75-ton Liquid Fuel Engines



The liquid fuel, unlike solid fuel used by some other types of space rockets, enables Nuri to switch the engines on and off depending on circumstances. Such an option allows more precise control of the rocket, according to industry experts. All relevant technologies were developed domestically in South Korea.

A TEAM EFFORT INVOLVING MORE THAN 300 KOREAN FIRMS

Nuri, or KSLV-II, is a work of collaboration involving more than 300 different South Korean firms. The figure is almost double that of the number of firms that participated in the development of Naro, or KSLV-I. Naro, unlike Nuri, adopted most of the key technologies from Russia.

The foremost task in developing Nuri was making a homegrown engine. The development of the engine part, which is often referred to as the “heart” of the spacecraft, was led by Hanwha Aerospace using its world-class aircraft engine assembly technology.

nuri
The Composition of Korea Space Launch Vehicle-II (Nuri)
nuri
Payload Fairing
  • A nose cone for protecting the spacecraft payload
  • After separating from the spacecraft, falls to a ground location 1,508km away from the separation point
nuri
Third Stage (7-ton Liquid Fuel Engine)
  • Length: 7m / Diameter: 2.6m
  • Travels up to the altitude of the satellite orbit
nuri
Second Stage (75-ton Liquid Fuel Engine)
  • Length: 15.6m / Diameter: 2.6m
  • After separating the first stage, travels up to 240km altitude before separation and fall
nuri
First Stage (4 Clustered 75-ton Liquid Fuel Engines)
  • Length: 23m / Diameter: 3.5m
  • After the launch, travels up to 50km altitude before separation and fall


Hanwha Aerospace was not only responsible for assembling all different engine parts into a single integrated engine of Nuri, but also manufactured some key parts including the turbopump, the gimbal mount and the valves.

Other South Korean firms that participated in developing the engine were Space Solution Co., S&H Co., Vitzro Nextech, Neospec Co., Samyang Chemical and Hy-Lok Co.

Nuri was originally set to launch in February of this year but the timeline was adjusted to October after identifying an issue with the forebody, a part that connects the first and second stages of the rocket. Hankuk Fiber, a local company with expertise in developing carbon-based composite materials, came to the rescue. Nuri is now equipped with a forebody made from Hankuk Fiber’s composite materials.

The mobile launcher platform at Naro Space Center, where Nuri will launch later this month, was designed by the Hyundai Heavy Industries Group. The platform is often called the umbilical tower as it is used to inject fuel and key oxidizing agents into the spacecraft body.   

Hyundai Heavy-designed mobile launcher platform in green
Hyundai Heavy-designed mobile launcher platform in green

Korea Aerospace Industries Ltd. (KAI) played a key role in developing the propulsion tank for the first stage of the rocket, whereas Doowon Heavy Industries Co. manufactured the structures that connect the fuel tanks and oxidizer tanks. KAI was also responsible for assembling all the different components and structures of the whole spacecraft.

TECHNOLOGICAL BREAKTHROUGHS

A number of key technological advancements were made in the development of Nuri. First, the engine clustering technology was used for the first time in South Korea. The clustering of the four 75-ton fuel engines allows the spacecraft to thrust with a desired level of power without a heavier, larger engine.

Experts note that Nuri’s engine performance is on par with those of Elon Musk’s SpaceX. Their levels of fuel efficiency are similar, which can be measured by vacuum-specific impulse. Vacuum-specific impulse is simply described as the amount of thrust that the rocket body can generate when burning 1 kg of fuel in a vacuum. It is measured in seconds or the time that the body can travel per kilo of fuel.



The Korea Aerospace Research Institute (KARI) said that Nuri's first-stage launch has a vacuum specific impulse of 299.5 seconds, slightly below SpaceX’s Merlin 1C with 304 seconds or earlier versions of Merlin 1D. Merlin 1D, which was equipped on Space X’s reusable rocket Falcon 9, has a vacuum specific impulse of 311 seconds.



KARI has also put significant efforts into the tracking and aviation control of Nuri. The institute has not only set up a tracking station in Jeju Island, South Korea, but also an overseas station in the island of Palau in the Pacific Ocean.

KARI added that the Palau station is equipped with large telemetry ground antenna, 7.3m in radius, to receive remote sensing data and for satellite communications. The station can receive data and images from a projectile as far away as 3,000 km, allowing it to track Nuri’s projectiles near the equator.

Nuri will be launched together with a dummy satellite for performance verification purposes. A real working satellite will be equipped next May when KARI will launch Nuri for the second time.

“South Korea by 2022 will launch a satellite that will orbit the moon and will land a spacecraft on the moon by 2030,” said South Korean President Moon Jae-in during a technological inspection session of Nuri in March.

Aerospace experts in Korea say that while technology is an area that needs further advancement, the industry also needs political support from the government. Even if the countries like South Korea can make homegrown space launch vehicles, the US is still dominant in technologies used in satellites and space probes. According to the International Traffic in Arms Regulations (ITAR), the US only allows American spacecraft components makers to supply products globally after certain strict conditions have been met.

The experts also highlighted that America’s recent lifting of South Korea’s missile restrictions will benefit the aerospace in the country in the long run.

“The missile restriction was an obstacle to South Korea’s space industry development. Now we have more business opportunities including the use of solid fuels and boosters. The next task for the government is to lay the groundwork for moon exploration through proactive discussions with the US,” said an industry expert.

Write to Min-jun Suh, See-eun Lee and Hae-sung Lee at morandol@hankyung.com

Daniel Cho edited this article.

Comment 0

0/300