|Space Launch Report: Unha Data Sheet|
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|Unha (Taepo Dong 2)
Unha ("Galaxy"), is a three-stage North Korean rocket believed to be derived from a two-stage ballistic missile known in the West as "Taepo Dong 2". The rocket first flew, unsuccessfully, on July 5, 2006 from Musudan-ri in the northeast of the country. Taepo Dong 2, believed to have been attempting a two-stage suborbital missile test, failed after only 40 seconds. Taepo Dong 2's new first stage was powered by four main engines, one of which powered the country's earlier Taepo Dong 1 first stage, itself based on North Korea's Scud-derived Nodong missile. The four engines, when augmented by four smaller steering engines, produce about 120 tonnes of liftoff thrust, sufficient to rapidly lift the presumed 80-90+ tonne launch vehicle.
The configuration is similar in some ways to China's DF-4 two-stage missile and its follow-on CZ-1 orbital launcher, which added a small third stage to DF-4. DF-4, developed during the 1960s, used a DF-3 missile as the basis of its first stage. DF-3's first stage was slightly smaller in diameter than North Korea's Unha/Taepo Dong 2 first stage.
"Unha 2" 2009 Launch
In 2009, North Korea revealed its "Unha" launcher to the world when it attempted a satellite launch with its "Unha-2" rocket from Musudan-ri on April 5, 2009. The launch occurred at 02:30 UTC. No confirmation of the planned Kwangmyongsong-2 ("Bright Shining Star") satellite orbital insertion was subsequently reported. North American Aerospace Defense Command and U.S. Northern Command did not track any objects entering orbit, but called the "Taepo Dong 2 missile" a "space launch vehicle". For the first time, North Korea showed images of the rocket and a video of the liftoff. "Unha 2" appeared to have a small third stage added to the original "Taepo Dong 2" missile configuration.
Japanese authorities reported that the rocket's first
stage fell into the Sea of Japan and that the second stage had flown over Japan on a
due-east trajectory. Prior to the launch, North Korea announced that the first
stage would fall 500-750 km downrange and that the second stage would fall 3,150-3,950 km
downrange. South Korean officials said that the second stage had landed short
of its planned drop zone, implying a possible second stage failure. Later reports
from U.S. authorities suggested that the second stage did reach full range, implying a
separation or third stage failure.
"Unha 3" on new pad at Sohae in 2012
North Korea attempted again to orbit a satellite with Unha (identified as "Unha 3") from its new Sohae Satellite Launching Station near Tongchang-ri in the northwest corner of the country on April 12, 2012, but the launch failed. A "flare" was reportedly observed more than one minute after 22:38:55 UTC liftoff and the rocket fell into the North China Sea. Fragments fell into an area near the planned first stage drop zone, around 190-200 km west of Kunsan, South Korea, indicating that something went wrong around the time of staging between the first and second stages.
"Unha 3" was aimed toward the south in an attempt to place its 100 kg Kwangmyongsong 3 satellite into near-polar Earth orbit.
The 90 tonne three-stage rocket, similar in appearance to the "Unha 2" launched in 2009 - except with a slightly longer third stage, was exhibited by the North Koreans to international media several days before the launch, the first time outsiders have been allowed to see this long-range rocket. Media personnel were not notified of the launch before it took place and were unable to observe the failure. In a break from past launch failure denials, North Korea announced the failure in a state television broadcast several hours after the attempt.
After three known failed attempts spanning 14 years, North Korea joined the world's "space club" with a successful orbital launch from its Sohae launch site on December 12, 2012. A three-stage Unha 3 rocket carried the second Kwangmyongsong 3 ("Star of Hope") satellite into a 494 x 588 km x 97.4 deg sun synchronous orbit after a 00:51 UTC liftoff. Time from liftoff to satellite separation was 567 seconds.
The rocket flew south across the Yellow and East China Seas during its ascent before skirting the east coast of the Phillipines.
Although the launch was a success, and the satellite and upper stage were tracked in orbit, no radio transmissions from the satellite were detected by Western observers in the days following the launch.
It was the second Unha 3 launch of the year. The
first attempt failed shortly after liftoff from the same site on April 12.
North Korea's first orbital space launch attempt occurred on August 31, 1998. That failed launch was performed by a Taepo Dong 1 rocket. Taepo Dong 1 used a solid motor third stage, a Scud-missile-based second stage, and a "Rodong-1" based first stage. Rodong-1 was a North Korean-developed stage thought to be a scale-up of the old Soviet Scud missile. Taepo Dong 1 stood 22.5 meters tall, was 1.8 meters in diameter, and weighed about 21 tonnes.
Analysis of North Koreas Unha-2 Launch Vehicle, David Wright, Union of Concerned
Scientists, March 20, 2009
Last Update: January 26, 2013